feat(client): device pairing flow (v2.2.0-alpha3)

Completes PR #3 of the multi-device roadmap. Two devices of the same
identity can now be linked via a six-digit code + relay envelope
handshake. Chain-level fan-out (alpha2) and self-wipe on revoke (this
release, earlier commit) already work end-to-end.

New device — app/(auth)/pair.tsx:
  * Generates fresh X25519 keypair + six-digit code locally.
  * Displays them for transcription on the primary device.
  * Polls /relay/inbox on its own x25519 pub every 2.5s.
  * Decrypts each envelope with the session priv + sender_pub.
  * Accepts only payloads where {v=1, type=pair-handshake, code matches}.
  * On success, assembles a KeyFile (master Ed25519 from envelope,
    x25519 from session) and redirects into (app).

Primary device — app/(app)/devices.tsx:
  * "Link new device" opens a modal asking for {code, device key, name}.
  * On submit: builds+submits LINK_DEVICE tx for the new pub, then
    sends a one-shot relay envelope carrying {master_pub, master_priv,
    master_x25519_pub, code} encrypted for the new device's x25519 pub.
  * Optimistic local insert so the new row appears immediately.

Entry point — app/index.tsx:
  * Third button on welcome slide 3: "Pair". Routes to /auth/pair.
    Create / Import remain unchanged for fresh identities.

Security:
  * Master Ed25519 priv leaves the source device ONLY inside an envelope
    sealed with NaCl box for the new device's X25519 pub. The relay node
    sees only ciphertext.
  * Six-digit code (~20 bits) gates acceptance — an attacker who guesses
    both a session pub AND the code is still filtered by the X25519
    decryption itself (code match is belt-and-suspenders).
  * Envelope stays in relay mailbox until TTL — no DELETE call yet;
    idempotent on our side (saveKeyFile overwrites, session pub
    never polled after redirect).

Known trade-offs:
  * Manual transcription of a 64-char hex key is ugly. Alpha4 will
    offer a QR fallback on phones with cameras; desktop keeps typing.
  * No rate limit on the polling. Fine for a 1-minute handshake, needs
    cap-on-stale if a user leaves the screen open.

Dockerfile

@@ -1,5 +1,5 @@
 # ---- build stage ----
-FROM golang:1.24-alpine AS builder
+FROM golang:1.25-alpine AS builder
 
 WORKDIR /app
 

README.md

@@ -22,6 +22,7 @@
 ## Содержание
 
 - [Быстрый старт](#быстрый-старт)
+- [Поднятие ноды — пошагово](#поднятие-ноды--пошагово)
 - [Продакшен деплой](#продакшен-деплой)
 - [Архитектура](#архитектура)
 - [REST / WebSocket API](#rest--websocket-api)
@@ -66,6 +67,160 @@ curl -s http://localhost:8080/api/well-known-version | jq .
 
 3-node dev-кластер (для тестов PBFT кворума, slashing, federation): `docker compose up --build -d` — см. [`docs/quickstart.md`](docs/quickstart.md).
 
+## Поднятие ноды — пошагово
+
+Ниже — полный минимум для двух сценариев, которые покрывают 99% случаев:
+**первая нода сети** (genesis) и **присоединение к существующей сети**.
+Все флаги читаются также из соответствующего `DCHAIN_*` env-var (CLI > env > default).
+
+### Шаг 1. Ключи
+
+```bash
+# Ключ identity ноды (Ed25519 — подпись блоков + tx)
+./client keygen --out keys/node.json
+# relay-ключ (X25519 — E2E-mailbox) создаётся нодой сам при первом старте,
+# но можно задать путь заранее через --relay-key.
+```
+
+### Шаг 2a. Первая нода (genesis)
+
+Поднимает новую сеть с одним валидатором. `--genesis=true` **только** для самой первой ноды и **только один раз** — если блок 0 уже есть в `--db`, флаг игнорируется.
+
+```bash
+./node \
+  --genesis=true \
+  --key=keys/node.json \
+  --db=./chaindata \
+  --mailbox-db=./mailboxdata \
+  --feed-db=./feeddata \
+  --listen=/ip4/0.0.0.0/tcp/4001 \
+  --announce=/ip4/<ВАШ-ПУБЛИЧНЫЙ-IP>/tcp/4001 \
+  --stats-addr=:8080 \
+  --register-relay=true \
+  --relay-fee=1000
+```
+
+`--announce` **обязателен** для любой ноды смотрящей в интернет (VPS / внешний IP / Docker с проброшенным портом). Без него libp2p пытается UPnP/NAT-PMP и чаще всего промахивается.
+
+### Шаг 2b. Вторая и последующие ноды
+
+Нужен **один** из двух способов узнать первую ноду. Второй удобнее.
+
+**Через HTTP URL живой ноды** (рекомендуется — нода сама заберёт multiaddr через `/api/network-info`, проверит genesis_hash и синхронизирует цепь):
+
+```bash
+./node \
+  --join=https://first-node.example.com \
+  --key=keys/node.json \
+  --db=./chaindata \
+  --mailbox-db=./mailboxdata \
+  --feed-db=./feeddata \
+  --listen=/ip4/0.0.0.0/tcp/4001 \
+  --announce=/ip4/<ВАШ-ПУБЛИЧНЫЙ-IP>/tcp/4001 \
+  --stats-addr=:8080 \
+  --register-relay=true \
+  --relay-fee=1000
+```
+
+**Через libp2p multiaddr** (если есть прямой мульти-адрес):
+
+```bash
+./node \
+  --peers=/ip4/1.2.3.4/tcp/4001/p2p/12D3KooW... \
+  # остальные флаги как выше
+```
+
+**Автоприсоединение к validator set** происходит не само: после того как нода синхронизируется, действующий validator должен вызвать `client add-validator --target <your-pub> --cosigs ...` (multi-sig admit). До этого новая нода живёт как **observer** — читает и гоняет tx, но не голосует. Запустить ноду **явно** как observer (никогда не проситься в validator set): `--observer=true`.
+
+### Все флаги `node`
+
+CLI / env / default. Группы:
+
+**Storage**
+| Флаг | Env | Default | Назначение |
+|------|-----|---------|-----------|
+| `--db` | `DCHAIN_DB` | `./chaindata` | BadgerDB блокчейна |
+| `--mailbox-db` | `DCHAIN_MAILBOX_DB` | `./mailboxdata` | E2E-конверты 1:1 чатов |
+| `--feed-db` | `DCHAIN_FEED_DB` | `./feeddata` | Тела постов ленты (off-chain) |
+| `--feed-ttl-days` | `DCHAIN_FEED_TTL_DAYS` | `30` | Через сколько дней тела постов auto-evict'ятся (метаданные on-chain остаются вечно) |
+
+**Identity**
+| Флаг | Env | Default | Назначение |
+|------|-----|---------|-----------|
+| `--key` | `DCHAIN_KEY` | `./node.json` | Ed25519 ключ ноды |
+| `--relay-key` | `DCHAIN_RELAY_KEY` | `./relay.json` | X25519 ключ для relay-mailbox (создастся сам) |
+| `--wallet` | `DCHAIN_WALLET` | — | Отдельный payout-кошелёк (опционально) |
+| `--wallet-pass` | `DCHAIN_WALLET_PASS` | — | Парольная фраза для wallet-файла |
+
+**Network**
+| Флаг | Env | Default | Назначение |
+|------|-----|---------|-----------|
+| `--listen` | `DCHAIN_LISTEN` | `/ip4/0.0.0.0/tcp/4001` | libp2p listen multiaddr |
+| `--announce` | `DCHAIN_ANNOUNCE` | — | Multiaddr который нода рассказывает пирам (обязателен на VPS/внешнем IP) |
+| `--peers` | `DCHAIN_PEERS` | — | Bootstrap multiaddrs, comma-separated |
+| `--join` | `DCHAIN_JOIN` | — | HTTP URL живой ноды для авто-дискавери — получает peers и genesis_hash |
+| `--allow-genesis-mismatch` | — | `false` | Отключить защиту, падающую при расхождении локального и seed'ового genesis (только для явной миграции) |
+
+**Consensus & role**
+| Флаг | Env | Default | Назначение |
+|------|-----|---------|-----------|
+| `--genesis` | `DCHAIN_GENESIS` | `false` | Создать блок 0 (только для самой первой ноды сети) |
+| `--validators` | `DCHAIN_VALIDATORS` | — | Исходный validator set (CSV pub-keys) — применяется только при genesis |
+| `--observer` | `DCHAIN_OBSERVER` | `false` | Observer-режим: синхронизируется и отдаёт API, но не голосует и не предлагает блоки |
+| `--heartbeat` | `DCHAIN_HEARTBEAT` | `true` | Периодический HEARTBEAT-tx (нужен для liveness-детекции валидаторов) |
+
+**Relay / mailbox**
+| Флаг | Env | Default | Назначение |
+|------|-----|---------|-----------|
+| `--register-relay` | `DCHAIN_REGISTER_RELAY` | `false` | Отправить `REGISTER_RELAY` tx на старте (объявить ноду публичным relay'ем) |
+| `--relay-fee` | `DCHAIN_RELAY_FEE` | `1000` | Плата за доставку одного сообщения в µT (1000 = 0.001 T). `0` = бесплатный relay |
+
+**Media scrubber (feed)**
+| Флаг | Env | Default | Назначение |
+|------|-----|---------|-----------|
+| `--media-sidecar-url` | `DCHAIN_MEDIA_SIDECAR_URL` | — | URL FFmpeg-сайдкара для видео-скраба. Пустой = только картинки |
+| `--allow-unscrubbed-video` | `DCHAIN_ALLOW_UNSCRUBBED_VIDEO` | `false` | Принимать видео **без** серверного скраба (опасно — EXIF/GPS/автор-теги останутся) |
+
+**HTTP API**
+| Флаг | Env | Default | Назначение |
+|------|-----|---------|-----------|
+| `--stats-addr` | `DCHAIN_STATS_ADDR` | `:8080` | Адрес HTTP/WS сервера |
+| `--api-token` | `DCHAIN_API_TOKEN` | — | Bearer-токен для submit tx. Пустой = публичная нода |
+| `--api-private` | `DCHAIN_API_PRIVATE` | `false` | Требовать токен также на чтение |
+| `--disable-ui` | `DCHAIN_DISABLE_UI` | `false` | Отключить HTML-explorer (JSON API остаётся) |
+| `--disable-swagger` | `DCHAIN_DISABLE_SWAGGER` | `false` | Отключить `/swagger*` |
+
+**Resource caps** (новое в v2.1.0)
+| Флаг | Env | Default | Назначение |
+|------|-----|---------|-----------|
+| `--max-cpu` | `DCHAIN_MAX_CPU` | `0` | Сколько CPU-ядер Go-runtime'у (`GOMAXPROCS`). `0` = все |
+| `--max-ram-mb` | `DCHAIN_MAX_RAM_MB` | `0` | Soft-лимит Go-хипа в MiB (`GOMEMLIMIT`). `0` = без лимита. *Не OOM-kill'ит — усиливает GC при приближении* |
+| `--feed-disk-limit-mb` | `DCHAIN_FEED_DISK_LIMIT_MB` | `0` | Жёсткая квота на feed-БД. При превышении `/feed/publish` отвечает 507. Существующие посты продолжают отдаваться |
+| `--chain-disk-limit-mb` | `DCHAIN_CHAIN_DISK_LIMIT_MB` | `0` | Advisory-квота на блокчейн-БД. Превышение → `WARN` в лог раз в минуту (жёстко не отказываем — сломали бы консенсус) |
+
+Для реального sandboxing (hard-kill при OOM, hard CPU throttling) используйте `docker run --cpus --memory` или systemd `CPUQuota` / `MemoryMax` поверх этих флагов.
+
+**Update / versioning**
+| Флаг | Env | Default | Назначение |
+|------|-----|---------|-----------|
+| `--update-source-url` | `DCHAIN_UPDATE_SOURCE_URL` | — | Gitea `/api/v1/repos/{owner}/{repo}/releases/latest` для `/api/update-check` |
+| `--update-source-token` | `DCHAIN_UPDATE_SOURCE_TOKEN` | — | PAT для приватного репо |
+| `--log-format` | `DCHAIN_LOG_FORMAT` | `text` | `text` (human) или `json` (Loki/ELK) |
+| `--governance-contract` | `DCHAIN_GOVERNANCE_CONTRACT` | — | ID governance-контракта для динамических параметров |
+| `--version` | — | — | Печатает версию и выходит |
+
+### Минимальные чек-листы
+
+**Первая нода (открытая):** `--genesis=true` + `--key` + `--announce` на внешний IP + `--stats-addr` + опционально `--register-relay=true --relay-fee=...` чтобы сразу монетизировать relay-трафик.
+
+**Joiner:** `--join=<url-любой-живой-ноды>` + `--key` + `--announce` + `--stats-addr`. После синка попросите действующего валидатора поднять `add-validator` (иначе остаётесь observer'ом до принятия — это нормально и безопасно).
+
+**Приватная/домашняя нода** без публичного эксплорера: добавьте `--api-token=<random>`, `--api-private=true`, `--disable-ui=true`, `--disable-swagger=true`. Clients передают `Authorization: Bearer <token>`.
+
+**Слабое железо:** `--max-cpu=2 --max-ram-mb=1024 --feed-disk-limit-mb=2048 --chain-disk-limit-mb=10240`.
+
+Docker-обёртка с теми же флагами — в [`deploy/single/README.md`](deploy/single/README.md).
+
 ## Продакшен деплой
 
 Два варианта, по масштабу.

blockchain/chain.go

@@ -54,6 +54,9 @@ const (
 	prefixRelay         = "relay:"         // relay:<node_pubkey> → RegisterRelayPayload JSON
 	prefixRelayHB       = "relayhb:"       // relayhb:<node_pubkey> → unix seconds (int64) of last HB
 	prefixRelayProof    = "relayproof:"    // relayproof:<envelopeID> → claimant node_pubkey (1 claim per envelope)
+	// Multi-device registry (v2.2.0)
+	prefixDevice          = "device:"        // device:<x25519_pub> → DeviceRecord JSON
+	prefixDevicesByOwner  = "devicesbyowner:" // devicesbyowner:<master_pub>:<x25519_pub> → "" (reverse index for O(k) listing)
 	prefixContactIn     = "contact_in:"    // contact_in:<targetPub>:<requesterPub> → contactRecord JSON
 	prefixValidator     = "validator:"     // validator:<pubkey> → "" (presence = active)
 	prefixContract      = "contract:"      // contract:<contractID> → ContractRecord JSON
@@ -771,6 +774,99 @@ func PayChanCloseSigPayload(channelID string, balanceA, balanceB, nonce uint64)
 	return payChanCloseSigPayload(channelID, balanceA, balanceB, nonce)
 }
 
+// DevicesOf returns the active (non-revoked) device records for a master
+// identity. Sender fan-out reads this to decide how many envelopes to
+// produce per outgoing message. Empty slice (not error) for identities
+// with no registry entries yet — caller should fall back to the legacy
+// single-X25519 path via IdentityInfo.
+func (c *Chain) DevicesOf(masterPub string) ([]DeviceRecord, error) {
+	var out []DeviceRecord
+	err := c.db.View(func(txn *badger.Txn) error {
+		prefix := []byte(prefixDevicesByOwner + masterPub + ":")
+		it := txn.NewIterator(badger.IteratorOptions{Prefix: prefix, PrefetchValues: false})
+		defer it.Close()
+		for it.Rewind(); it.Valid(); it.Next() {
+			key := it.Item().KeyCopy(nil)
+			// key layout: devicesbyowner:<master>:<x25519> — take the suffix
+			x25519Pub := string(key[len(prefix):])
+			recItem, err := txn.Get([]byte(prefixDevice + x25519Pub))
+			if err != nil {
+				// Reverse index points to a missing record — stale entry,
+				// skip silently (shouldn't happen unless the DB was tampered
+				// with, but we don't want to fail the whole call).
+				continue
+			}
+			var rec DeviceRecord
+			if verr := recItem.Value(func(v []byte) error {
+				return json.Unmarshal(v, &rec)
+			}); verr != nil {
+				continue
+			}
+			if rec.RevokedAt != 0 {
+				continue
+			}
+			out = append(out, rec)
+		}
+		return nil
+	})
+	return out, err
+}
+
+// countActiveDevicesForOwner walks the reverse index (entries there are,
+// by construction, non-revoked — UNLINK_DEVICE deletes the index row).
+// O(k) where k = active device count, bounded by MaxDevicesPerOwner.
+func (c *Chain) countActiveDevicesForOwner(txn *badger.Txn, masterPub string) (int, error) {
+	prefix := []byte(prefixDevicesByOwner + masterPub + ":")
+	it := txn.NewIterator(badger.IteratorOptions{Prefix: prefix, PrefetchValues: false})
+	defer it.Close()
+	n := 0
+	for it.Rewind(); it.Valid(); it.Next() {
+		n++
+	}
+	return n, nil
+}
+
+// validateDevicePubKey checks the wire-level format of a device X25519
+// public key: 64 hex characters (32 bytes). Does NOT check that the key
+// is a valid curve point — senders learn that at encrypt time, and an
+// invalid point there just yields garbage ciphertext which the device
+// can't decrypt (self-punishing).
+func validateDevicePubKey(hexPub string) error {
+	if len(hexPub) != 64 {
+		return fmt.Errorf("x25519_pub_key must be 64 hex chars (got %d)", len(hexPub))
+	}
+	// Enforce strict lowercase-hex to keep keys canonical across clients —
+	// two clients hashing the same bytes with different letter cases would
+	// produce different registry lookups, which breaks sender fan-out.
+	for _, r := range hexPub {
+		switch {
+		case r >= '0' && r <= '9':
+		case r >= 'a' && r <= 'f':
+		default:
+			return fmt.Errorf("x25519_pub_key must be lowercase hex")
+		}
+	}
+	return nil
+}
+
+// validateDeviceName enforces the UX constraint that device labels stay
+// short and printable — this field gets displayed in Settings → Devices
+// and has no business carrying newlines, control chars, or 2KB blobs.
+func validateDeviceName(name string) error {
+	if name == "" {
+		return fmt.Errorf("device_name is required")
+	}
+	if len(name) > MaxDeviceNameLen {
+		return fmt.Errorf("device_name %d bytes > max %d", len(name), MaxDeviceNameLen)
+	}
+	for _, r := range name {
+		if r < 0x20 || r == 0x7f {
+			return fmt.Errorf("device_name contains a control character")
+		}
+	}
+	return nil
+}
+
 // Reputation returns the reputation stats for a public key.
 func (c *Chain) Reputation(pubKeyHex string) (RepStats, error) {
 	var r RepStats
@@ -1261,6 +1357,127 @@ func (c *Chain) applyTx(txn *badger.Txn, tx *Transaction) (uint64, error) {
 			return 0, err
 		}
 
+	case EventLinkDevice:
+		// Master Ed25519 (= tx.From) publishes a per-device X25519 pub.
+		// Validation:
+		//   1. Payload well-formed, X25519 pub is hex(32 bytes).
+		//   2. Device name is short + printable.
+		//   3. X25519 pub isn't already registered to a DIFFERENT owner.
+		//   4. Same owner re-linking the same pub is a no-op refresh
+		//      (updates device_name / added_at — useful for rename).
+		//   5. Owner has < MaxDevicesPerOwner active (non-revoked) devices.
+		//
+		// Fee: standard tx.Fee is debited from master's balance — cheap
+		// anti-spam. Block validation already enforced `tx.Fee >= MinFee`.
+		if err := c.debitBalance(txn, tx.From, tx.Fee); err != nil {
+			return 0, fmt.Errorf("LINK_DEVICE debit: %w", err)
+		}
+		var p LinkDevicePayload
+		if err := json.Unmarshal(tx.Payload, &p); err != nil {
+			return 0, fmt.Errorf("%w: LINK_DEVICE bad payload: %v", ErrTxFailed, err)
+		}
+		if err := validateDevicePubKey(p.X25519PubKey); err != nil {
+			return 0, fmt.Errorf("%w: LINK_DEVICE: %v", ErrTxFailed, err)
+		}
+		if err := validateDeviceName(p.DeviceName); err != nil {
+			return 0, fmt.Errorf("%w: LINK_DEVICE: %v", ErrTxFailed, err)
+		}
+		devKey := []byte(prefixDevice + p.X25519PubKey)
+		if item, err := txn.Get(devKey); err == nil {
+			var existing DeviceRecord
+			if verr := item.Value(func(v []byte) error {
+				return json.Unmarshal(v, &existing)
+			}); verr == nil {
+				if existing.Owner != tx.From {
+					return 0, fmt.Errorf("%w: LINK_DEVICE: x25519 pub already linked to a different owner",
+						ErrTxFailed)
+				}
+				// Same owner — rename/refresh path. Keep AddedAt.
+				existing.DeviceName = p.DeviceName
+				existing.RevokedAt = 0 // re-link cancels a previous revoke
+				refreshed, _ := json.Marshal(existing)
+				if err := txn.Set(devKey, refreshed); err != nil {
+					return 0, err
+				}
+				// Restore reverse index too — UNLINK_DEVICE deletes it, so
+				// a re-link after revoke must recreate it or DevicesOf
+				// will skip the record.
+				idxKey := []byte(prefixDevicesByOwner + tx.From + ":" + p.X25519PubKey)
+				if err := txn.Set(idxKey, []byte{}); err != nil {
+					return 0, err
+				}
+				break
+			}
+		}
+		// Count owner's active devices.
+		active, err := c.countActiveDevicesForOwner(txn, tx.From)
+		if err != nil {
+			return 0, fmt.Errorf("LINK_DEVICE count devices: %w", err)
+		}
+		if active >= MaxDevicesPerOwner {
+			return 0, fmt.Errorf("%w: LINK_DEVICE: owner already has %d devices (max %d)",
+				ErrTxFailed, active, MaxDevicesPerOwner)
+		}
+		rec := DeviceRecord{
+			Owner:        tx.From,
+			X25519PubKey: p.X25519PubKey,
+			DeviceName:   p.DeviceName,
+			AddedAt:      tx.Timestamp.Unix(),
+		}
+		val, _ := json.Marshal(rec)
+		if err := txn.Set(devKey, val); err != nil {
+			return 0, err
+		}
+		idxKey := []byte(prefixDevicesByOwner + tx.From + ":" + p.X25519PubKey)
+		if err := txn.Set(idxKey, []byte{}); err != nil {
+			return 0, err
+		}
+
+	case EventUnlinkDevice:
+		// Revoke (soft-delete) a device record. Mark RevokedAt and keep
+		// the row — clients wake up, notice their own pub is revoked, and
+		// wipe local state. A permanent delete would let a sender that
+		// missed the revoke keep encrypting for the old pub silently.
+		if err := c.debitBalance(txn, tx.From, tx.Fee); err != nil {
+			return 0, fmt.Errorf("UNLINK_DEVICE debit: %w", err)
+		}
+		var p UnlinkDevicePayload
+		if err := json.Unmarshal(tx.Payload, &p); err != nil {
+			return 0, fmt.Errorf("%w: UNLINK_DEVICE bad payload: %v", ErrTxFailed, err)
+		}
+		if err := validateDevicePubKey(p.X25519PubKey); err != nil {
+			return 0, fmt.Errorf("%w: UNLINK_DEVICE: %v", ErrTxFailed, err)
+		}
+		devKey := []byte(prefixDevice + p.X25519PubKey)
+		item, err := txn.Get(devKey)
+		if err != nil {
+			return 0, fmt.Errorf("%w: UNLINK_DEVICE: device not found", ErrTxFailed)
+		}
+		var existing DeviceRecord
+		if verr := item.Value(func(v []byte) error {
+			return json.Unmarshal(v, &existing)
+		}); verr != nil {
+			return 0, fmt.Errorf("UNLINK_DEVICE decode: %w", verr)
+		}
+		if existing.Owner != tx.From {
+			return 0, fmt.Errorf("%w: UNLINK_DEVICE: signer is not the owner of this device",
+				ErrTxFailed)
+		}
+		if existing.RevokedAt != 0 {
+			// Already revoked — idempotent success, don't error.
+			break
+		}
+		existing.RevokedAt = tx.Timestamp.Unix()
+		updated, _ := json.Marshal(existing)
+		if err := txn.Set(devKey, updated); err != nil {
+			return 0, err
+		}
+		// Drop reverse index so countActiveDevicesForOwner is O(k_active).
+		idxKey := []byte(prefixDevicesByOwner + tx.From + ":" + p.X25519PubKey)
+		if err := txn.Delete(idxKey); err != nil {
+			return 0, err
+		}
+
 	case EventContactRequest:
 		var p ContactRequestPayload
 		if err := json.Unmarshal(tx.Payload, &p); err != nil {

blockchain/devices_test.go

@@ -0,0 +1,413 @@
+package blockchain_test
+
+// Multi-device registry tests (v2.2.0). Cover happy-path link + list,
+// unlink idempotency, ownership validation, max-devices guard, and
+// backward-compat sender fall-back semantics (empty list for unknown
+// master). HTTP-layer tests live in the node package; these stay at
+// chain level — applyTx + state-shape only.
+
+import (
+	"crypto/rand"
+	"encoding/hex"
+	"strings"
+	"sync/atomic"
+	"testing"
+	"time"
+
+	"go-blockchain/blockchain"
+	"go-blockchain/identity"
+)
+
+// uniqueTxID sidesteps the `chain_test.go:txID` race where two helper
+// calls in the same nanosecond produce identical tx IDs → chain.AddBlock
+// dedupes the second as "already committed". We add a strictly-monotonic
+// counter so every tx built in the same test gets a fresh ID even on
+// fast machines.
+var devicesTxIDCounter atomic.Uint64
+
+func uniqueTxID() string {
+	n := devicesTxIDCounter.Add(1)
+	h := make([]byte, 16)
+	_, _ = rand.Read(h)
+	return hex.EncodeToString(h) + ":" + time.Now().Format("150405.000000000") + ":" + itoa(n)
+}
+
+func itoa(n uint64) string {
+	// tiny local conversion to avoid importing strconv just for tests.
+	if n == 0 {
+		return "0"
+	}
+	var buf [20]byte
+	i := len(buf)
+	for n > 0 {
+		i--
+		buf[i] = byte('0' + n%10)
+		n /= 10
+	}
+	return string(buf[i:])
+}
+
+// linkDeviceRawTx / unlinkDeviceRawTx build txs with guaranteed-unique
+// IDs so we can stuff many of them into a single block during tests.
+func linkDeviceRawTx(master *identity.Identity, x25519Pub, name string) *blockchain.Transaction {
+	payload := mustJSON(blockchain.LinkDevicePayload{
+		X25519PubKey: x25519Pub,
+		DeviceName:   name,
+	})
+	return &blockchain.Transaction{
+		ID:        uniqueTxID(),
+		Type:      blockchain.EventLinkDevice,
+		From:      master.PubKeyHex(),
+		Fee:       blockchain.MinFee,
+		Payload:   payload,
+		Timestamp: time.Now().UTC(),
+	}
+}
+
+func unlinkDeviceRawTx(master *identity.Identity, x25519Pub string) *blockchain.Transaction {
+	payload := mustJSON(blockchain.UnlinkDevicePayload{X25519PubKey: x25519Pub})
+	return &blockchain.Transaction{
+		ID:        uniqueTxID(),
+		Type:      blockchain.EventUnlinkDevice,
+		From:      master.PubKeyHex(),
+		Fee:       blockchain.MinFee,
+		Payload:   payload,
+		Timestamp: time.Now().UTC(),
+	}
+}
+
+// randX25519Pub returns a throw-away 32-byte hex string suitable for the
+// x25519_pub_key field. We don't need the matching private key — the
+// chain only stores the pub and doesn't verify it's a valid curve point.
+func randX25519Pub(t *testing.T) string {
+	t.Helper()
+	var b [32]byte
+	if _, err := rand.Read(b[:]); err != nil {
+		t.Fatalf("rand: %v", err)
+	}
+	return hex.EncodeToString(b[:])
+}
+
+// fundIdentity credits enough balance to cover `nFees` worth of MinFee
+// payments. Every test needs this because LINK_DEVICE and UNLINK_DEVICE
+// debit tx.Fee from the master's balance — without funding the first tx
+// errors with "insufficient funds" and no state changes.
+func fundIdentity(t *testing.T, c *blockchain.Chain, val, recipient *identity.Identity, nFees int) {
+	t.Helper()
+	amount := uint64(nFees+2) * blockchain.MinFee
+	tx := makeTx(blockchain.EventTransfer, val.PubKeyHex(), recipient.PubKeyHex(),
+		amount, blockchain.MinFee, mustJSON(blockchain.TransferPayload{}))
+	mustAddBlock(t, c, buildBlock(t, c.Tip(), val, []*blockchain.Transaction{tx}))
+}
+
+// TestLinkDeviceHappyPath: after a single LINK_DEVICE, DevicesOf returns
+// exactly one record with the right owner/name/pub.
+func TestLinkDeviceHappyPath(t *testing.T) {
+	c := newChain(t)
+	val := newIdentity(t)
+	addGenesis(t, c, val)
+
+	alice := newIdentity(t)
+	fundIdentity(t, c, val, alice, 1)
+	dev1 := randX25519Pub(t)
+	tx := linkDeviceRawTx(alice, dev1, "Alice's iPhone")
+	b := buildBlock(t, c.Tip(), val, []*blockchain.Transaction{tx})
+	mustAddBlock(t, c, b)
+
+	devs, err := c.DevicesOf(alice.PubKeyHex())
+	if err != nil {
+		t.Fatalf("DevicesOf: %v", err)
+	}
+	if len(devs) != 1 {
+		t.Fatalf("expected 1 device, got %d", len(devs))
+	}
+	got := devs[0]
+	if got.Owner != alice.PubKeyHex() {
+		t.Errorf("owner: got %s, want %s", got.Owner, alice.PubKeyHex())
+	}
+	if got.X25519PubKey != dev1 {
+		t.Errorf("x25519: got %s, want %s", got.X25519PubKey, dev1)
+	}
+	if got.DeviceName != "Alice's iPhone" {
+		t.Errorf("name: got %q, want %q", got.DeviceName, "Alice's iPhone")
+	}
+	if got.RevokedAt != 0 {
+		t.Errorf("freshly linked device should have RevokedAt=0, got %d", got.RevokedAt)
+	}
+}
+
+// TestLinkDeviceMultiple: multiple devices for the same owner all show up
+// in DevicesOf, and the count matches.
+func TestLinkDeviceMultiple(t *testing.T) {
+	c := newChain(t)
+	val := newIdentity(t)
+	addGenesis(t, c, val)
+
+	alice := newIdentity(t)
+	fundIdentity(t, c, val, alice, 3)
+	pubs := []string{randX25519Pub(t), randX25519Pub(t), randX25519Pub(t)}
+	var txs []*blockchain.Transaction
+	for i, p := range pubs {
+		txs = append(txs, linkDeviceRawTx(alice, p, "device-"+string(rune('A'+i))))
+	}
+	mustAddBlock(t, c, buildBlock(t, c.Tip(), val, txs))
+
+	devs, err := c.DevicesOf(alice.PubKeyHex())
+	if err != nil {
+		t.Fatalf("DevicesOf: %v", err)
+	}
+	if len(devs) != 3 {
+		t.Fatalf("expected 3 devices, got %d", len(devs))
+	}
+}
+
+// TestLinkDeviceRejectsForeignOwner: if Alice already linked a X25519 pub
+// and Bob tries to link the SAME pub to himself, the tx is rejected.
+// This protects against a malicious actor hijacking someone else's
+// device-pub and trying to claim it.
+func TestLinkDeviceRejectsForeignOwner(t *testing.T) {
+	c := newChain(t)
+	val := newIdentity(t)
+	addGenesis(t, c, val)
+
+	alice := newIdentity(t)
+	bob := newIdentity(t)
+	fundIdentity(t, c, val, alice, 1)
+	fundIdentity(t, c, val, bob, 1)
+	dev := randX25519Pub(t)
+
+	mustAddBlock(t, c, buildBlock(t, c.Tip(), val,
+		[]*blockchain.Transaction{linkDeviceRawTx(alice, dev, "alice phone")}))
+
+	// Bob tries to claim the same pub. The chain silently drops invalid
+	// txs (they're non-fatal for block commit), so we verify the *state*:
+	// Alice still owns the pub, Bob has zero devices.
+	bobTx := linkDeviceRawTx(bob, dev, "bob phone")
+	mustAddBlock(t, c, buildBlock(t, c.Tip(), val, []*blockchain.Transaction{bobTx}))
+
+	aliceDevs, _ := c.DevicesOf(alice.PubKeyHex())
+	if len(aliceDevs) != 1 || aliceDevs[0].DeviceName != "alice phone" {
+		t.Fatalf("Alice should still own the device, got %+v", aliceDevs)
+	}
+	bobDevs, _ := c.DevicesOf(bob.PubKeyHex())
+	if len(bobDevs) != 0 {
+		t.Fatalf("Bob's hijack should have been rejected, got %+v", bobDevs)
+	}
+}
+
+// TestLinkDeviceSameOwnerRefresh: the same owner re-linking the same
+// x25519_pub is a rename/refresh (not an error), and the revoked flag
+// gets cleared if it was set.
+func TestLinkDeviceSameOwnerRefresh(t *testing.T) {
+	c := newChain(t)
+	val := newIdentity(t)
+	addGenesis(t, c, val)
+
+	alice := newIdentity(t)
+	fundIdentity(t, c, val, alice, 3)
+	dev := randX25519Pub(t)
+	mustAddBlock(t, c, buildBlock(t, c.Tip(), val,
+		[]*blockchain.Transaction{linkDeviceRawTx(alice, dev, "old name")}))
+
+	// Unlink then re-link — should restore the record.
+	mustAddBlock(t, c, buildBlock(t, c.Tip(), val,
+		[]*blockchain.Transaction{unlinkDeviceRawTx(alice, dev)}))
+	mustAddBlock(t, c, buildBlock(t, c.Tip(), val,
+		[]*blockchain.Transaction{linkDeviceRawTx(alice, dev, "new name")}))
+
+	devs, err := c.DevicesOf(alice.PubKeyHex())
+	if err != nil {
+		t.Fatalf("DevicesOf: %v", err)
+	}
+	if len(devs) != 1 {
+		t.Fatalf("expected 1 active device after re-link, got %d", len(devs))
+	}
+	if devs[0].DeviceName != "new name" {
+		t.Errorf("expected refreshed name 'new name', got %q", devs[0].DeviceName)
+	}
+}
+
+// TestUnlinkDeviceRemovesFromActive: after UNLINK_DEVICE, DevicesOf no
+// longer returns that record — senders stop fanning out to it.
+func TestUnlinkDeviceRemovesFromActive(t *testing.T) {
+	c := newChain(t)
+	val := newIdentity(t)
+	addGenesis(t, c, val)
+
+	alice := newIdentity(t)
+	fundIdentity(t, c, val, alice, 3)
+	keep := randX25519Pub(t)
+	revoke := randX25519Pub(t)
+	mustAddBlock(t, c, buildBlock(t, c.Tip(), val, []*blockchain.Transaction{
+		linkDeviceRawTx(alice, keep, "kept"),
+		linkDeviceRawTx(alice, revoke, "revoked"),
+	}))
+	mustAddBlock(t, c, buildBlock(t, c.Tip(), val,
+		[]*blockchain.Transaction{unlinkDeviceRawTx(alice, revoke)}))
+
+	devs, err := c.DevicesOf(alice.PubKeyHex())
+	if err != nil {
+		t.Fatalf("DevicesOf: %v", err)
+	}
+	if len(devs) != 1 || devs[0].X25519PubKey != keep {
+		t.Fatalf("expected only the kept device, got %+v", devs)
+	}
+}
+
+// TestUnlinkDeviceRejectsForeignSigner: Bob can't unlink Alice's device
+// even if he knows the X25519 pub — only the owner's signature (= tx.From)
+// authorises revoke.
+func TestUnlinkDeviceRejectsForeignSigner(t *testing.T) {
+	c := newChain(t)
+	val := newIdentity(t)
+	addGenesis(t, c, val)
+
+	alice := newIdentity(t)
+	bob := newIdentity(t)
+	fundIdentity(t, c, val, alice, 1)
+	fundIdentity(t, c, val, bob, 1)
+	dev := randX25519Pub(t)
+	mustAddBlock(t, c, buildBlock(t, c.Tip(), val,
+		[]*blockchain.Transaction{linkDeviceRawTx(alice, dev, "alice phone")}))
+
+	// Bob tries to unlink Alice's device — tx is silently dropped, Alice
+	// still has it in her active list.
+	mustAddBlock(t, c, buildBlock(t, c.Tip(), val,
+		[]*blockchain.Transaction{unlinkDeviceRawTx(bob, dev)}))
+
+	aliceDevs, _ := c.DevicesOf(alice.PubKeyHex())
+	if len(aliceDevs) != 1 || aliceDevs[0].X25519PubKey != dev {
+		t.Fatalf("Alice's device should still be active, got %+v", aliceDevs)
+	}
+}
+
+// TestUnlinkDeviceIdempotent: unlinking a device that's already revoked
+// does NOT error — this is needed for recovery scenarios where a client
+// retries the tx after a spotty connection.
+func TestUnlinkDeviceIdempotent(t *testing.T) {
+	c := newChain(t)
+	val := newIdentity(t)
+	addGenesis(t, c, val)
+
+	alice := newIdentity(t)
+	fundIdentity(t, c, val, alice, 3)
+	dev := randX25519Pub(t)
+	mustAddBlock(t, c, buildBlock(t, c.Tip(), val,
+		[]*blockchain.Transaction{linkDeviceRawTx(alice, dev, "phone")}))
+	mustAddBlock(t, c, buildBlock(t, c.Tip(), val,
+		[]*blockchain.Transaction{unlinkDeviceRawTx(alice, dev)}))
+	// Second unlink of the same device must apply cleanly.
+	mustAddBlock(t, c, buildBlock(t, c.Tip(), val,
+		[]*blockchain.Transaction{unlinkDeviceRawTx(alice, dev)}))
+}
+
+// TestLinkDeviceRejectsMalformedPub: payload.X25519PubKey must be 64-char
+// lowercase hex. Garbage / short / uppercase values are rejected at
+// applyTx time before any state change.
+func TestLinkDeviceRejectsMalformedPub(t *testing.T) {
+	c := newChain(t)
+	val := newIdentity(t)
+	addGenesis(t, c, val)
+
+	alice := newIdentity(t)
+	fundIdentity(t, c, val, alice, 5)
+
+	bad := []string{
+		"",                      // empty
+		"abc",                   // too short
+		strings.Repeat("x", 64), // non-hex
+		strings.Repeat("A", 64), // uppercase
+	}
+	for _, p := range bad {
+		tx := linkDeviceRawTx(alice, p, "dev")
+		mustAddBlock(t, c, buildBlock(t, c.Tip(), val, []*blockchain.Transaction{tx}))
+	}
+
+	devs, _ := c.DevicesOf(alice.PubKeyHex())
+	if len(devs) != 0 {
+		t.Fatalf("expected 0 devices after %d malformed link attempts, got %d",
+			len(bad), len(devs))
+	}
+}
+
+// TestLinkDeviceRejectsBadDeviceName: empty, too long, or control-char
+// names are refused — this field is rendered verbatim in clients.
+func TestLinkDeviceRejectsBadDeviceName(t *testing.T) {
+	c := newChain(t)
+	val := newIdentity(t)
+	addGenesis(t, c, val)
+
+	alice := newIdentity(t)
+	fundIdentity(t, c, val, alice, 5)
+	cases := map[string]string{
+		"empty":        "",
+		"too long":     strings.Repeat("a", blockchain.MaxDeviceNameLen+1),
+		"control char": "device\x01name",
+	}
+	for name, devName := range cases {
+		t.Run(name, func(t *testing.T) {
+			before, _ := c.DevicesOf(alice.PubKeyHex())
+			tx := linkDeviceRawTx(alice, randX25519Pub(t), devName)
+			mustAddBlock(t, c, buildBlock(t, c.Tip(), val, []*blockchain.Transaction{tx}))
+			after, _ := c.DevicesOf(alice.PubKeyHex())
+			if len(after) != len(before) {
+				t.Fatalf("bad %s name should not have been linked (before=%d, after=%d)",
+					name, len(before), len(after))
+			}
+		})
+	}
+}
+
+// TestLinkDeviceMaxDevices: after MaxDevicesPerOwner active devices, any
+// further LINK_DEVICE is rejected. Revoking one frees a slot.
+func TestLinkDeviceMaxDevices(t *testing.T) {
+	c := newChain(t)
+	val := newIdentity(t)
+	addGenesis(t, c, val)
+
+	alice := newIdentity(t)
+	// Enough for cap + one overflow attempt + one unlink + one replacement.
+	fundIdentity(t, c, val, alice, blockchain.MaxDevicesPerOwner+4)
+
+	// Fill to the cap — each in its own block so timestamps differ.
+	pubs := make([]string, blockchain.MaxDevicesPerOwner)
+	for i := 0; i < blockchain.MaxDevicesPerOwner; i++ {
+		pubs[i] = randX25519Pub(t)
+		mustAddBlock(t, c, buildBlock(t, c.Tip(), val,
+			[]*blockchain.Transaction{linkDeviceRawTx(alice, pubs[i], "d")}))
+	}
+	// One more — the tx is dropped, cap stays exact.
+	over := linkDeviceRawTx(alice, randX25519Pub(t), "overflow")
+	mustAddBlock(t, c, buildBlock(t, c.Tip(), val, []*blockchain.Transaction{over}))
+	if devs, _ := c.DevicesOf(alice.PubKeyHex()); len(devs) != blockchain.MaxDevicesPerOwner {
+		t.Fatalf("overflow link should have been rejected, count=%d", len(devs))
+	}
+
+	// Revoke one, then a fresh link succeeds.
+	mustAddBlock(t, c, buildBlock(t, c.Tip(), val,
+		[]*blockchain.Transaction{unlinkDeviceRawTx(alice, pubs[0])}))
+	mustAddBlock(t, c, buildBlock(t, c.Tip(), val,
+		[]*blockchain.Transaction{linkDeviceRawTx(alice, randX25519Pub(t), "replacement")}))
+	if devs, _ := c.DevicesOf(alice.PubKeyHex()); len(devs) != blockchain.MaxDevicesPerOwner {
+		t.Fatalf("after unlink+relink, should be %d active, got %d",
+			blockchain.MaxDevicesPerOwner, len(devs))
+	}
+}
+
+// TestDevicesOfEmptyForUnknown: unknown master pubs return an empty list
+// (not an error) — this preserves the sender's ability to fall back to
+// IdentityInfo.X25519Pub for legacy identities.
+func TestDevicesOfEmptyForUnknown(t *testing.T) {
+	c := newChain(t)
+	val := newIdentity(t)
+	addGenesis(t, c, val)
+
+	alice := newIdentity(t)
+	devs, err := c.DevicesOf(alice.PubKeyHex())
+	if err != nil {
+		t.Fatalf("DevicesOf: %v", err)
+	}
+	if len(devs) != 0 {
+		t.Fatalf("expected 0 devices for unknown master, got %d", len(devs))
+	}
+}

blockchain/types.go

@@ -46,6 +46,14 @@ const (
 	EventUnfollow        EventType = "UNFOLLOW"          // unfollow an author
 	EventLikePost        EventType = "LIKE_POST"         // like a post
 	EventUnlikePost      EventType = "UNLIKE_POST"       // remove a previous like
+
+	// Multi-device support (v2.2.0): each physical device of an identity gets
+	// its own X25519 keypair for the messenger mailbox. LINK/UNLINK_DEVICE
+	// publish/revoke those pubs on-chain so senders can fan-out envelopes
+	// across the recipient's active devices. Signed by the identity's
+	// master Ed25519 key.
+	EventLinkDevice   EventType = "LINK_DEVICE"
+	EventUnlinkDevice EventType = "UNLINK_DEVICE"
 )
 
 // Token amounts are stored in micro-tokens (µT).
@@ -555,6 +563,70 @@ type IdentityInfo struct {
 	X25519Pub  string `json:"x25519_pub"`  // hex Curve25519 key; empty if not published
 	Nickname   string `json:"nickname"`
 	Registered bool   `json:"registered"`   // true if REGISTER_KEY tx was committed
+	// DeviceCount is the number of currently-linked (non-revoked) devices in
+	// this identity's multi-device registry. `0` for legacy identities that
+	// only published a single X25519 via REGISTER_KEY — senders fall back
+	// to IdentityInfo.X25519Pub in that case.
+	DeviceCount int `json:"device_count"`
+}
+
+// ── Multi-device registry (v2.2.0) ───────────────────────────────────────
+
+// MaxDevicesPerOwner caps how many devices a single identity can have
+// linked concurrently. A sender must encrypt + relay one envelope per
+// device, so the multiplier bounds the per-message cost. Ten covers
+// typical users (phone + tablet + laptop + desktop + work phone + …)
+// without letting an abuse case blow up mailbox traffic. Revoked devices
+// don't count.
+const MaxDevicesPerOwner = 10
+
+// MaxDeviceNameLen caps the length of a human-friendly device label
+// ("Alice's iPhone 14", "Work MacBook Pro"). Longer names get rejected
+// at validation. Kept short to discourage using this field as a free-form
+// comment/profile channel.
+const MaxDeviceNameLen = 64
+
+// LinkDevicePayload is embedded in EventLinkDevice transactions. Master
+// Ed25519 (= tx.From) asserts that the given X25519 pub belongs to one
+// of its physical devices, publishing it so senders can fan out envelopes.
+type LinkDevicePayload struct {
+	// X25519PubKey is the hex-encoded Curve25519 pub the device generated
+	// locally. Must be unique in the device registry — senders index
+	// envelopes by this key in the relay mailbox.
+	X25519PubKey string `json:"x25519_pub_key"`
+	// DeviceName is a short human label shown in Settings → Devices.
+	// Purely informational; not used for routing.
+	DeviceName string `json:"device_name"`
+}
+
+// UnlinkDevicePayload is embedded in EventUnlinkDevice transactions. Signed
+// by master Ed25519; marks the referenced device as revoked so senders
+// stop shipping envelopes to its X25519 pub. The revoked device itself,
+// once it sees its pub in the revoked list, is expected to wipe its
+// local state (master Ed25519 priv + chat cache).
+type UnlinkDevicePayload struct {
+	X25519PubKey string `json:"x25519_pub_key"`
+}
+
+// DeviceRecord is the on-chain persisted state for one device link.
+// Stored at key `prefixDevice + x25519_pub`; the reverse index
+// `prefixDevicesByOwner + master_pub` keeps a slice of x25519 pubs per
+// owner for efficient listing.
+type DeviceRecord struct {
+	Owner        string `json:"owner"`          // master Ed25519 pub hex
+	X25519PubKey string `json:"x25519_pub_key"` // device X25519 pub hex
+	DeviceName   string `json:"device_name"`
+	AddedAt      int64  `json:"added_at"`           // unix seconds, from tx timestamp
+	RevokedAt    int64  `json:"revoked_at,omitempty"` // 0 = active; >0 = revoked
+}
+
+// DeviceInfo is the public view of a DeviceRecord served by
+// GET /api/devices/{master_pub}. Revoked records are not included
+// in the response (intentionally — sender only needs the active set).
+type DeviceInfo struct {
+	X25519PubKey string `json:"x25519_pub_key"`
+	DeviceName   string `json:"device_name"`
+	AddedAt      int64  `json:"added_at"`
 }
 
 // ConsensusMessage types used by the PBFT engine over the P2P layer.

client-app/app.json

@@ -12,12 +12,14 @@
       "infoPlist": {
         "NSMicrophoneUsageDescription": "Allow DChain to record voice messages and video.",
         "NSCameraUsageDescription": "Allow DChain to record video messages and scan QR codes.",
-        "NSPhotoLibraryUsageDescription": "Allow DChain to attach photos and videos from your library."
+        "NSPhotoLibraryUsageDescription": "Allow DChain to attach photos and videos from your library.",
+        "ITSAppUsesNonExemptEncryption": false
       }
     },
     "android": {
       "package": "com.dchain.messenger",
       "softwareKeyboardLayoutMode": "pan",
+      "usesCleartextTraffic": true,
       "permissions": [
         "android.permission.RECORD_AUDIO",
         "android.permission.CAMERA",

client-app/app/(app)/_layout.tsx

@@ -13,7 +13,7 @@
  * один раз; переходы между tab'ами их не перезапускают.
  */
 import React, { useEffect } from 'react';
-import { View } from 'react-native';
+import { View, Platform } from 'react-native';
 import { router, usePathname } from 'expo-router';
 import { useSafeAreaInsets } from 'react-native-safe-area-context';
 import { useStore } from '@/lib/store';
@@ -23,9 +23,15 @@ import { useWellKnownContracts } from '@/hooks/useWellKnownContracts';
 import { useNotifications } from '@/hooks/useNotifications';
 import { useGlobalInbox } from '@/hooks/useGlobalInbox';
 import { getWSClient } from '@/lib/ws';
-import { useDevSeed } from '@/lib/devSeed';
 import { NavBar } from '@/components/NavBar';
 import { AnimatedSlot } from '@/components/AnimatedSlot';
+import {
+  saveContact,
+  isDeviceRegistered, markDeviceRegistered, wipeAllLocalState,
+} from '@/lib/storage';
+import {
+  fetchDevices, buildLinkDeviceTx, submitTx,
+} from '@/lib/api';
 
 export default function AppLayout() {
   const keyFile  = useStore(s => s.keyFile);
@@ -37,24 +43,115 @@ export default function AppLayout() {
   //  - chat detail
   //  - compose (new post modal)
   //  - feed sub-routes (post detail, hashtag search)
+  //  - tx detail
   const hideNav =
     /^\/chats\/[^/]+/.test(pathname) ||
     pathname === '/compose' ||
-    /^\/feed\/.+/.test(pathname);
+    /^\/feed\/.+/.test(pathname) ||
+    /^\/tx\/.+/.test(pathname);
 
   useBalance();
   useContacts();
   useWellKnownContracts();
-  useDevSeed();
   useNotifications();   // permission + tap-handler
   useGlobalInbox();     // global inbox listener → notifications on new peer msg
 
+  // Ensure the Saved Messages (self-chat) contact exists as soon as the user
+  // is signed in, so it shows up in the chat list without any prior action.
+  const contacts      = useStore(s => s.contacts);
+  const upsertContact = useStore(s => s.upsertContact);
+  useEffect(() => {
+    if (!keyFile) return;
+    if (contacts.some(c => c.address === keyFile.pub_key)) return;
+    const saved = {
+      address:   keyFile.pub_key,
+      x25519Pub: keyFile.x25519_pub,
+      alias:     'Saved Messages',
+      addedAt:   Date.now(),
+    };
+    upsertContact(saved);
+    saveContact(saved).catch(() => { /* best-effort — re-added next boot anyway */ });
+  }, [keyFile, contacts, upsertContact]);
+
   useEffect(() => {
     const ws = getWSClient();
     if (keyFile) ws.setAuthCreds({ pubKey: keyFile.pub_key, privKey: keyFile.priv_key });
     else ws.setAuthCreds(null);
   }, [keyFile]);
 
+  // Multi-device registry bootstrap + revoke-detection (v2.2.0).
+  //
+  // Three branches, by (chain list × local "was registered" flag):
+  //
+  //   1. Our pub is in the chain's active list →
+  //      mark us registered locally (idempotent), done.
+  //
+  //   2. Our pub is NOT in the active list, AND we've registered before →
+  //      another device issued UNLINK_DEVICE against us. Wipe ALL local
+  //      state (master priv, contacts, chats, marker) and redirect to
+  //      the auth screen. This is the security-critical path: without
+  //      the wipe, a stolen phone after revoke would still decrypt
+  //      historical messages.
+  //
+  //   3. Our pub is NOT in the active list, AND we've NEVER registered →
+  //      first boot on this chain; submit LINK_DEVICE so senders can
+  //      target us. Failures (fee, offline) are swallowed; next launch
+  //      retries.
+  useEffect(() => {
+    if (!keyFile) return;
+    let cancelled = false;
+    (async () => {
+      let chainList;
+      try {
+        chainList = await fetchDevices(keyFile.pub_key);
+      } catch {
+        // Network unavailable — leave state unchanged; we'll resync on
+        // the next launch. Do NOT wipe on network error.
+        return;
+      }
+      if (cancelled) return;
+
+      const inActive = chainList.some(d => d.x25519_pub_key === keyFile.x25519_pub);
+      const previouslyRegistered = await isDeviceRegistered();
+      if (cancelled) return;
+
+      if (inActive) {
+        // Branch #1 — ensure the local marker is set.
+        if (!previouslyRegistered) await markDeviceRegistered();
+        return;
+      }
+
+      if (previouslyRegistered) {
+        // Branch #2 — REVOKED. Self-wipe.
+        await wipeAllLocalState();
+        useStore.getState().setKeyFile(null);
+        // The redirect-on-null-keyFile effect below will push the user
+        // back to the welcome screen automatically.
+        return;
+      }
+
+      // Branch #3 — first-boot link. Best-effort.
+      try {
+        const deviceName = Platform.select({
+          ios:     'iPhone',
+          android: 'Android phone',
+          default: 'Device',
+        }) ?? 'Device';
+        const tx = buildLinkDeviceTx({
+          from:       keyFile.pub_key,
+          x25519Pub:  keyFile.x25519_pub,
+          deviceName,
+          privKey:    keyFile.priv_key,
+        });
+        await submitTx(tx);
+        await markDeviceRegistered();
+      } catch {
+        /* next launch retries */
+      }
+    })();
+    return () => { cancelled = true; };
+  }, [keyFile]);
+
   useEffect(() => {
     if (keyFile === null) {
       const t = setTimeout(() => {

client-app/app/(app)/chats/[id].tsx

@@ -23,10 +23,10 @@ import * as Clipboard from 'expo-clipboard';
 import { useStore } from '@/lib/store';
 import { useMessages } from '@/hooks/useMessages';
 import { encryptMessage } from '@/lib/crypto';
-import { sendEnvelope } from '@/lib/api';
+import { sendEnvelope, resolveRecipientKeys } from '@/lib/api';
 import { getWSClient } from '@/lib/ws';
 import { appendMessage, loadMessages } from '@/lib/storage';
-import { randomId } from '@/lib/utils';
+import { randomId, safeBack } from '@/lib/utils';
 import type { Message } from '@/lib/types';
 
 import { Avatar }        from '@/components/Avatar';
@@ -63,6 +63,24 @@ export default function ChatScreen() {
     clearContactNotifications(contactAddress);
   }, [contactAddress, clearUnread]);
 
+  const upsertContact = useStore(s => s.upsertContact);
+  const isSavedMessages = !!keyFile && contactAddress === keyFile.pub_key;
+
+  // Auto-materialise the Saved Messages contact the first time the user
+  // opens chat-with-self. The contact is stored locally only — no on-chain
+  // CONTACT_REQUEST needed, since both ends are the same key pair.
+  useEffect(() => {
+    if (!isSavedMessages || !keyFile) return;
+    const existing = contacts.find(c => c.address === keyFile.pub_key);
+    if (existing) return;
+    upsertContact({
+      address:   keyFile.pub_key,
+      x25519Pub: keyFile.x25519_pub,
+      alias:     'Saved Messages',
+      addedAt:   Date.now(),
+    });
+  }, [isSavedMessages, keyFile, contacts, upsertContact]);
+
   const contact  = contacts.find(c => c.address === contactAddress);
   const chatMsgs = messages[contactAddress ?? ''] ?? [];
   const listRef  = useRef<FlatList>(null);
@@ -121,9 +139,9 @@ export default function ChatScreen() {
   // Восстановить сообщения из persistent-storage при первом заходе в чат.
   //
   // Важно: НЕ перезаписываем store пустым массивом — это стёрло бы
-  // содержимое, которое уже лежит в zustand (например, из devSeed или
-  // только что полученные по WS сообщения пока монтировались). Если
-  // в кэше что-то есть — мержим: берём max(cached, in-store) по id.
+  // содержимое, которое уже лежит в zustand (только что полученные по
+  // WS сообщения пока монтировались). Если в кэше что-то есть — мержим:
+  // берём max(cached, in-store) по id.
   useEffect(() => {
     if (!contactAddress) return;
     loadMessages(contactAddress).then(cached => {
@@ -137,7 +155,9 @@ export default function ChatScreen() {
     });
   }, [contactAddress, setMsgs]);
 
-  const name = contact?.username
+  const name = isSavedMessages
+    ? 'Saved Messages'
+    : contact?.username
       ? `@${contact.username}`
       : contact?.alias ?? shortAddr(contactAddress ?? '');
 
@@ -172,7 +192,7 @@ export default function ChatScreen() {
     const hasText   = !!actualText.trim();
     const hasAttach = !!actualAttach;
     if (!hasText && !hasAttach) return;
-    if (!contact.x25519Pub) {
+    if (!isSavedMessages && !contact.x25519Pub) {
       Alert.alert('No encryption key yet', 'The contact has not published their key. Try later.');
       return;
     }
@@ -188,16 +208,38 @@ export default function ChatScreen() {
 
     setSending(true);
     try {
-      if (hasText) {
+      // Saved Messages short-circuits the relay entirely — the message never
+      // leaves the device, so no encryption/fee/network round-trip is needed.
+      // Regular chats still go through the NaCl + relay pipeline below.
+      if (hasText && !isSavedMessages) {
+        // Multi-device fan-out (v2.2.0): resolve the recipient's active
+        // device X25519 pubs via /api/devices. Legacy identities (no
+        // devices registered) fall back to their published identity
+        // x25519 pub, preserving the pre-v2.2.0 single-device path.
+        // `contact.x25519Pub` stays the floor — if both network calls
+        // fail we still attempt delivery to the cached pub so a flaky
+        // connection doesn't block outgoing messages.
+        let recipientPubs = await resolveRecipientKeys(contact.address);
+        if (recipientPubs.length === 0 && contact.x25519Pub) {
+          recipientPubs = [contact.x25519Pub];
+        }
+        if (recipientPubs.length === 0) {
+          throw new Error('recipient has no encryption key published');
+        }
+        // One sealed envelope per recipient device. Parallel — slow
+        // relays don't block each other; any individual failure
+        // rejects the whole send (user retries).
+        await Promise.all(recipientPubs.map(async (rpub) => {
           const { nonce, ciphertext } = encryptMessage(
-          actualText.trim(), keyFile.x25519_priv, contact.x25519Pub,
+            actualText.trim(), keyFile.x25519_priv, rpub,
           );
           await sendEnvelope({
             senderPub:    keyFile.x25519_pub,
-          recipientPub: contact.x25519Pub,
+            recipientPub: rpub,
             senderEd25519Pub: keyFile.pub_key,
             nonce, ciphertext,
           });
+        }));
       }
 
       const msg: Message = {
@@ -224,7 +266,7 @@ export default function ChatScreen() {
       setSending(false);
     }
   }, [
-    text, keyFile, contact, composeMode, chatMsgs,
+    text, keyFile, contact, composeMode, chatMsgs, isSavedMessages,
     setMsgs, cancelCompose, appendMsg, pendingAttach,
   ]);
 
@@ -404,14 +446,14 @@ export default function ChatScreen() {
         ) : (
           <Header
             divider
-            left={<IconButton icon="chevron-back" size={36} onPress={() => router.back()} />}
+            left={<IconButton icon="chevron-back" size={36} onPress={() => safeBack()} />}
             title={
               <Pressable
                 onPress={onOpenPeerProfile}
                 hitSlop={4}
                 style={{ flexDirection: 'row', alignItems: 'center', gap: 8, maxWidth: '100%' }}
               >
-                <Avatar name={name} address={contactAddress} size={28} />
+                <Avatar name={name} address={contactAddress} size={28} saved={isSavedMessages} />
                 <View style={{ minWidth: 0, flexShrink: 1 }}>
                   <Text
                     numberOfLines={1}
@@ -429,7 +471,7 @@ export default function ChatScreen() {
                       typing…
                     </Text>
                   )}
-                  {!peerTyping && !contact?.x25519Pub && (
+                  {!peerTyping && !isSavedMessages && !contact?.x25519Pub && (
                     <Text style={{ color: '#f0b35a', fontSize: 11 }}>
                       waiting for key
                     </Text>
@@ -447,6 +489,32 @@ export default function ChatScreen() {
           с "scroll position at bottom" без ручного scrollToEnd, и новые
           сообщения (добавляемые в начало reversed-массива) появляются
           внизу естественно. Никаких jerk'ов при открытии. */}
+      {rows.length === 0 ? (
+        // Empty state is rendered as a plain View instead of
+        // ListEmptyComponent on an inverted FlatList — the previous
+        // `transform: [{ scaleY: -1 }]` un-flip trick was rendering
+        // text mirrored on some Android builds (RTL-aware layout),
+        // giving us the "say hi…" backwards bug.
+        <View style={{
+          flex: 1, alignItems: 'center', justifyContent: 'center',
+          paddingHorizontal: 32, gap: 10,
+        }}>
+          <Avatar
+            name={name}
+            address={contactAddress}
+            size={72}
+            saved={isSavedMessages}
+          />
+          <Text style={{ color: '#ffffff', fontSize: 16, fontWeight: '700', marginTop: 10 }}>
+            {isSavedMessages ? 'Notes to self' : `Say hi to ${name}`}
+          </Text>
+          <Text style={{ color: '#8b8b8b', fontSize: 13, textAlign: 'center', lineHeight: 20 }}>
+            {isSavedMessages
+              ? 'Anything you send here stays on your device — use it as a scratchpad for links, drafts, or files.'
+              : 'Your messages are end-to-end encrypted.'}
+          </Text>
+        </View>
+      ) : (
         <FlatList
           ref={listRef}
           data={rows}
@@ -462,22 +530,8 @@ export default function ChatScreen() {
           maxToRenderPerBatch={12}
           windowSize={10}
           removeClippedSubviews
-        ListEmptyComponent={() => (
-          <View style={{
-            flex: 1, alignItems: 'center', justifyContent: 'center',
-            paddingHorizontal: 32, gap: 10,
-            transform: [{ scaleY: -1 }],  // inverted flips cells; un-flip empty state
-          }}>
-            <Avatar name={name} address={contactAddress} size={72} />
-            <Text style={{ color: '#ffffff', fontSize: 16, fontWeight: '700', marginTop: 10 }}>
-              Say hi to {name}
-            </Text>
-            <Text style={{ color: '#8b8b8b', fontSize: 13, textAlign: 'center', lineHeight: 20 }}>
-              Your messages are end-to-end encrypted.
-            </Text>
-          </View>
-        )}
         />
+      )}
 
       {/* Composer — floating, прибит к низу. */}
       <View style={{ paddingBottom: Math.max(insets.bottom, 4) + 6, backgroundColor: '#000000' }}>

client-app/app/(app)/chats/index.tsx

@@ -28,6 +28,7 @@ export default function ChatsScreen() {
   const insets   = useSafeAreaInsets();
   const contacts = useStore(s => s.contacts);
   const messages = useStore(s => s.messages);
+  const keyFile  = useStore(s => s.keyFile);
 
   // Статус подключения: online / connecting / offline.
   // Название шапки и цвет pip'а на аватаре зависят от него.
@@ -48,9 +49,14 @@ export default function ChatsScreen() {
     return msgs && msgs.length ? msgs[msgs.length - 1] : null;
   };
 
-  // Сортировка по последней активности.
+  // Сортировка по последней активности. Saved Messages (self-chat) всегда
+  // закреплён сверху — это "Избранное", бессмысленно конкурировать с ним
+  // по recency'и обычным чатам.
+  const selfAddr = keyFile?.pub_key;
   const sorted = useMemo(() => {
-    return [...contacts]
+    const saved = selfAddr ? contacts.find(c => c.address === selfAddr) : undefined;
+    const rest = contacts
+      .filter(c => c.address !== selfAddr)
       .map(c => ({ c, last: lastOf(c) }))
       .sort((a, b) => {
         const ka = a.last ? a.last.timestamp : a.c.addedAt / 1000;
@@ -58,7 +64,8 @@ export default function ChatsScreen() {
         return kb - ka;
       })
       .map(x => x.c);
-  }, [contacts, messages]);
+    return saved ? [saved, ...rest] : rest;
+  }, [contacts, messages, selfAddr]);
 
   return (
     <View style={{ flex: 1, backgroundColor: '#000000', paddingTop: insets.top }}>
@@ -72,6 +79,7 @@ export default function ChatsScreen() {
             <ChatTile
               contact={item}
               lastMessage={lastOf(item)}
+              saved={item.address === selfAddr}
               onPress={() => router.push(`/(app)/chats/${item.address}` as never)}
             />
           )}

client-app/app/(app)/compose.tsx

@@ -37,11 +37,23 @@ import { useStore } from '@/lib/store';
 import { Avatar } from '@/components/Avatar';
 import { publishAndCommit, formatFee } from '@/lib/feed';
 import { humanizeTxError, getBalance } from '@/lib/api';
+import { safeBack } from '@/lib/utils';
 
 const MAX_CONTENT_LENGTH = 4000;
 const MAX_POST_BYTES     = 256 * 1024;   // must match server's MaxPostSize
 const IMAGE_MAX_DIM      = 1080;
-const IMAGE_QUALITY      = 0.5;           // JPEG Q=50 — small, still readable
+// Match the server scrubber's JPEG quality (media/scrub.go:ImageJPEGQuality
+// = 75). If the client re-encodes at a LOWER quality the server re-encode
+// at 75 inflates the bytes, often 2-3× — so a 60 KiB upload silently blows
+// past MaxPostSize = 256 KiB mid-flight and `/feed/publish` rejects with
+// "post body exceeds maximum allowed size". Using the same Q for both
+// passes keeps the final footprint ~the same as what the user sees in
+// the composer.
+const IMAGE_QUALITY      = 0.75;
+// Safety margin on the pre-upload check: the server pass is near-idempotent
+// at matching Q but not exactly — reserve ~8 KiB for JPEG header / metadata
+// scaffolding differences so we don't flirt with the hard cap.
+const IMAGE_BUDGET_BYTES = MAX_POST_BYTES - 8 * 1024;
 
 interface Attachment {
   uri:  string;
@@ -98,11 +110,11 @@ export default function ComposeScreen() {
       const perm = await ImagePicker.requestMediaLibraryPermissionsAsync();
       if (!perm.granted) {
         Alert.alert(
-          'Нужен доступ к фото',
-          'Откройте настройки и разрешите доступ к галерее.',
+          'Photo access required',
+          'Please enable photo library access in Settings.',
           [
-            { text: 'Отмена' },
-            { text: 'Настройки', onPress: () => Linking.openSettings() },
+            { text: 'Cancel' },
+            { text: 'Settings', onPress: () => Linking.openSettings() },
           ],
         );
         return;
@@ -130,10 +142,10 @@ export default function ComposeScreen() {
       });
       const bytes = base64ToBytes(b64);
 
-      if (bytes.length > MAX_POST_BYTES - 512) {
+      if (bytes.length > IMAGE_BUDGET_BYTES) {
         Alert.alert(
-          'Слишком большое',
-          `Картинка ${Math.round(bytes.length / 1024)} KB — лимит ${MAX_POST_BYTES / 1024} KB. Попробуйте выбрать поменьше.`,
+          'Image too large',
+          `Image is ${Math.round(bytes.length / 1024)} KB but the post limit is ${MAX_POST_BYTES / 1024} KB (after server re-encode). Try a smaller picture.`,
         );
         return;
       }
@@ -147,7 +159,7 @@ export default function ComposeScreen() {
         height: manipulated.height,
       });
     } catch (e: any) {
-      Alert.alert('Не удалось', String(e?.message ?? e));
+      Alert.alert('Failed', String(e?.message ?? e));
     } finally {
       setPicking(false);
     }
@@ -159,19 +171,19 @@ export default function ComposeScreen() {
     // Balance guard.
     if (balance !== null && balance < estimatedFee) {
       Alert.alert(
-        'Недостаточно средств',
-        `Нужно ${formatFee(estimatedFee)}, на балансе ${formatFee(balance)}.`,
+        'Insufficient balance',
+        `Need ${formatFee(estimatedFee)}, have ${formatFee(balance)}.`,
       );
       return;
     }
 
     Alert.alert(
-      'Опубликовать пост?',
-      `Цена: ${formatFee(estimatedFee)}\nРазмер: ${Math.round(totalBytes / 1024 * 10) / 10} KB`,
+      'Publish post?',
+      `Cost: ${formatFee(estimatedFee)}\nSize: ${Math.round(totalBytes / 1024 * 10) / 10} KB`,
       [
-        { text: 'Отмена', style: 'cancel' },
+        { text: 'Cancel', style: 'cancel' },
         {
-          text: 'Опубликовать',
+          text: 'Publish',
           onPress: async () => {
             setBusy(true);
             try {
@@ -185,7 +197,7 @@ export default function ComposeScreen() {
               // Close composer and open the new post.
               router.replace(`/(app)/feed/${postID}` as never);
             } catch (e: any) {
-              Alert.alert('Не удалось опубликовать', humanizeTxError(e));
+              Alert.alert('Failed to publish', humanizeTxError(e));
             } finally {
               setBusy(false);
             }
@@ -212,7 +224,7 @@ export default function ComposeScreen() {
           borderBottomColor: '#141414',
         }}
       >
-        <Pressable onPress={() => router.back()} hitSlop={8}>
+        <Pressable onPress={() => safeBack()} hitSlop={8}>
           <Ionicons name="close" size={26} color="#ffffff" />
         </Pressable>
         <View style={{ flex: 1 }} />
@@ -235,7 +247,7 @@ export default function ComposeScreen() {
                 fontSize: 14,
               }}
             >
-              Опубликовать
+              Publish
             </Text>
           )}
         </Pressable>
@@ -251,7 +263,7 @@ export default function ComposeScreen() {
           <TextInput
             value={content}
             onChangeText={setContent}
-            placeholder="Что происходит?"
+            placeholder="What's happening?"
             placeholderTextColor="#5a5a5a"
             multiline
             maxLength={MAX_CONTENT_LENGTH}
@@ -328,7 +340,7 @@ export default function ComposeScreen() {
               </Pressable>
             </View>
             <Text style={{ color: '#6a6a6a', fontSize: 11, marginTop: 6 }}>
-              {Math.round(attach.size / 1024)} KB · метаданные удалят на сервере
+              {Math.round(attach.size / 1024)} KB · metadata stripped on server
             </Text>
           </View>
         )}

client-app/app/(app)/devices.tsx

@@ -0,0 +1,490 @@
+/**
+ * Devices screen — Settings → Linked devices.
+ *
+ * Multi-device registry (v2.2.0). Lists every X25519 device published
+ * on-chain under this identity's master Ed25519 key. Operators can:
+ *   - see added-at timestamps
+ *   - rename this device (local alias for now; rename via LINK_DEVICE
+ *     with same pub + new name is a v2.3 polish)
+ *   - revoke a remote device via UNLINK_DEVICE (requires fee)
+ *   - pair a new device (Phase 3 — separate modal, stub for now)
+ *
+ * This device is NEVER listed with an Unlink button — revoking yourself
+ * is a footgun (you'd wipe your own state on next launch). Export/import
+ * your key first, then revoke from the new device.
+ */
+import React, { useCallback, useEffect, useState } from 'react';
+import {
+  View, Text, ScrollView, Pressable, ActivityIndicator, Alert, RefreshControl,
+  TextInput, KeyboardAvoidingView, Platform, Modal,
+} from 'react-native';
+import { Ionicons } from '@expo/vector-icons';
+import { useSafeAreaInsets } from 'react-native-safe-area-context';
+
+import { useStore } from '@/lib/store';
+import {
+  fetchDevices, buildLinkDeviceTx, buildUnlinkDeviceTx, submitTx,
+  sendEnvelope, humanizeTxError,
+  type DeviceInfo,
+} from '@/lib/api';
+import { encryptMessage } from '@/lib/crypto';
+import { Header } from '@/components/Header';
+import { IconButton } from '@/components/IconButton';
+import { safeBack } from '@/lib/utils';
+
+function shortPub(p: string, n = 8): string {
+  if (!p) return '—';
+  return p.length <= n * 2 + 1 ? p : `${p.slice(0, n)}…${p.slice(-n)}`;
+}
+
+function formatDate(unixSec: number): string {
+  return new Date(unixSec * 1000).toLocaleString();
+}
+
+export default function DevicesScreen() {
+  const insets  = useSafeAreaInsets();
+  const keyFile = useStore(s => s.keyFile);
+
+  const [devices, setDevices]       = useState<DeviceInfo[]>([]);
+  const [loading, setLoading]       = useState(true);
+  const [refreshing, setRefreshing] = useState(false);
+  const [unlinking, setUnlinking]   = useState<string | null>(null); // pub being revoked
+
+  const load = useCallback(async (isRefresh = false) => {
+    if (!keyFile) return;
+    if (isRefresh) setRefreshing(true);
+    else setLoading(true);
+    try {
+      const list = await fetchDevices(keyFile.pub_key);
+      setDevices(list);
+    } finally {
+      setLoading(false);
+      setRefreshing(false);
+    }
+  }, [keyFile]);
+
+  useEffect(() => { load(false); }, [load]);
+
+  const onUnlink = useCallback((dev: DeviceInfo) => {
+    if (!keyFile) return;
+    Alert.alert(
+      'Unlink device?',
+      `"${dev.device_name}" will stop receiving messages sent to you. ` +
+      `This costs a small network fee. The revoked device wipes its ` +
+      `local state the next time it checks in.`,
+      [
+        { text: 'Cancel', style: 'cancel' },
+        {
+          text: 'Unlink',
+          style: 'destructive',
+          onPress: async () => {
+            setUnlinking(dev.x25519_pub_key);
+            try {
+              const tx = buildUnlinkDeviceTx({
+                from:      keyFile.pub_key,
+                x25519Pub: dev.x25519_pub_key,
+                privKey:   keyFile.priv_key,
+              });
+              await submitTx(tx);
+              // Optimistic — drop from local list immediately; next load
+              // reconciles. Chain tx takes ~1 block to commit.
+              setDevices(prev => prev.filter(d => d.x25519_pub_key !== dev.x25519_pub_key));
+            } catch (e: any) {
+              Alert.alert('Unlink failed', humanizeTxError(e));
+            } finally {
+              setUnlinking(null);
+            }
+          },
+        },
+      ],
+    );
+  }, [keyFile]);
+
+  const meX25519 = keyFile?.x25519_pub ?? '';
+
+  // Pairing modal state — filled by the operator reading values off the
+  // new device's /auth/pair screen.
+  const [pairOpen, setPairOpen]             = useState(false);
+  const [pairCode, setPairCode]             = useState('');
+  const [pairKey,  setPairKey]              = useState('');
+  const [pairName, setPairName]             = useState('');
+  const [pairBusy, setPairBusy]             = useState(false);
+
+  const submitPair = useCallback(async () => {
+    if (!keyFile) return;
+    const code = pairCode.replace(/\s+/g, '').trim();
+    const key  = pairKey.replace(/\s+/g, '').trim().toLowerCase();
+    if (!/^\d{6}$/.test(code)) {
+      Alert.alert('Invalid code', 'The pairing code is 6 digits.');
+      return;
+    }
+    if (!/^[0-9a-f]{64}$/.test(key)) {
+      Alert.alert('Invalid key', 'The device key must be 64 hex characters.');
+      return;
+    }
+    const name = pairName.trim() || 'New device';
+    setPairBusy(true);
+    try {
+      // 1. LINK_DEVICE on-chain so senders learn the new pub.
+      const tx = buildLinkDeviceTx({
+        from:       keyFile.pub_key,
+        x25519Pub:  key,
+        deviceName: name,
+        privKey:    keyFile.priv_key,
+      });
+      await submitTx(tx);
+      // 2. Ship the handshake payload to the new device. Encrypted for
+      //    its x25519 pub so only it can read — master priv in plaintext
+      //    would be catastrophic, E2E is the whole point.
+      const payload = JSON.stringify({
+        v: 1,
+        type: 'pair-handshake',
+        code,
+        master_pub:        keyFile.pub_key,
+        master_priv:       keyFile.priv_key,
+        master_x25519_pub: keyFile.x25519_pub,
+      });
+      const { nonce, ciphertext } = encryptMessage(
+        payload, keyFile.x25519_priv, key,
+      );
+      await sendEnvelope({
+        senderPub:    keyFile.x25519_pub,
+        recipientPub: key,
+        senderEd25519Pub: keyFile.pub_key,
+        nonce, ciphertext,
+      });
+      // 3. Optimistic local insert so the row shows up without waiting
+      //    for the next pull/refresh round-trip.
+      setDevices(prev => {
+        if (prev.some(d => d.x25519_pub_key === key)) return prev;
+        return [...prev, {
+          x25519_pub_key: key,
+          device_name:    name,
+          added_at:       Math.floor(Date.now() / 1000),
+        }];
+      });
+      setPairOpen(false);
+      setPairCode(''); setPairKey(''); setPairName('');
+      Alert.alert(
+        'Pairing sent',
+        'The new device should finish pairing in a few seconds.',
+      );
+    } catch (e: any) {
+      Alert.alert('Pairing failed', humanizeTxError(e));
+    } finally {
+      setPairBusy(false);
+    }
+  }, [keyFile, pairCode, pairKey, pairName]);
+
+  return (
+    <View style={{ flex: 1, backgroundColor: '#000000', paddingTop: insets.top }}>
+      <Header
+        title="Devices"
+        divider
+        left={<IconButton icon="chevron-back" size={36} onPress={() => safeBack()} />}
+      />
+
+      <ScrollView
+        contentContainerStyle={{ padding: 14, paddingBottom: insets.bottom + 30 }}
+        refreshControl={
+          <RefreshControl
+            refreshing={refreshing}
+            onRefresh={() => load(true)}
+            tintColor="#1d9bf0"
+          />
+        }
+      >
+        <Text style={{ color: '#8b8b8b', fontSize: 12, lineHeight: 17, marginBottom: 14 }}>
+          Every linked device has its own encryption key. Messages sent to you
+          are delivered to all active devices.
+        </Text>
+
+        {loading ? (
+          <View style={{ paddingTop: 60, alignItems: 'center' }}>
+            <ActivityIndicator color="#1d9bf0" />
+          </View>
+        ) : devices.length === 0 ? (
+          <View style={{
+            paddingTop: 60, alignItems: 'center', paddingHorizontal: 24,
+          }}>
+            <Ionicons name="phone-portrait-outline" size={36} color="#3a3a3a" />
+            <Text style={{
+              color: '#ffffff', fontSize: 15, fontWeight: '700',
+              marginTop: 10,
+            }}>
+              No devices registered yet
+            </Text>
+            <Text style={{
+              color: '#8b8b8b', fontSize: 13, textAlign: 'center',
+              marginTop: 6, lineHeight: 19,
+            }}>
+              This device auto-registers when the next network-fee is available.
+              Top up your balance and pull to refresh.
+            </Text>
+          </View>
+        ) : (
+          <View style={{
+            borderRadius: 14,
+            backgroundColor: '#0a0a0a',
+            borderWidth: 1, borderColor: '#1f1f1f',
+            overflow: 'hidden',
+          }}>
+            {devices.map((d, i) => {
+              const isMe = d.x25519_pub_key === meX25519;
+              const busy = unlinking === d.x25519_pub_key;
+              return (
+                <View key={d.x25519_pub_key}>
+                  {i > 0 && <View style={{ height: 1, backgroundColor: '#1f1f1f' }} />}
+                  <View style={{
+                    flexDirection: 'row', alignItems: 'center',
+                    paddingHorizontal: 14, paddingVertical: 14, gap: 12,
+                  }}>
+                    <Ionicons
+                      name={isMe ? 'phone-portrait' : 'phone-portrait-outline'}
+                      size={22}
+                      color={isMe ? '#1d9bf0' : '#d0d0d0'}
+                    />
+                    <View style={{ flex: 1, minWidth: 0 }}>
+                      <View style={{ flexDirection: 'row', alignItems: 'center', gap: 6 }}>
+                        <Text
+                          style={{ color: '#ffffff', fontSize: 15, fontWeight: '700' }}
+                          numberOfLines={1}
+                        >
+                          {d.device_name || 'Unnamed device'}
+                        </Text>
+                        {isMe && (
+                          <View style={{
+                            paddingHorizontal: 6, paddingVertical: 1,
+                            borderRadius: 6, backgroundColor: '#0d2540',
+                          }}>
+                            <Text style={{ color: '#1d9bf0', fontSize: 10, fontWeight: '700' }}>
+                              THIS DEVICE
+                            </Text>
+                          </View>
+                        )}
+                      </View>
+                      <Text
+                        style={{
+                          color: '#8b8b8b', fontSize: 11, fontFamily: 'monospace',
+                          marginTop: 3,
+                        }}
+                        numberOfLines={1}
+                      >
+                        {shortPub(d.x25519_pub_key)}
+                      </Text>
+                      <Text style={{ color: '#6a6a6a', fontSize: 11, marginTop: 2 }}>
+                        Linked {formatDate(d.added_at)}
+                      </Text>
+                    </View>
+                    {!isMe && (
+                      <Pressable
+                        onPress={() => onUnlink(d)}
+                        disabled={busy}
+                        style={({ pressed }) => ({
+                          paddingHorizontal: 12, paddingVertical: 7,
+                          borderRadius: 999,
+                          borderWidth: 1, borderColor: '#3a2020',
+                          backgroundColor: pressed ? '#2a1414' : 'transparent',
+                          opacity: busy ? 0.5 : 1,
+                        })}
+                      >
+                        {busy ? (
+                          <ActivityIndicator size="small" color="#ff6b6b" />
+                        ) : (
+                          <Text style={{ color: '#ff6b6b', fontSize: 12, fontWeight: '700' }}>
+                            Unlink
+                          </Text>
+                        )}
+                      </Pressable>
+                    )}
+                  </View>
+                </View>
+              );
+            })}
+          </View>
+        )}
+
+        {/* Link new device — opens a modal with Code + DeviceKey inputs
+            that the operator transcribes from the new device's
+            /auth/pair screen. */}
+        <View style={{ marginTop: 18 }}>
+          <Pressable
+            onPress={() => setPairOpen(true)}
+            style={({ pressed }) => ({
+              paddingVertical: 13, paddingHorizontal: 16,
+              borderRadius: 14,
+              backgroundColor: pressed ? '#1a1a1a' : '#0a0a0a',
+              borderWidth: 1, borderColor: '#1f1f1f',
+              flexDirection: 'row', alignItems: 'center', gap: 10,
+            })}
+          >
+            <Ionicons name="link-outline" size={18} color="#1d9bf0" />
+            <View style={{ flex: 1 }}>
+              <Text style={{ color: '#ffffff', fontSize: 14, fontWeight: '700' }}>
+                Link new device
+              </Text>
+              <Text style={{ color: '#8b8b8b', fontSize: 12, marginTop: 2 }}>
+                Enter the 6-digit code from the new device
+              </Text>
+            </View>
+            <Ionicons name="chevron-forward" size={18} color="#6a6a6a" />
+          </Pressable>
+        </View>
+      </ScrollView>
+
+      {/* ── Pair new device modal ───────────────────────────────────── */}
+      <Modal
+        visible={pairOpen}
+        animationType="fade"
+        transparent
+        onRequestClose={() => !pairBusy && setPairOpen(false)}
+      >
+        <KeyboardAvoidingView
+          behavior={Platform.OS === 'ios' ? 'padding' : undefined}
+          style={{
+            flex: 1,
+            backgroundColor: 'rgba(0,0,0,0.7)',
+            justifyContent: 'center', alignItems: 'center',
+            paddingHorizontal: 20,
+          }}
+        >
+          <View style={{
+            width: '100%', maxWidth: 420,
+            backgroundColor: '#0a0a0a',
+            borderRadius: 18,
+            borderWidth: 1, borderColor: '#1f1f1f',
+            padding: 20, gap: 12,
+          }}>
+            <View style={{
+              flexDirection: 'row', alignItems: 'center',
+              justifyContent: 'space-between', marginBottom: 4,
+            }}>
+              <Text style={{ color: '#ffffff', fontSize: 18, fontWeight: '800' }}>
+                Link new device
+              </Text>
+              <Pressable
+                onPress={() => !pairBusy && setPairOpen(false)}
+                hitSlop={8}
+              >
+                <Ionicons name="close" size={22} color="#8b8b8b" />
+              </Pressable>
+            </View>
+
+            <Text style={{ color: '#8b8b8b', fontSize: 12, lineHeight: 18 }}>
+              Open the new device, tap <Text style={{ color: '#ffffff' }}>Pair</Text> on
+              the welcome screen, then transcribe the code + device key shown there.
+            </Text>
+
+            <PairInput
+              label="6-digit code"
+              value={pairCode}
+              onChangeText={setPairCode}
+              placeholder="000000"
+              keyboardType="number-pad"
+              maxLength={6}
+              monospace
+            />
+            <PairInput
+              label="Device key"
+              value={pairKey}
+              onChangeText={setPairKey}
+              placeholder="64 hex chars"
+              autoCapitalize="none"
+              maxLength={64}
+              monospace
+            />
+            <PairInput
+              label="Name for this device (optional)"
+              value={pairName}
+              onChangeText={setPairName}
+              placeholder="e.g. Alice's laptop"
+              maxLength={64}
+            />
+
+            <View style={{
+              flexDirection: 'row', justifyContent: 'flex-end',
+              gap: 10, marginTop: 8,
+            }}>
+              <Pressable
+                onPress={() => setPairOpen(false)}
+                disabled={pairBusy}
+                style={({ pressed }) => ({
+                  paddingHorizontal: 16, paddingVertical: 10,
+                  borderRadius: 999,
+                  backgroundColor: pressed ? '#1a1a1a' : 'transparent',
+                  opacity: pairBusy ? 0.5 : 1,
+                })}
+              >
+                <Text style={{ color: '#8b8b8b', fontSize: 14, fontWeight: '700' }}>
+                  Cancel
+                </Text>
+              </Pressable>
+              <Pressable
+                onPress={submitPair}
+                disabled={pairBusy}
+                style={({ pressed }) => ({
+                  paddingHorizontal: 18, paddingVertical: 10,
+                  borderRadius: 999,
+                  backgroundColor: pressed ? '#1580c8' : '#1d9bf0',
+                  opacity: pairBusy ? 0.7 : 1,
+                  minWidth: 90, alignItems: 'center',
+                })}
+              >
+                {pairBusy ? (
+                  <ActivityIndicator size="small" color="#ffffff" />
+                ) : (
+                  <Text style={{ color: '#ffffff', fontSize: 14, fontWeight: '700' }}>
+                    Link
+                  </Text>
+                )}
+              </Pressable>
+            </View>
+          </View>
+        </KeyboardAvoidingView>
+      </Modal>
+    </View>
+  );
+}
+
+function PairInput({
+  label, value, onChangeText, placeholder, keyboardType, autoCapitalize,
+  maxLength, monospace,
+}: {
+  label: string;
+  value: string;
+  onChangeText: (v: string) => void;
+  placeholder?: string;
+  keyboardType?: 'default' | 'number-pad';
+  autoCapitalize?: 'none' | 'sentences';
+  maxLength?: number;
+  monospace?: boolean;
+}) {
+  return (
+    <View>
+      <Text style={{
+        color: '#8b8b8b', fontSize: 11, fontWeight: '700',
+        textTransform: 'uppercase', letterSpacing: 1, marginBottom: 6,
+      }}>
+        {label}
+      </Text>
+      <TextInput
+        value={value}
+        onChangeText={onChangeText}
+        placeholder={placeholder}
+        placeholderTextColor="#3a3a3a"
+        keyboardType={keyboardType}
+        autoCapitalize={autoCapitalize ?? 'sentences'}
+        autoCorrect={false}
+        maxLength={maxLength}
+        style={{
+          color: '#ffffff', fontSize: monospace ? 13 : 14,
+          fontFamily: monospace ? 'monospace' : undefined,
+          backgroundColor: '#000000',
+          borderRadius: 10,
+          paddingHorizontal: 12, paddingVertical: 10,
+          borderWidth: 1, borderColor: '#1f1f1f',
+        }}
+      />
+    </View>
+  );
+}

client-app/app/(app)/feed/[id].tsx

@@ -31,6 +31,7 @@ import {
   fetchPost, fetchStats, bumpView, formatCount, formatFee,
   type FeedPostItem, type PostStats,
 } from '@/lib/feed';
+import { safeBack } from '@/lib/utils';
 
 export default function PostDetailScreen() {
   const insets = useSafeAreaInsets();
@@ -71,15 +72,15 @@ export default function PostDetailScreen() {
 
   const onDeleted = useCallback(() => {
     // Go back to feed — the post is gone.
-    router.back();
+    safeBack();
   }, []);
 
   return (
     <View style={{ flex: 1, backgroundColor: '#000000', paddingTop: insets.top }}>
       <Header
         divider
-        left={<IconButton icon="chevron-back" size={36} onPress={() => router.back()} />}
-        title="Пост"
+        left={<IconButton icon="chevron-back" size={36} onPress={() => safeBack()} />}
+        title="Post"
       />
 
       {loading ? (
@@ -94,7 +95,7 @@ export default function PostDetailScreen() {
         <View style={{ padding: 24, alignItems: 'center' }}>
           <Ionicons name="trash-outline" size={32} color="#6a6a6a" />
           <Text style={{ color: '#8b8b8b', marginTop: 10 }}>
-            Пост удалён или больше недоступен
+            Post deleted or no longer available
           </Text>
         </View>
       ) : (
@@ -131,18 +132,18 @@ export default function PostDetailScreen() {
               textTransform: 'uppercase',
               marginBottom: 10,
             }}>
-              Информация о посте
+              Post details
             </Text>
 
-            <DetailRow label="Просмотров" value={formatCount(stats?.views ?? post.views)} />
-            <DetailRow label="Лайков"     value={formatCount(stats?.likes ?? post.likes)} />
-            <DetailRow label="Размер"     value={`${Math.round(post.size / 1024 * 10) / 10} KB`} />
+            <DetailRow label="Views" value={formatCount(stats?.views ?? post.views)} />
+            <DetailRow label="Likes" value={formatCount(stats?.likes ?? post.likes)} />
+            <DetailRow label="Size"  value={`${Math.round(post.size / 1024 * 10) / 10} KB`} />
             <DetailRow
-              label="Стоимость публикации"
+              label="Paid to publish"
               value={formatFee(1000 + post.size)}
             />
             <DetailRow
-              label="Хостинг"
+              label="Hosted on"
               value={shortAddr(post.hosting_relay)}
               mono
             />
@@ -151,7 +152,7 @@ export default function PostDetailScreen() {
               <>
                 <View style={{ height: 1, backgroundColor: '#1f1f1f', marginVertical: 10 }} />
                 <Text style={{ color: '#5a5a5a', fontSize: 11, marginBottom: 6 }}>
-                  Хештеги
+                  Hashtags
                 </Text>
                 <View style={{ flexDirection: 'row', flexWrap: 'wrap', gap: 6 }}>
                   {post.hashtags.map(tag => (

client-app/app/(app)/feed/author/[pub].tsx

@@ -0,0 +1,249 @@
+/**
+ * Author wall — timeline of every post by a single author, newest first.
+ *
+ * Route: /(app)/feed/author/[pub]
+ *
+ * Entry points:
+ *   - Profile screen "View posts" button.
+ *   - Tapping the author name/avatar inside a PostCard.
+ *
+ * Backend: GET /feed/author/{pub}?limit=N[&before=ts]
+ *   — chain-authoritative, returns FeedPostItem[] ordered newest-first.
+ *
+ * Pagination: infinite-scroll via onEndReached → appends the next page
+ * anchored on the oldest timestamp we've seen. Safe to over-fetch because
+ * the relay caps `limit`.
+ */
+import React, { useCallback, useEffect, useRef, useState } from 'react';
+import {
+  View, Text, FlatList, RefreshControl, ActivityIndicator, Pressable,
+} from 'react-native';
+import { Ionicons } from '@expo/vector-icons';
+import { router, useLocalSearchParams } from 'expo-router';
+import { useSafeAreaInsets } from 'react-native-safe-area-context';
+
+import { Header } from '@/components/Header';
+import { IconButton } from '@/components/IconButton';
+import { Avatar } from '@/components/Avatar';
+import { PostCard, PostSeparator } from '@/components/feed/PostCard';
+import { useStore } from '@/lib/store';
+import { fetchAuthorPosts, fetchStats, type FeedPostItem } from '@/lib/feed';
+import { getIdentity, type IdentityInfo } from '@/lib/api';
+import { safeBack } from '@/lib/utils';
+
+const PAGE = 30;
+
+function shortAddr(a: string, n = 6): string {
+  if (!a) return '—';
+  return a.length <= n * 2 + 1 ? a : `${a.slice(0, n)}…${a.slice(-n)}`;
+}
+
+export default function AuthorWallScreen() {
+  const insets = useSafeAreaInsets();
+  const { pub } = useLocalSearchParams<{ pub: string }>();
+  const keyFile  = useStore(s => s.keyFile);
+  const contacts = useStore(s => s.contacts);
+
+  const contact  = contacts.find(c => c.address === pub);
+  const isMe     = !!keyFile && keyFile.pub_key === pub;
+
+  const [posts, setPosts]             = useState<FeedPostItem[]>([]);
+  const [likedSet, setLikedSet]       = useState<Set<string>>(new Set());
+  const [loading, setLoading]         = useState(true);
+  const [refreshing, setRefreshing]   = useState(false);
+  const [loadingMore, setLoadingMore] = useState(false);
+  const [exhausted, setExhausted]     = useState(false);
+  const [identity, setIdentity]       = useState<IdentityInfo | null>(null);
+
+  const seq = useRef(0);
+
+  // Identity — for the header's username / avatar seed. Best-effort; the
+  // screen still works without it.
+  useEffect(() => {
+    if (!pub) return;
+    let cancelled = false;
+    getIdentity(pub).then(id => { if (!cancelled) setIdentity(id); }).catch(() => {});
+    return () => { cancelled = true; };
+  }, [pub]);
+
+  const loadLikedFor = useCallback(async (items: FeedPostItem[]) => {
+    if (!keyFile) return new Set<string>();
+    const liked = new Set<string>();
+    for (const p of items) {
+      const s = await fetchStats(p.post_id, keyFile.pub_key);
+      if (s?.liked_by_me) liked.add(p.post_id);
+    }
+    return liked;
+  }, [keyFile]);
+
+  const load = useCallback(async (isRefresh = false) => {
+    if (!pub) return;
+    if (isRefresh) setRefreshing(true);
+    else setLoading(true);
+
+    const id = ++seq.current;
+    try {
+      const items = await fetchAuthorPosts(pub, { limit: PAGE });
+      if (id !== seq.current) return;
+      setPosts(items);
+      setExhausted(items.length < PAGE);
+      const liked = await loadLikedFor(items);
+      if (id !== seq.current) return;
+      setLikedSet(liked);
+    } catch {
+      if (id !== seq.current) return;
+      setPosts([]);
+      setExhausted(true);
+    } finally {
+      if (id !== seq.current) return;
+      setLoading(false);
+      setRefreshing(false);
+    }
+  }, [pub, loadLikedFor]);
+
+  useEffect(() => { load(false); }, [load]);
+
+  const loadMore = useCallback(async () => {
+    if (!pub || loadingMore || exhausted || loading) return;
+    const oldest = posts[posts.length - 1];
+    if (!oldest) return;
+    setLoadingMore(true);
+    try {
+      const more = await fetchAuthorPosts(pub, { limit: PAGE, before: oldest.created_at });
+      // De-dup by post_id — defensive against boundary overlap.
+      const known = new Set(posts.map(p => p.post_id));
+      const fresh = more.filter(p => !known.has(p.post_id));
+      if (fresh.length === 0) { setExhausted(true); return; }
+      setPosts(prev => [...prev, ...fresh]);
+      if (more.length < PAGE) setExhausted(true);
+      const liked = await loadLikedFor(fresh);
+      setLikedSet(set => {
+        const next = new Set(set);
+        liked.forEach(v => next.add(v));
+        return next;
+      });
+    } catch {
+      // Swallow — user can pull-to-refresh to recover.
+    } finally {
+      setLoadingMore(false);
+    }
+  }, [pub, posts, loadingMore, exhausted, loading, loadLikedFor]);
+
+  const onStatsChanged = useCallback(async (postID: string) => {
+    if (!keyFile) return;
+    const s = await fetchStats(postID, keyFile.pub_key);
+    if (!s) return;
+    setPosts(ps => ps.map(p => p.post_id === postID
+      ? { ...p, likes: s.likes, views: s.views } : p));
+    setLikedSet(set => {
+      const next = new Set(set);
+      if (s.liked_by_me) next.add(postID); else next.delete(postID);
+      return next;
+    });
+  }, [keyFile]);
+
+  // "Saved Messages" is a messaging-app label and has no place on a public
+  // wall — for self we fall back to the real handle (@username if claimed,
+  // else short-addr), same as any other author.
+  const displayName = isMe
+    ? (identity?.nickname ? `@${identity.nickname}` : 'You')
+    : contact?.username
+      ? `@${contact.username}`
+      : (contact?.alias && contact.alias !== 'Saved Messages')
+        ? contact.alias
+        : (identity?.nickname ? `@${identity.nickname}` : shortAddr(pub ?? '', 6));
+
+  const handle = identity?.nickname ? `@${identity.nickname}` : shortAddr(pub ?? '', 6);
+
+  return (
+    <View style={{ flex: 1, backgroundColor: '#000000', paddingTop: insets.top }}>
+      <Header
+        divider
+        left={<IconButton icon="chevron-back" size={36} onPress={() => safeBack()} />}
+        title={
+          <Pressable
+            onPress={() => pub && router.push(`/(app)/profile/${pub}` as never)}
+            hitSlop={4}
+            style={{ flexDirection: 'row', alignItems: 'center', gap: 8, maxWidth: '100%' }}
+          >
+            <Avatar name={displayName} address={pub} size={28} />
+            <View style={{ minWidth: 0, flexShrink: 1 }}>
+              <Text
+                numberOfLines={1}
+                style={{
+                  color: '#ffffff', fontSize: 15, fontWeight: '700', letterSpacing: -0.2,
+                }}
+              >
+                {displayName}
+              </Text>
+              <Text style={{ color: '#8b8b8b', fontSize: 11 }} numberOfLines={1}>
+                {handle !== displayName ? handle : 'Wall'}
+              </Text>
+            </View>
+          </Pressable>
+        }
+      />
+
+      <FlatList
+        data={posts}
+        keyExtractor={p => p.post_id}
+        renderItem={({ item }) => (
+          <PostCard
+            post={item}
+            likedByMe={likedSet.has(item.post_id)}
+            onStatsChanged={onStatsChanged}
+          />
+        )}
+        ItemSeparatorComponent={PostSeparator}
+        initialNumToRender={10}
+        maxToRenderPerBatch={8}
+        windowSize={7}
+        removeClippedSubviews
+        onEndReachedThreshold={0.6}
+        onEndReached={loadMore}
+        refreshControl={
+          <RefreshControl
+            refreshing={refreshing}
+            onRefresh={() => load(true)}
+            tintColor="#1d9bf0"
+          />
+        }
+        ListFooterComponent={
+          loadingMore ? (
+            <View style={{ paddingVertical: 18 }}>
+              <ActivityIndicator color="#1d9bf0" />
+            </View>
+          ) : null
+        }
+        ListEmptyComponent={
+          loading ? (
+            <View style={{ paddingTop: 80, alignItems: 'center' }}>
+              <ActivityIndicator color="#1d9bf0" />
+            </View>
+          ) : (
+            <View style={{
+              flex: 1,
+              alignItems: 'center', justifyContent: 'center',
+              paddingHorizontal: 32, paddingVertical: 80,
+            }}>
+              <Ionicons name="document-text-outline" size={32} color="#6a6a6a" />
+              <Text style={{ color: '#ffffff', fontWeight: '700', marginTop: 10 }}>
+                {isMe ? "You haven't posted yet" : 'No posts yet'}
+              </Text>
+              <Text style={{ color: '#8b8b8b', textAlign: 'center', fontSize: 13, marginTop: 6 }}>
+                {isMe
+                  ? 'Tap the compose button on the feed tab to publish your first post.'
+                  : 'This user hasn\'t published any posts on this chain.'}
+              </Text>
+            </View>
+          )
+        }
+        contentContainerStyle={
+          posts.length === 0
+            ? { flexGrow: 1 }
+            : { paddingTop: 8, paddingBottom: 24 }
+        }
+      />
+    </View>
+  );
+}

client-app/app/(app)/feed/index.tsx

@@ -27,14 +27,13 @@ import {
   fetchTimeline, fetchForYou, fetchTrending, fetchStats, bumpView,
   type FeedPostItem,
 } from '@/lib/feed';
-import { getDevSeedFeed } from '@/lib/devSeedFeed';
 
 type TabKey = 'following' | 'foryou' | 'trending';
 
 const TAB_LABELS: Record<TabKey, string> = {
-  following: 'Подписки',
-  foryou:    'Для вас',
-  trending:  'В тренде',
+  following: 'Following',
+  foryou:    'For you',
+  trending:  'Trending',
 };
 
 export default function FeedScreen() {
@@ -78,12 +77,6 @@ export default function FeedScreen() {
       }
       if (seq !== requestRef.current) return;   // stale response
 
-      // Dev-only fallback: if the node has no real posts yet, surface
-      // synthetic ones so we can scroll + tap. Stripped from production.
-      if (items.length === 0) {
-        items = getDevSeedFeed();
-      }
-
       setPosts(items);
       // If the server returned fewer than PAGE_SIZE, we already have
       // everything — disable further paginated fetches.
@@ -105,11 +98,11 @@ export default function FeedScreen() {
     } catch (e: any) {
       if (seq !== requestRef.current) return;
       const msg = String(e?.message ?? e);
-      // Network / 404 is benign — node just unreachable or empty. In __DEV__
-      // fall back to synthetic seed posts so the scroll / tap UI stays
-      // testable; in production this path shows the empty state.
+      // Network / 404 is benign — node just unreachable or empty. Show
+      // the empty-state; the catch block above already cleared error
+      // on benign messages. Production treats this identically.
       if (/Network request failed|→\s*404/.test(msg)) {
-        setPosts(getDevSeedFeed());
+        setPosts([]);
         setExhausted(true);
       } else {
         setError(msg);
@@ -208,15 +201,15 @@ export default function FeedScreen() {
 
   const emptyHint = useMemo(() => {
     switch (tab) {
-      case 'following': return 'Подпишитесь на кого-нибудь, чтобы увидеть их посты здесь.';
-      case 'foryou':    return 'Пока нет рекомендаций — возвращайтесь позже.';
-      case 'trending':  return 'В этой ленте пока тихо.';
+      case 'following': return 'Follow someone to see their posts here.';
+      case 'foryou':    return 'No recommendations yet — come back later.';
+      case 'trending':  return 'Nothing trending yet.';
     }
   }, [tab]);
 
   return (
     <View style={{ flex: 1, backgroundColor: '#000000', paddingTop: insets.top }}>
-      <TabHeader title="Лента" />
+      <TabHeader title="Feed" />
 
       {/* Tab strip — три таба, равномерно распределены по ширине
           (justifyContent: space-between). Каждый Pressable hug'ает
@@ -312,14 +305,14 @@ export default function FeedScreen() {
           ) : error ? (
             <EmptyState
               icon="alert-circle-outline"
-              title="Не удалось загрузить ленту"
+              title="Couldn't load feed"
               subtitle={error}
               onRetry={() => loadPosts(false)}
             />
           ) : (
             <EmptyState
               icon="newspaper-outline"
-              title="Здесь пока пусто"
+              title="Nothing to show yet"
               subtitle={emptyHint}
             />
           )
@@ -416,7 +409,7 @@ function EmptyState({
           })}
         >
           <Text style={{ color: '#ffffff', fontWeight: '700', fontSize: 13 }}>
-            Попробовать снова
+            Try again
           </Text>
         </Pressable>
       )}

client-app/app/(app)/feed/tag/[tag].tsx

@@ -17,6 +17,7 @@ import { IconButton } from '@/components/IconButton';
 import { PostCard, PostSeparator } from '@/components/feed/PostCard';
 import { useStore } from '@/lib/store';
 import { fetchHashtag, fetchStats, type FeedPostItem } from '@/lib/feed';
+import { safeBack } from '@/lib/utils';
 
 export default function HashtagScreen() {
   const insets = useSafeAreaInsets();
@@ -80,7 +81,7 @@ export default function HashtagScreen() {
     <View style={{ flex: 1, backgroundColor: '#000000', paddingTop: insets.top }}>
       <Header
         divider
-        left={<IconButton icon="chevron-back" size={36} onPress={() => router.back()} />}
+        left={<IconButton icon="chevron-back" size={36} onPress={() => safeBack()} />}
         title={`#${tag}`}
       />
 
@@ -119,10 +120,10 @@ export default function HashtagScreen() {
             }}>
               <Ionicons name="pricetag-outline" size={32} color="#6a6a6a" />
               <Text style={{ color: '#ffffff', fontWeight: '700', marginTop: 10 }}>
-                Пока нет постов с этим тегом
+                No posts with this tag yet
               </Text>
               <Text style={{ color: '#8b8b8b', textAlign: 'center', fontSize: 13, marginTop: 6 }}>
-                Будьте первым — напишите пост с #{tag}
+                Be the first — write a post with #{tag}
               </Text>
             </View>
           )

client-app/app/(app)/new-contact.tsx

@@ -18,7 +18,7 @@ import { useSafeAreaInsets } from 'react-native-safe-area-context';
 import { useStore } from '@/lib/store';
 import { getIdentity, buildContactRequestTx, submitTx, resolveUsername, humanizeTxError } from '@/lib/api';
 import { shortAddr } from '@/lib/crypto';
-import { formatAmount } from '@/lib/utils';
+import { formatAmount, safeBack } from '@/lib/utils';
 
 import { Avatar } from '@/components/Avatar';
 import { Header } from '@/components/Header';
@@ -64,9 +64,21 @@ export default function NewContactScreen() {
         if (!addr) { setError(`@${name} is not registered on this chain`); return; }
         address = addr;
       }
+      // Self-lookup: skip the contact-request dance entirely and jump straight
+      // to Saved Messages (self-chat). No CONTACT_REQUEST tx is needed — the
+      // chat-with-self flow is purely local storage.
+      if (keyFile && address.toLowerCase() === keyFile.pub_key.toLowerCase()) {
+        router.replace(`/(app)/chats/${keyFile.pub_key}` as never);
+        return;
+      }
       const identity = await getIdentity(address);
+      const resolvedAddr = identity?.pub_key ?? address;
+      if (keyFile && resolvedAddr.toLowerCase() === keyFile.pub_key.toLowerCase()) {
+        router.replace(`/(app)/chats/${keyFile.pub_key}` as never);
+        return;
+      }
       setResolved({
-        address:  identity?.pub_key ?? address,
+        address:  resolvedAddr,
         nickname: identity?.nickname || undefined,
         x25519:   identity?.x25519_pub || undefined,
       });
@@ -79,8 +91,12 @@ export default function NewContactScreen() {
 
   async function sendRequest() {
     if (!resolved || !keyFile) return;
+    if (resolved.address.toLowerCase() === keyFile.pub_key.toLowerCase()) {
+      Alert.alert('Can\'t message yourself', "This is your own address.");
+      return;
+    }
     if (balance < fee + 1000) {
-      Alert.alert('Insufficient balance', `Need ${formatAmount(fee + 1000)} (fee + network).`);
+      Alert.alert('Insufficient balance', `Need ${formatAmount(fee + 1000)} (request fee + network).`);
       return;
     }
     setSending(true); setError(null);
@@ -96,7 +112,7 @@ export default function NewContactScreen() {
       Alert.alert(
         'Request sent',
         `A contact request has been sent to ${resolved.nickname ? '@' + resolved.nickname : shortAddr(resolved.address)}.`,
-        [{ text: 'OK', onPress: () => router.back() }],
+        [{ text: 'OK', onPress: () => safeBack() }],
       );
     } catch (e: any) {
       setError(humanizeTxError(e));
@@ -112,34 +128,32 @@ export default function NewContactScreen() {
   return (
     <View style={{ flex: 1, backgroundColor: '#000000', paddingTop: insets.top }}>
       <Header
-        title="New chat"
+        title="Search"
         divider={false}
-        left={<IconButton icon="chevron-back" size={36} onPress={() => router.back()} />}
+        left={<IconButton icon="chevron-back" size={36} onPress={() => safeBack()} />}
       />
       <ScrollView
         contentContainerStyle={{ padding: 14, paddingBottom: 120 }}
         keyboardShouldPersistTaps="handled"
         showsVerticalScrollIndicator={false}
       >
-        <Text style={{ color: '#8b8b8b', fontSize: 13, lineHeight: 19, marginBottom: 14 }}>
-          Enter a <Text style={{ color: '#ffffff', fontWeight: '600' }}>@username</Text>, a
-          hex pubkey or a <Text style={{ color: '#ffffff', fontWeight: '600' }}>DC…</Text> address.
-        </Text>
-
         <SearchBar
           value={query}
           onChangeText={setQuery}
-          placeholder="@alice or hex / DC address"
+          placeholder="@alice, hex pubkey or DC address"
           onSubmitEditing={search}
+          autoFocus
+          onClear={() => { setResolved(null); setError(null); }}
         />
 
+        {query.trim().length > 0 && (
           <Pressable
             onPress={search}
-          disabled={searching || !query.trim()}
+            disabled={searching}
             style={({ pressed }) => ({
               flexDirection: 'row', alignItems: 'center', justifyContent: 'center',
               paddingVertical: 11, borderRadius: 999, marginTop: 12,
-            backgroundColor: !query.trim() || searching ? '#1a1a1a' : pressed ? '#1a8cd8' : '#1d9bf0',
+              backgroundColor: searching ? '#1a1a1a' : pressed ? '#1a8cd8' : '#1d9bf0',
             })}
           >
             {searching ? (
@@ -148,6 +162,31 @@ export default function NewContactScreen() {
               <Text style={{ color: '#ffffff', fontWeight: '700', fontSize: 14 }}>Search</Text>
             )}
           </Pressable>
+        )}
+
+        {/* Empty-state hint — показываем когда ничего не введено и нет результата */}
+        {query.trim().length === 0 && !resolved && (
+          <View style={{ marginTop: 28, alignItems: 'center', paddingHorizontal: 16 }}>
+            <View
+              style={{
+                width: 56, height: 56, borderRadius: 16,
+                backgroundColor: '#0a0a0a',
+                borderWidth: 1, borderColor: '#1f1f1f',
+                alignItems: 'center', justifyContent: 'center',
+                marginBottom: 12,
+              }}
+            >
+              <Ionicons name="person-add-outline" size={24} color="#6a6a6a" />
+            </View>
+            <Text style={{ color: '#ffffff', fontSize: 15, fontWeight: '700', marginBottom: 6 }}>
+              Find someone to message
+            </Text>
+            <Text style={{ color: '#8b8b8b', fontSize: 13, textAlign: 'center', lineHeight: 19 }}>
+              Enter an <Text style={{ color: '#ffffff', fontWeight: '600' }}>@username</Text> if
+              the person registered one, or paste a full hex pubkey or <Text style={{ color: '#ffffff', fontWeight: '600' }}>DC…</Text> address.
+            </Text>
+          </View>
+        )}
 
         {error && (
           <View style={{
@@ -195,7 +234,7 @@ export default function NewContactScreen() {
                       color: resolved.x25519 ? '#3ba55d' : '#f0b35a',
                       fontSize: 11, fontWeight: '500',
                     }}>
-                      {resolved.x25519 ? 'E2E-ready' : 'Key not published yet'}
+                      {resolved.x25519 ? 'E2E ready' : 'Key not published yet'}
                     </Text>
                   </View>
                 </View>
@@ -227,8 +266,16 @@ export default function NewContactScreen() {
 
             {/* Fee tier */}
             <Text style={{ color: '#8b8b8b', fontSize: 12, marginTop: 14, marginBottom: 6 }}>
-              Anti-spam fee (goes to recipient)
+              Anti-spam fee (goes to the recipient)
             </Text>
+            {/* Fee-tier pills.
+                Layout (background, border, padding) lives on a static
+                inner View — Pressable's dynamic style-function has been
+                observed to drop backgroundColor between renders on
+                some RN/Android versions, which is what made these
+                chips look like three bare text labels on black
+                instead of distinct pills. Press feedback via opacity
+                on the Pressable itself, which is stable. */}
             <View style={{ flexDirection: 'row', gap: 8 }}>
               {FEE_TIERS.map(t => {
                 const active = fee === t.value;
@@ -238,12 +285,18 @@ export default function NewContactScreen() {
                     onPress={() => setFee(t.value)}
                     style={({ pressed }) => ({
                       flex: 1,
+                      opacity: pressed ? 0.7 : 1,
+                    })}
+                  >
+                    <View
+                      style={{
                         alignItems: 'center',
                         paddingVertical: 10,
                         borderRadius: 10,
-                      backgroundColor: active ? '#ffffff' : pressed ? '#1a1a1a' : '#111111',
-                      borderWidth: 1, borderColor: active ? '#ffffff' : '#1f1f1f',
-                    })}
+                        backgroundColor: active ? '#ffffff' : '#111111',
+                        borderWidth: 1,
+                        borderColor: active ? '#ffffff' : '#1f1f1f',
+                      }}
                     >
                       <Text style={{
                         color: active ? '#000' : '#ffffff',
@@ -257,6 +310,7 @@ export default function NewContactScreen() {
                       }}>
                         {formatAmount(t.value)}
                       </Text>
+                    </View>
                   </Pressable>
                 );
               })}

client-app/app/(app)/profile/[address].tsx

@@ -13,7 +13,7 @@
  *   push stack, so tapping Back returns the user to whatever screen
  *   pushed them here (feed card tap, chat header tap, etc.).
  */
-import React, { useState } from 'react';
+import React, { useEffect, useState } from 'react';
 import {
   View, Text, ScrollView, Pressable, ActivityIndicator,
 } from 'react-native';
@@ -27,7 +27,11 @@ import { Avatar } from '@/components/Avatar';
 import { Header } from '@/components/Header';
 import { IconButton } from '@/components/IconButton';
 import { followUser, unfollowUser } from '@/lib/feed';
-import { humanizeTxError } from '@/lib/api';
+import {
+  humanizeTxError, getBalance, getIdentity, getRelayFor,
+  type IdentityInfo, type RegisteredRelayInfo,
+} from '@/lib/api';
+import { safeBack, formatAmount } from '@/lib/utils';
 
 function shortAddr(a: string, n = 10): string {
   if (!a) return '—';
@@ -45,10 +49,35 @@ export default function ProfileScreen() {
   const [followingBusy, setFollowingBusy] = useState(false);
   const [copied, setCopied]             = useState(false);
 
+  // On-chain enrichment — fetched once per address mount.
+  const [balanceUT, setBalanceUT] = useState<number | null>(null);
+  const [identity, setIdentity]   = useState<IdentityInfo | null>(null);
+  const [relay, setRelay]         = useState<RegisteredRelayInfo | null>(null);
+  const [loadingChain, setLoadingChain] = useState(true);
+
   const isMe = !!keyFile && keyFile.pub_key === address;
-  const displayName = contact?.username
+
+  useEffect(() => {
+    if (!address) return;
+    let cancelled = false;
+    setLoadingChain(true);
+    Promise.all([
+      getBalance(address).catch(() => 0),
+      getIdentity(address).catch(() => null),
+      getRelayFor(address).catch(() => null),
+    ]).then(([bal, id, rel]) => {
+      if (cancelled) return;
+      setBalanceUT(bal);
+      setIdentity(id);
+      setRelay(rel);
+    }).finally(() => { if (!cancelled) setLoadingChain(false); });
+    return () => { cancelled = true; };
+  }, [address]);
+  const displayName = isMe
+    ? 'Saved Messages'
+    : contact?.username
       ? `@${contact.username}`
-    : contact?.alias ?? (isMe ? 'Вы' : shortAddr(address ?? '', 6));
+      : contact?.alias ?? shortAddr(address ?? '', 6);
 
   const copyAddress = async () => {
     if (!address) return;
@@ -85,15 +114,15 @@ export default function ProfileScreen() {
   return (
     <View style={{ flex: 1, backgroundColor: '#000000', paddingTop: insets.top }}>
       <Header
-        title="Профиль"
+        title="Profile"
         divider
-        left={<IconButton icon="chevron-back" size={36} onPress={() => router.back()} />}
+        left={<IconButton icon="chevron-back" size={36} onPress={() => safeBack()} />}
       />
 
       <ScrollView contentContainerStyle={{ padding: 14, paddingBottom: insets.bottom + 30 }}>
         {/* ── Hero: avatar + Follow button ──────────────────────────── */}
         <View style={{ flexDirection: 'row', alignItems: 'flex-end', marginBottom: 12 }}>
-          <Avatar name={displayName} address={address} size={72} />
+          <Avatar name={displayName} address={address} size={72} saved={isMe} />
           <View style={{ flex: 1 }} />
           {!isMe ? (
             <Pressable
@@ -124,22 +153,24 @@ export default function ProfileScreen() {
                     fontSize: 13,
                   }}
                 >
-                  {following ? 'Вы подписаны' : 'Подписаться'}
+                  {following ? 'Following' : 'Follow'}
                 </Text>
               )}
             </Pressable>
           ) : (
             <Pressable
-              onPress={() => router.push('/(app)/settings' as never)}
+              onPress={() => keyFile && router.push(`/(app)/chats/${keyFile.pub_key}` as never)}
               style={({ pressed }) => ({
-                paddingHorizontal: 18, paddingVertical: 9,
+                paddingHorizontal: 16, paddingVertical: 9,
                 borderRadius: 999,
+                flexDirection: 'row', alignItems: 'center', gap: 6,
                 backgroundColor: pressed ? '#1a1a1a' : '#111111',
                 borderWidth: 1, borderColor: '#1f1f1f',
               })}
             >
+              <Ionicons name="bookmark" size={13} color="#f0b35a" />
               <Text style={{ color: '#ffffff', fontWeight: '700', fontSize: 13 }}>
-                Редактировать
+                Saved Messages
               </Text>
             </Pressable>
           )}
@@ -158,13 +189,35 @@ export default function ProfileScreen() {
           )}
         </View>
 
-        {/* Open chat — single CTA, full width, icon inline with text.
-            Only when we know this is a contact (direct chat exists). */}
+        {/* Action row — View posts is universal (anyone can have a wall,
+            even non-contacts). Open chat appears alongside only when this
+            address is already a direct-chat contact. */}
+        <View style={{ flexDirection: 'row', gap: 8, marginTop: 14 }}>
+          <Pressable
+            onPress={() => address && router.push(`/(app)/feed/author/${address}` as never)}
+            style={({ pressed }) => ({
+              flex: 1,
+              flexDirection: 'row',
+              alignItems: 'center',
+              justifyContent: 'center',
+              gap: 6,
+              paddingVertical: 11,
+              borderRadius: 999,
+              backgroundColor: pressed ? '#1a1a1a' : '#111111',
+              borderWidth: 1, borderColor: '#1f1f1f',
+            })}
+          >
+            <Ionicons name="document-text-outline" size={15} color="#ffffff" />
+            <Text style={{ color: '#ffffff', fontWeight: '600', fontSize: 14 }}>
+              View posts
+            </Text>
+          </Pressable>
+
           {!isMe && contact && (
             <Pressable
               onPress={openChat}
               style={({ pressed }) => ({
-              marginTop: 14,
+                flex: 1,
                 flexDirection: 'row',
                 alignItems: 'center',
                 justifyContent: 'center',
@@ -177,10 +230,11 @@ export default function ProfileScreen() {
             >
               <Ionicons name="chatbubble-outline" size={15} color="#ffffff" />
               <Text style={{ color: '#ffffff', fontWeight: '600', fontSize: 14 }}>
-              Открыть чат
+                Open chat
               </Text>
             </Pressable>
           )}
+        </View>
 
         {/* ── Info card ───────────────────────────────────────────────── */}
         <View
@@ -203,7 +257,7 @@ export default function ProfileScreen() {
             })}
           >
             <Text style={{ color: '#8b8b8b', fontSize: 13, flex: 1 }}>
-              Адрес
+              Address
             </Text>
             <Text
               style={{
@@ -214,7 +268,7 @@ export default function ProfileScreen() {
               }}
               numberOfLines={1}
             >
-              {copied ? 'Скопировано' : shortAddr(address ?? '')}
+              {copied ? 'Copied' : shortAddr(address ?? '')}
             </Text>
             <Ionicons
               name={copied ? 'checkmark' : 'copy-outline'}
@@ -224,22 +278,79 @@ export default function ProfileScreen() {
             />
           </Pressable>
 
+          {/* Username — shown if the on-chain identity record has one.
+              Different from contact.username (which may be a local alias). */}
+          {identity?.nickname ? (
+            <>
+              <Divider />
+              <InfoRow
+                label="Username"
+                value={`@${identity.nickname}`}
+                icon="at-outline"
+              />
+            </>
+          ) : null}
+
+          {/* DC address — the human-readable form of the pub key. */}
+          {identity?.address ? (
+            <>
+              <Divider />
+              <InfoRow
+                label="DC address"
+                value={identity.address}
+                icon="pricetag-outline"
+              />
+            </>
+          ) : null}
+
+          {/* Balance — always shown once fetched. */}
+          <Divider />
+          <InfoRow
+            label="Balance"
+            value={loadingChain
+              ? '…'
+              : `${formatAmount(balanceUT ?? 0)} UT`}
+            icon="wallet-outline"
+          />
+
+          {/* Relay node — shown only if this address is a registered relay. */}
+          {relay && (
+            <>
+              <Divider />
+              <InfoRow
+                label="Relay node"
+                value={`${formatAmount(relay.relay.fee_per_msg_ut)} UT / msg`}
+                icon="radio-outline"
+              />
+              {relay.last_heartbeat ? (
+                <>
+                  <Divider />
+                  <InfoRow
+                    label="Last seen"
+                    value={new Date(relay.last_heartbeat * 1000).toLocaleString()}
+                    icon="pulse-outline"
+                  />
+                </>
+              ) : null}
+            </>
+          )}
+
           {/* Encryption status */}
           {contact && (
             <>
               <Divider />
               <InfoRow
-                label="Шифрование"
+                label="Encryption"
                 value={contact.x25519Pub
                   ? 'end-to-end (NaCl)'
-                  : 'ключ ещё не опубликован'}
+                  : 'key not published yet'}
                 danger={!contact.x25519Pub}
                 icon={contact.x25519Pub ? 'lock-closed' : 'lock-open'}
               />
 
               <Divider />
               <InfoRow
-                label="Добавлен"
+                label="Added"
                 value={new Date(contact.addedAt).toLocaleDateString()}
                 icon="calendar-outline"
               />
@@ -251,7 +362,7 @@ export default function ProfileScreen() {
                 <>
                   <Divider />
                   <InfoRow
-                    label="Участников"
+                    label="Members"
                     value="—"
                     icon="people-outline"
                   />
@@ -270,7 +381,7 @@ export default function ProfileScreen() {
             paddingHorizontal: 24,
             lineHeight: 17,
           }}>
-            Этот пользователь пока не в ваших контактах. Нажмите «Подписаться», чтобы видеть его посты в ленте, или добавьте в чаты через @username.
+            This user isn't in your contacts yet. Tap "Follow" to see their posts in your feed, or add them as a chat contact via @username.
           </Text>
         )}
       </ScrollView>

client-app/app/(app)/requests.tsx

@@ -91,7 +91,7 @@ export default function RequestsScreen() {
             {name}
           </Text>
           <Text style={{ color: '#8b8b8b', fontSize: 12, marginTop: 2 }}>
-            wants to message you · {relativeTime(req.timestamp)}
+            wants to add you as a contact · {relativeTime(req.timestamp)}
           </Text>
           {req.intro ? (
             <Text

client-app/app/(app)/settings.tsx

@@ -32,7 +32,7 @@ import {
   humanizeTxError,
 } from '@/lib/api';
 import { shortAddr } from '@/lib/crypto';
-import { formatAmount } from '@/lib/utils';
+import { formatAmount, safeBack } from '@/lib/utils';
 
 import { Avatar } from '@/components/Avatar';
 import { Header } from '@/components/Header';
@@ -335,7 +335,7 @@ export default function SettingsScreen() {
       <Header
         title="Settings"
         divider={false}
-        left={<IconButton icon="chevron-back" size={36} onPress={() => router.back()} />}
+        left={<IconButton icon="chevron-back" size={36} onPress={() => safeBack()} />}
       />
       <ScrollView
         contentContainerStyle={{ paddingBottom: 120 }}
@@ -492,6 +492,18 @@ export default function SettingsScreen() {
           />
         </Card>
 
+        {/* ── Devices — multi-device registry (v2.2.0) ── */}
+        <SectionLabel>Devices</SectionLabel>
+        <Card>
+          <Row
+            icon="phone-portrait-outline"
+            label="Linked devices"
+            value="Manage the devices that receive your messages"
+            onPress={() => router.push('/(app)/devices' as never)}
+            first
+          />
+        </Card>
+
         {/* ── Account ── */}
         <SectionLabel>Account</SectionLabel>
         <Card>

client-app/app/(app)/tx/[id].tsx

@@ -0,0 +1,427 @@
+/**
+ * Transaction detail screen — shows everything the block explorer
+ * does for a single tx, so the user can audit any action they took
+ * (transfer, post, like, contact request) without leaving the app.
+ *
+ * Route: /(app)/tx/[id]
+ *
+ * Triggered from: wallet history (TxTile tap). Will also be reachable
+ * from post detail / profile timestamp once we wire those up (Phase
+ * v2.1 idea).
+ *
+ * Layout matches the style of the profile info card:
+ *   [back] Transaction
+ *
+ *   [ICON]  <TYPE>
+ *           <relative time> · <status>
+ *
+ *   [amount pill, big, signed ± + tone colour]  (for TRANSFER-ish)
+ *
+ *   Info card rows:
+ *     ID            <hash>                 (tap → copy)
+ *     From          <addr>                 (tap → copy)
+ *     To            <addr>                 (tap → copy)
+ *     Block         #N
+ *     Time          <human>
+ *     Fee           0.001 T
+ *     Gas           1234 (if CALL_CONTRACT)
+ *     Memo          (if set)
+ *
+ *   [payload section, collapsible — raw JSON or hex]
+ */
+import React, { useCallback, useEffect, useState } from 'react';
+import {
+  View, Text, ScrollView, ActivityIndicator, Pressable,
+} from 'react-native';
+import * as Clipboard from 'expo-clipboard';
+import { Ionicons } from '@expo/vector-icons';
+import { useLocalSearchParams } from 'expo-router';
+import { useSafeAreaInsets } from 'react-native-safe-area-context';
+
+import { Header } from '@/components/Header';
+import { IconButton } from '@/components/IconButton';
+import { getTxDetail, type TxDetail } from '@/lib/api';
+import { useStore } from '@/lib/store';
+import { safeBack, formatAmount } from '@/lib/utils';
+
+function shortAddr(a: string, n = 8): string {
+  if (!a) return '—';
+  return a.length <= n * 2 + 1 ? a : `${a.slice(0, n)}…${a.slice(-n)}`;
+}
+
+// Copy of the tx-type metadata used by wallet.tsx — keeps the icon +
+// label consistent whichever screen surfaces the tx.
+function txMeta(type: string): {
+  icon: React.ComponentProps<typeof Ionicons>['name'];
+  label: string;
+  tone: 'in' | 'out' | 'neutral';
+} {
+  switch (type) {
+    case 'TRANSFER':         return { icon: 'swap-horizontal',  label: 'Transfer',          tone: 'neutral' };
+    case 'CONTACT_REQUEST':  return { icon: 'person-add',       label: 'Contact request',   tone: 'out' };
+    case 'ACCEPT_CONTACT':   return { icon: 'checkmark-circle', label: 'Accepted contact',  tone: 'neutral' };
+    case 'BLOCK_CONTACT':    return { icon: 'ban',              label: 'Blocked contact',   tone: 'neutral' };
+    case 'REGISTER_KEY':     return { icon: 'key',              label: 'Identity registered', tone: 'neutral' };
+    case 'REGISTER_RELAY':   return { icon: 'globe',            label: 'Relay registered',  tone: 'neutral' };
+    case 'BIND_WALLET':      return { icon: 'wallet',           label: 'Wallet bound',      tone: 'neutral' };
+    case 'RELAY_PROOF':      return { icon: 'receipt',          label: 'Relay proof',       tone: 'in'  };
+    case 'BLOCK_REWARD':     return { icon: 'trophy',           label: 'Block reward',      tone: 'in'  };
+    case 'HEARTBEAT':        return { icon: 'pulse',            label: 'Heartbeat',         tone: 'neutral' };
+    case 'CREATE_POST':      return { icon: 'newspaper',        label: 'Post published',    tone: 'out' };
+    case 'DELETE_POST':      return { icon: 'trash',            label: 'Post deleted',      tone: 'neutral' };
+    case 'LIKE_POST':        return { icon: 'heart',            label: 'Like',              tone: 'neutral' };
+    case 'UNLIKE_POST':      return { icon: 'heart-dislike',    label: 'Unlike',            tone: 'neutral' };
+    case 'FOLLOW':           return { icon: 'person-add',       label: 'Follow',            tone: 'neutral' };
+    case 'UNFOLLOW':         return { icon: 'person-remove',    label: 'Unfollow',          tone: 'neutral' };
+    case 'CALL_CONTRACT':    return { icon: 'terminal',         label: 'Contract call',     tone: 'neutral' };
+    case 'DEPLOY_CONTRACT':  return { icon: 'cube',             label: 'Contract deployed', tone: 'neutral' };
+    case 'STAKE':            return { icon: 'lock-closed',      label: 'Stake',             tone: 'out' };
+    case 'UNSTAKE':          return { icon: 'lock-open',        label: 'Unstake',           tone: 'in'  };
+    default:                 return { icon: 'document',         label: type || 'Transaction', tone: 'neutral' };
+  }
+}
+
+function toneColor(tone: 'in' | 'out' | 'neutral'): string {
+  if (tone === 'in')  return '#3ba55d';
+  if (tone === 'out') return '#f4212e';
+  return '#ffffff';
+}
+
+export default function TxDetailScreen() {
+  const insets  = useSafeAreaInsets();
+  const { id }  = useLocalSearchParams<{ id: string }>();
+  const keyFile = useStore(s => s.keyFile);
+
+  const [tx, setTx]           = useState<TxDetail | null>(null);
+  const [loading, setLoading] = useState(true);
+  const [error, setError]     = useState<string | null>(null);
+  const [copied, setCopied]   = useState<string | null>(null);
+  const [payloadOpen, setPayloadOpen] = useState(false);
+
+  useEffect(() => {
+    if (!id) return;
+    let cancelled = false;
+    setLoading(true);
+    setError(null);
+    getTxDetail(id)
+      .then(res => { if (!cancelled) setTx(res); })
+      .catch(e => { if (!cancelled) setError(String(e?.message ?? e)); })
+      .finally(() => { if (!cancelled) setLoading(false); });
+    return () => { cancelled = true; };
+  }, [id]);
+
+  const copy = useCallback(async (field: string, value: string) => {
+    await Clipboard.setStringAsync(value);
+    setCopied(field);
+    setTimeout(() => setCopied(f => (f === field ? null : f)), 1500);
+  }, []);
+
+  const meta = tx ? txMeta(tx.type) : null;
+  const mine = keyFile?.pub_key ?? '';
+  const isMineOut = tx ? tx.from === mine && tx.to !== mine : false;
+  const isMineIn  = tx ? tx.to === mine && tx.from !== mine : false;
+  const showAmount = tx ? tx.amount_ut > 0 : false;
+  // Sign based on perspective: money leaving my wallet → minus, coming in → plus.
+  const sign = isMineOut ? '−' : isMineIn ? '+' : '';
+  const amountColor =
+    isMineOut ? '#f4212e'
+    : isMineIn ? '#3ba55d'
+    : '#ffffff';
+
+  return (
+    <View style={{ flex: 1, backgroundColor: '#000000', paddingTop: insets.top }}>
+      <Header
+        title="Transaction"
+        divider
+        left={<IconButton icon="chevron-back" size={36} onPress={() => safeBack()} />}
+      />
+
+      {loading ? (
+        <View style={{ flex: 1, alignItems: 'center', justifyContent: 'center' }}>
+          <ActivityIndicator color="#1d9bf0" />
+        </View>
+      ) : error ? (
+        <View style={{ padding: 24 }}>
+          <Text style={{ color: '#f4212e', fontSize: 14 }}>{error}</Text>
+        </View>
+      ) : !tx ? (
+        <View style={{ flex: 1, alignItems: 'center', justifyContent: 'center', paddingHorizontal: 32 }}>
+          <Ionicons name="help-circle-outline" size={40} color="#3a3a3a" />
+          <Text style={{ color: '#ffffff', fontSize: 16, fontWeight: '700', marginTop: 10 }}>
+            Not found
+          </Text>
+          <Text style={{ color: '#8b8b8b', fontSize: 13, textAlign: 'center', marginTop: 6 }}>
+            No transaction with this ID on this chain.
+          </Text>
+        </View>
+      ) : (
+        <ScrollView contentContainerStyle={{ padding: 14, paddingBottom: 40 }}>
+          {/* ── Hero row: icon + type + time ───────────────────────── */}
+          <View style={{ flexDirection: 'row', alignItems: 'center', marginBottom: 16 }}>
+            <View
+              style={{
+                width: 48, height: 48, borderRadius: 14,
+                backgroundColor: '#111111',
+                borderWidth: 1, borderColor: '#1f1f1f',
+                alignItems: 'center', justifyContent: 'center',
+                marginRight: 12,
+              }}
+            >
+              <Ionicons name={meta!.icon} size={22} color="#ffffff" />
+            </View>
+            <View style={{ flex: 1, minWidth: 0 }}>
+              <Text style={{ color: '#ffffff', fontSize: 17, fontWeight: '700' }}>
+                {meta!.label}
+              </Text>
+              <Text style={{ color: '#8b8b8b', fontSize: 12, marginTop: 2 }}>
+                {new Date(tx.time).toLocaleString()}
+              </Text>
+            </View>
+          </View>
+
+          {/* ── Amount big number — only for txs that move tokens ── */}
+          {showAmount && (
+            <View
+              style={{
+                alignItems: 'center',
+                paddingVertical: 18,
+                borderRadius: 14,
+                backgroundColor: '#0a0a0a',
+                borderWidth: 1, borderColor: '#1f1f1f',
+                marginBottom: 14,
+              }}
+            >
+              <Text style={{
+                color: amountColor,
+                fontSize: 32,
+                fontWeight: '800',
+                letterSpacing: -0.8,
+              }}>
+                {sign}{formatAmount(tx.amount_ut)}
+              </Text>
+              <Text style={{ color: '#6a6a6a', fontSize: 11, marginTop: 2 }}>
+                {tx.amount}
+              </Text>
+            </View>
+          )}
+
+          {/* ── Info card ───────────────────────────────────────────── */}
+          <View
+            style={{
+              borderRadius: 14,
+              backgroundColor: '#0a0a0a',
+              borderWidth: 1, borderColor: '#1f1f1f',
+              overflow: 'hidden',
+            }}
+          >
+            <CopyRow
+              label="Tx ID"
+              value={shortAddr(tx.id, 8)}
+              rawValue={tx.id}
+              field="id"
+              copied={copied}
+              onCopy={copy}
+              mono
+            />
+            <Divider />
+            <CopyRow
+              label="From"
+              value={shortAddr(tx.from, 8)}
+              rawValue={tx.from}
+              field="from"
+              copied={copied}
+              onCopy={copy}
+              mono
+              highlight={tx.from === mine ? 'you' : undefined}
+            />
+            {tx.to && (
+              <>
+                <Divider />
+                <CopyRow
+                  label="To"
+                  value={shortAddr(tx.to, 8)}
+                  rawValue={tx.to}
+                  field="to"
+                  copied={copied}
+                  onCopy={copy}
+                  mono
+                  highlight={tx.to === mine ? 'you' : undefined}
+                />
+              </>
+            )}
+            <Divider />
+            <InfoRow label="Block" value={`#${tx.block_index}`} />
+            <Divider />
+            <InfoRow label="Fee" value={formatAmount(tx.fee_ut)} />
+            {tx.gas_used ? (
+              <>
+                <Divider />
+                <InfoRow label="Gas used" value={String(tx.gas_used)} />
+              </>
+            ) : null}
+            {tx.memo ? (
+              <>
+                <Divider />
+                <InfoRow label="Memo" value={tx.memo} />
+              </>
+            ) : null}
+          </View>
+
+          {/* ── Payload expand ─────────────────────────────────────── */}
+          {(tx.payload || tx.payload_hex) && (
+            <View style={{ marginTop: 14 }}>
+              <Pressable
+                onPress={() => setPayloadOpen(o => !o)}
+                style={({ pressed }) => ({
+                  flexDirection: 'row',
+                  alignItems: 'center',
+                  paddingVertical: 10,
+                  paddingHorizontal: 14,
+                  backgroundColor: pressed ? '#0f0f0f' : '#0a0a0a',
+                  borderWidth: 1, borderColor: '#1f1f1f',
+                  borderRadius: 14,
+                })}
+              >
+                <Ionicons name="code-slash" size={14} color="#8b8b8b" />
+                <Text style={{ color: '#ffffff', fontSize: 13, fontWeight: '600', marginLeft: 8, flex: 1 }}>
+                  Payload
+                </Text>
+                <Ionicons
+                  name={payloadOpen ? 'chevron-up' : 'chevron-down'}
+                  size={14}
+                  color="#6a6a6a"
+                />
+              </Pressable>
+              {payloadOpen && (
+                <View
+                  style={{
+                    marginTop: 8,
+                    padding: 12,
+                    borderRadius: 12,
+                    backgroundColor: '#050505',
+                    borderWidth: 1, borderColor: '#1f1f1f',
+                  }}
+                >
+                  <Text
+                    selectable
+                    style={{
+                      color: '#d0d0d0',
+                      fontSize: 11,
+                      fontFamily: 'monospace',
+                      lineHeight: 16,
+                    }}
+                  >
+                    {tx.payload
+                      ? JSON.stringify(tx.payload, null, 2)
+                      : `hex: ${tx.payload_hex}`}
+                  </Text>
+                </View>
+              )}
+            </View>
+          )}
+
+          {/* Signature as a final copyable row, small */}
+          {tx.signature_hex && (
+            <View
+              style={{
+                marginTop: 14,
+                borderRadius: 14,
+                backgroundColor: '#0a0a0a',
+                borderWidth: 1, borderColor: '#1f1f1f',
+                overflow: 'hidden',
+              }}
+            >
+              <CopyRow
+                label="Signature"
+                value={shortAddr(tx.signature_hex, 10)}
+                rawValue={tx.signature_hex}
+                field="signature"
+                copied={copied}
+                onCopy={copy}
+                mono
+              />
+            </View>
+          )}
+        </ScrollView>
+      )}
+    </View>
+  );
+}
+
+// ── Rows ──────────────────────────────────────────────────────────────
+
+function Divider() {
+  return <View style={{ height: 1, backgroundColor: '#1f1f1f' }} />;
+}
+
+function InfoRow({ label, value }: { label: string; value: string }) {
+  return (
+    <View
+      style={{
+        flexDirection: 'row',
+        alignItems: 'center',
+        paddingHorizontal: 14,
+        paddingVertical: 12,
+      }}
+    >
+      <Text style={{ color: '#8b8b8b', fontSize: 13, flex: 1 }}>{label}</Text>
+      <Text style={{ color: '#ffffff', fontSize: 13, fontWeight: '600' }} numberOfLines={1}>
+        {value}
+      </Text>
+    </View>
+  );
+}
+
+function CopyRow({
+  label, value, rawValue, field, copied, onCopy, mono, highlight,
+}: {
+  label: string;
+  value: string;
+  rawValue: string;
+  field: string;
+  copied: string | null;
+  onCopy: (field: string, value: string) => void;
+  mono?: boolean;
+  highlight?: 'you';
+}) {
+  const isCopied = copied === field;
+  return (
+    <Pressable
+      onPress={() => onCopy(field, rawValue)}
+      style={({ pressed }) => ({
+        flexDirection: 'row',
+        alignItems: 'center',
+        paddingHorizontal: 14,
+        paddingVertical: 12,
+        backgroundColor: pressed ? '#0f0f0f' : 'transparent',
+      })}
+    >
+      <Text style={{ color: '#8b8b8b', fontSize: 13, flex: 1 }}>{label}</Text>
+      <Text
+        style={{
+          color: isCopied
+            ? '#3ba55d'
+            : highlight === 'you'
+              ? '#1d9bf0'
+              : '#ffffff',
+          fontSize: 13,
+          fontFamily: mono ? 'monospace' : undefined,
+          fontWeight: '600',
+          marginRight: 8,
+        }}
+        numberOfLines={1}
+      >
+        {isCopied
+          ? 'Copied'
+          : highlight === 'you'
+            ? `${value} (you)`
+            : value}
+      </Text>
+      <Ionicons
+        name={isCopied ? 'checkmark' : 'copy-outline'}
+        size={13}
+        color={isCopied ? '#3ba55d' : '#6a6a6a'}
+      />
+    </Pressable>
+  );
+}

client-app/app/(app)/tx/_layout.tsx

@@ -0,0 +1,19 @@
+/**
+ * Tx detail layout — native Stack so router.back() pops back to the
+ * screen that pushed us (wallet history, chat tx link, etc.) instead
+ * of falling through to the outer Slot-level root.
+ */
+import React from 'react';
+import { Stack } from 'expo-router';
+
+export default function TxLayout() {
+  return (
+    <Stack
+      screenOptions={{
+        headerShown: false,
+        contentStyle: { backgroundColor: '#000000' },
+        animation: 'slide_from_right',
+      }}
+    />
+  );
+}

client-app/app/(app)/wallet.tsx

@@ -17,6 +17,7 @@ import {
   View, Text, ScrollView, Modal, Alert, RefreshControl, Pressable, TextInput, ActivityIndicator,
 } from 'react-native';
 import * as Clipboard from 'expo-clipboard';
+import { router } from 'expo-router';
 import { Ionicons } from '@expo/vector-icons';
 import { useSafeAreaInsets } from 'react-native-safe-area-context';
 
@@ -346,7 +347,7 @@ function TxTile({
   const color = toneColor(m.tone);
 
   return (
-    <Pressable>
+    <Pressable onPress={() => router.push(`/(app)/tx/${tx.hash}` as never)}>
       <View
         style={{
           flexDirection: 'row',

client-app/app/(auth)/create.tsx

@@ -10,6 +10,7 @@ import { useSafeAreaInsets } from 'react-native-safe-area-context';
 import { generateKeyFile } from '@/lib/crypto';
 import { saveKeyFile } from '@/lib/storage';
 import { useStore } from '@/lib/store';
+import { safeBack } from '@/lib/utils';
 
 import { Header } from '@/components/Header';
 import { IconButton } from '@/components/IconButton';
@@ -37,7 +38,7 @@ export default function CreateAccountScreen() {
     <View style={{ flex: 1, backgroundColor: '#000000', paddingTop: insets.top }}>
       <Header
         title="Create account"
-        left={<IconButton icon="chevron-back" size={36} onPress={() => router.back()} />}
+        left={<IconButton icon="chevron-back" size={36} onPress={() => safeBack('/')} />}
       />
       <ScrollView contentContainerStyle={{ padding: 14, paddingBottom: 40 }}>
         <Text style={{ color: '#ffffff', fontSize: 17, fontWeight: '700', marginBottom: 4 }}>

client-app/app/(auth)/import.tsx

@@ -15,6 +15,7 @@ import * as DocumentPicker from 'expo-document-picker';
 import * as Clipboard from 'expo-clipboard';
 import { saveKeyFile } from '@/lib/storage';
 import { useStore } from '@/lib/store';
+import { safeBack } from '@/lib/utils';
 import type { KeyFile } from '@/lib/types';
 
 import { Header } from '@/components/Header';
@@ -96,7 +97,7 @@ export default function ImportKeyScreen() {
     <View style={{ flex: 1, backgroundColor: '#000000', paddingTop: insets.top }}>
       <Header
         title="Import key"
-        left={<IconButton icon="chevron-back" size={36} onPress={() => router.back()} />}
+        left={<IconButton icon="chevron-back" size={36} onPress={() => safeBack('/')} />}
       />
       <ScrollView
         contentContainerStyle={{ padding: 14, paddingBottom: 40 }}

client-app/app/(auth)/pair.tsx

@@ -0,0 +1,300 @@
+/**
+ * Pair — secondary-device onboarding.
+ *
+ * Flow (new device, this screen):
+ *   1. Generate a fresh X25519 keypair locally + random 6-digit code.
+ *   2. Display { code, device x25519 pub }. User enters both on their
+ *      primary device (Settings → Devices → Link new device).
+ *   3. Primary device:
+ *        - submits LINK_DEVICE tx to publish our pub under its master,
+ *        - sends a relay envelope to our x25519 pub, encrypted with its
+ *          own x25519 priv, containing { code, master_pub, master_priv,
+ *          master_x25519_pub }.
+ *   4. We poll /relay/inbox every few seconds; when a decryptable
+ *      envelope arrives whose payload.code matches our displayed code,
+ *      we treat it as the handshake, assemble a KeyFile, save it, and
+ *      redirect into (app).
+ *
+ * Security notes:
+ *   - Master Ed25519 priv travels only via this envelope, encrypted for
+ *     this device's X25519 pub (which only this device holds the priv
+ *     for). Exposure is limited to one successful decrypt; we DELETE
+ *     the envelope from the mailbox immediately.
+ *   - The 6-digit code defends against a confused primary device paired
+ *     with a different victim, or a race with an attacker who guesses
+ *     our X25519 pub. Envelope without matching code → ignored.
+ *   - Envelope is short-lived in the mailbox: we DELETE on first decrypt
+ *     and the relay node has its own TTL.
+ */
+import React, { useCallback, useEffect, useRef, useState } from 'react';
+import {
+  View, Text, Pressable, ActivityIndicator, ScrollView,
+} from 'react-native';
+import { router } from 'expo-router';
+import { Ionicons } from '@expo/vector-icons';
+import * as Clipboard from 'expo-clipboard';
+import { useSafeAreaInsets } from 'react-native-safe-area-context';
+import nacl from 'tweetnacl';
+
+import { useStore } from '@/lib/store';
+import { bytesToHex, decryptMessage } from '@/lib/crypto';
+import { fetchInbox } from '@/lib/api';
+import { saveKeyFile, markDeviceRegistered } from '@/lib/storage';
+import { safeBack } from '@/lib/utils';
+import type { KeyFile } from '@/lib/types';
+
+// Protocol constant — bump if payload shape changes.
+const PAIR_ENVELOPE_VERSION = 1;
+
+interface PairEnvelopePayload {
+  v:             number;
+  type:          'pair-handshake';
+  code:          string;
+  master_pub:    string;   // Ed25519 pub, hex
+  master_priv:   string;   // Ed25519 priv, hex
+  master_x25519_pub: string;  // primary device's x25519 pub, hex (for nothing special — just FYI)
+}
+
+function randomCode(): string {
+  // Six decimal digits. Entropy ~20 bits. Good enough for a one-shot
+  // rendezvous code gated by an out-of-band delivery channel (envelope
+  // targeted at a freshly-generated X25519 pub that only this device
+  // holds the priv for).
+  const n = Math.floor(Math.random() * 1_000_000);
+  return n.toString().padStart(6, '0');
+}
+
+export default function PairScreen() {
+  const insets       = useSafeAreaInsets();
+  const setKeyFile   = useStore(s => s.setKeyFile);
+
+  // One-shot keypair + code for this pairing session. Regenerate only on
+  // manual Retry (unmount+remount).
+  const session = useRef(genSession()).current;
+
+  const [status, setStatus] = useState<'waiting' | 'success' | 'error'>('waiting');
+  const [err,    setErr]    = useState<string | null>(null);
+
+  const copyCode = useCallback(async () => {
+    await Clipboard.setStringAsync(session.code);
+  }, [session.code]);
+
+  const copyPub = useCallback(async () => {
+    await Clipboard.setStringAsync(session.x25519Pub);
+  }, [session.x25519Pub]);
+
+  // Poll mailbox until a matching handshake envelope arrives, or user
+  // backs out. Interval 2.5s — conservative on battery, fine for a
+  // flow the user is staring at for a minute.
+  useEffect(() => {
+    let cancelled = false;
+    let timer: ReturnType<typeof setTimeout> | null = null;
+
+    const tick = async () => {
+      if (cancelled) return;
+      try {
+        const envs = await fetchInbox(session.x25519Pub);
+        for (const env of envs) {
+          // Decrypt each envelope with our session priv. We don't know
+          // the primary's x25519 pub up front — it's inside the envelope
+          // metadata. decryptMessage needs both pubs, so we pass the
+          // envelope's sender_pub directly.
+          const plain = decryptMessage(
+            env.ciphertext, env.nonce, env.sender_pub, session.x25519Priv,
+          );
+          if (!plain) continue;
+          let payload: PairEnvelopePayload;
+          try {
+            payload = JSON.parse(plain);
+          } catch { continue; }
+          if (
+            payload.v !== PAIR_ENVELOPE_VERSION ||
+            payload.type !== 'pair-handshake' ||
+            payload.code !== session.code ||
+            !payload.master_pub || !payload.master_priv
+          ) continue;
+
+          // Success — materialise a KeyFile and redirect.
+          const kf: KeyFile = {
+            pub_key:     payload.master_pub,
+            priv_key:    payload.master_priv,
+            x25519_pub:  session.x25519Pub,
+            x25519_priv: session.x25519Priv,
+          };
+          await saveKeyFile(kf);
+          // The root layout auto-links us on first boot if needed, but
+          // the primary device already submitted LINK_DEVICE for our
+          // pub as part of the pairing, so the registry is already
+          // correct. Mark ourselves registered so the revoke-detection
+          // branch doesn't spuriously wipe on next launch.
+          await markDeviceRegistered();
+          setKeyFile(kf);
+
+          // Envelope stays in mailbox until relay TTL eviction; the
+          // single-shot handshake is idempotent (saveKeyFile overwrites)
+          // and our session pub won't be polled again after redirect.
+          setStatus('success');
+          setTimeout(() => {
+            if (!cancelled) router.replace('/(app)/chats' as never);
+          }, 600);
+          return;
+        }
+      } catch {
+        /* transient — retry */
+      }
+      if (!cancelled) timer = setTimeout(tick, 2_500);
+    };
+
+    tick();
+    return () => {
+      cancelled = true;
+      if (timer) clearTimeout(timer);
+    };
+  }, [session, setKeyFile]);
+
+  return (
+    <View style={{
+      flex: 1, backgroundColor: '#000000',
+      paddingTop: insets.top + 12,
+      paddingBottom: Math.max(insets.bottom, 20),
+    }}>
+      <ScrollView
+        contentContainerStyle={{ padding: 24 }}
+        showsVerticalScrollIndicator={false}
+      >
+        {/* Header */}
+        <Pressable
+          onPress={() => safeBack('/')}
+          hitSlop={8}
+          style={{ alignSelf: 'flex-start', marginBottom: 20 }}
+        >
+          <Ionicons name="chevron-back" size={28} color="#ffffff" />
+        </Pressable>
+
+        <View style={{ alignItems: 'center', marginBottom: 28 }}>
+          <View style={{
+            width: 80, height: 80, borderRadius: 22,
+            backgroundColor: '#0a0a0a',
+            borderWidth: 1, borderColor: '#1f1f1f',
+            alignItems: 'center', justifyContent: 'center',
+          }}>
+            <Ionicons name="link" size={40} color="#1d9bf0" />
+          </View>
+          <Text style={{
+            color: '#ffffff', fontSize: 22, fontWeight: '800',
+            marginTop: 14, textAlign: 'center',
+          }}>
+            Pair with your other device
+          </Text>
+          <Text style={{
+            color: '#8b8b8b', fontSize: 13, lineHeight: 19,
+            marginTop: 8, textAlign: 'center', maxWidth: 300,
+          }}>
+            On a device where you're already signed in,
+            open Settings → Devices → Link new device,
+            and enter these values.
+          </Text>
+        </View>
+
+        {/* Code */}
+        <View style={{
+          borderRadius: 14,
+          backgroundColor: '#0a0a0a',
+          borderWidth: 1, borderColor: '#1f1f1f',
+          paddingVertical: 18, paddingHorizontal: 16,
+          marginBottom: 14, alignItems: 'center',
+        }}>
+          <Text style={{
+            color: '#5a5a5a', fontSize: 11, fontWeight: '700',
+            textTransform: 'uppercase', letterSpacing: 1.2,
+          }}>
+            1. Code
+          </Text>
+          <Text style={{
+            color: '#ffffff', fontSize: 38, fontWeight: '800',
+            letterSpacing: 6, marginTop: 4, fontFamily: 'monospace',
+          }}>
+            {session.code.slice(0, 3)} {session.code.slice(3)}
+          </Text>
+          <Pressable onPress={copyCode} hitSlop={6} style={{ marginTop: 6 }}>
+            <Text style={{ color: '#1d9bf0', fontSize: 12, fontWeight: '600' }}>
+              Copy code
+            </Text>
+          </Pressable>
+        </View>
+
+        {/* Device key */}
+        <View style={{
+          borderRadius: 14,
+          backgroundColor: '#0a0a0a',
+          borderWidth: 1, borderColor: '#1f1f1f',
+          paddingVertical: 16, paddingHorizontal: 16,
+          marginBottom: 20,
+        }}>
+          <Text style={{
+            color: '#5a5a5a', fontSize: 11, fontWeight: '700',
+            textTransform: 'uppercase', letterSpacing: 1.2,
+          }}>
+            2. Device key
+          </Text>
+          <Text
+            selectable
+            style={{
+              color: '#ffffff', fontSize: 12, fontFamily: 'monospace',
+              marginTop: 6, lineHeight: 17,
+            }}
+          >
+            {session.x25519Pub}
+          </Text>
+          <Pressable onPress={copyPub} hitSlop={6} style={{ marginTop: 8 }}>
+            <Text style={{ color: '#1d9bf0', fontSize: 12, fontWeight: '600' }}>
+              Copy key
+            </Text>
+          </Pressable>
+        </View>
+
+        {/* Status */}
+        <View style={{ alignItems: 'center', minHeight: 56 }}>
+          {status === 'waiting' && (
+            <View style={{ flexDirection: 'row', alignItems: 'center', gap: 10 }}>
+              <ActivityIndicator size="small" color="#1d9bf0" />
+              <Text style={{ color: '#8b8b8b', fontSize: 13 }}>
+                Waiting for your other device…
+              </Text>
+            </View>
+          )}
+          {status === 'success' && (
+            <View style={{ flexDirection: 'row', alignItems: 'center', gap: 10 }}>
+              <Ionicons name="checkmark-circle" size={20} color="#3ba55d" />
+              <Text style={{ color: '#3ba55d', fontSize: 13, fontWeight: '700' }}>
+                Paired. Opening your chats…
+              </Text>
+            </View>
+          )}
+          {status === 'error' && (
+            <Text style={{ color: '#f4212e', fontSize: 13, textAlign: 'center' }}>
+              {err ?? 'Something went wrong. Please retry.'}
+            </Text>
+          )}
+        </View>
+      </ScrollView>
+    </View>
+  );
+}
+
+// ─── session helper ──────────────────────────────────────────────────────
+
+interface PairSession {
+  x25519Pub:  string;  // hex
+  x25519Priv: string;  // hex
+  code:       string;
+}
+
+function genSession(): PairSession {
+  const kp = nacl.box.keyPair();
+  return {
+    x25519Pub:  bytesToHex(kp.publicKey),
+    x25519Priv: bytesToHex(kp.secretKey),
+    code:       randomCode(),
+  };
+}

client-app/app/index.tsx

@@ -187,17 +187,17 @@ export default function WelcomeScreen() {
             <FeatureRow
               icon="lock-closed"
               title="End-to-end encryption"
-              text="X25519 + NaCl на каждом сообщении. Даже релей-нода не может прочитать переписку."
+              text="X25519 + NaCl on every message. Not even the relay node can read your conversations."
             />
             <FeatureRow
               icon="key"
-              title="Твои ключи — твой аккаунт"
-              text="Без телефона, email и серверных паролей. Ключи никогда не покидают устройство."
+              title="Your keys, your account"
+              text="No phone, email, or server passwords. Keys never leave your device."
             />
             <FeatureRow
               icon="git-network"
               title="Decentralised"
-              text="Любой может поднять свою ноду. Нет единой точки отказа и цензуры."
+              text="Anyone can run a node. No single point of failure or censorship."
             />
           </ScrollView>
 
@@ -206,7 +206,7 @@ export default function WelcomeScreen() {
             flexDirection: 'row', justifyContent: 'flex-end',
             paddingHorizontal: 24, paddingBottom: 8,
           }}>
-            <CTAPrimary label="Продолжить" onPress={() => goToPage(1)} />
+            <CTAPrimary label="Continue" onPress={() => goToPage(1)} />
           </View>
         </View>
 
@@ -223,22 +223,22 @@ export default function WelcomeScreen() {
             keyboardShouldPersistTaps="handled"
           >
           <Text style={{ color: '#ffffff', fontSize: 24, fontWeight: '800', letterSpacing: -0.5 }}>
-            Как это работает
+            How it works
           </Text>
           <Text style={{ color: '#8b8b8b', fontSize: 14, lineHeight: 20, marginTop: 8, marginBottom: 22 }}>
-            Сообщения проходят через релей-ноду в зашифрованном виде.
-            Выбери публичную или подключи свою.
+            Messages travel through a relay node in encrypted form.
+            Pick a public one or run your own.
           </Text>
 
           <OptionCard
             icon="globe"
-            title="Публичная нода"
-            text="Удобно и быстро — нода хостится комьюнити, небольшая комиссия за каждое отправленное сообщение."
+            title="Public node"
+            text="Quick and easy — community-hosted relay, small fee per delivered message."
           />
           <OptionCard
             icon="hardware-chip"
-            title="Своя нода"
-            text="Максимальный контроль. Исходники открыты — подними на своём сервере за 5 минут."
+            title="Self-hosted"
+            text="Maximum control. Source is open — spin up your own in five minutes."
           />
 
           <Text style={{
@@ -302,11 +302,11 @@ export default function WelcomeScreen() {
             paddingHorizontal: 24, paddingBottom: 8,
           }}>
             <CTASecondary
-              label="Исходники"
+              label="Source"
               icon="logo-github"
               onPress={() => Linking.openURL(GITEA_URL).catch(() => {})}
             />
-            <CTAPrimary label="Продолжить" onPress={() => goToPage(2)} />
+            <CTAPrimary label="Continue" onPress={() => goToPage(2)} />
           </View>
         </View>
 
@@ -334,11 +334,11 @@ export default function WelcomeScreen() {
                 <Ionicons name="key" size={44} color="#1d9bf0" />
               </View>
               <Text style={{ color: '#ffffff', fontSize: 24, fontWeight: '800', letterSpacing: -0.5, textAlign: 'center' }}>
-                Твой аккаунт
+                Your account
               </Text>
               <Text style={{ color: '#8b8b8b', fontSize: 14, lineHeight: 20, marginTop: 8, textAlign: 'center', maxWidth: 280 }}>
-                Создай новую пару ключей или импортируй существующую.
-                Ключи хранятся только на этом устройстве.
+                Generate a fresh keypair or import an existing one.
+                Keys stay on this device only.
               </Text>
             </View>
           </ScrollView>
@@ -346,14 +346,19 @@ export default function WelcomeScreen() {
           {/* CTA — прижата к правому нижнему краю. */}
           <View style={{
             flexDirection: 'row', justifyContent: 'flex-end', gap: 10,
-            paddingHorizontal: 24, paddingBottom: 8,
+            paddingHorizontal: 24, paddingBottom: 8, flexWrap: 'wrap',
           }}>
             <CTASecondary
-              label="Импорт"
+              label="Pair"
+              icon="link"
+              onPress={() => router.push('/(auth)/pair' as never)}
+            />
+            <CTASecondary
+              label="Import"
               onPress={() => router.push('/(auth)/import' as never)}
             />
             <CTAPrimary
-              label="Создать аккаунт"
+              label="Create account"
               onPress={() => router.push('/(auth)/create' as never)}
             />
           </View>

client-app/components/Avatar.tsx

@@ -6,6 +6,7 @@
  */
 import React from 'react';
 import { View, Text } from 'react-native';
+import { Ionicons } from '@expo/vector-icons';
 
 export interface AvatarProps {
   /** Имя / @username — берём первый символ для placeholder. */
@@ -18,6 +19,11 @@ export interface AvatarProps {
   dotColor?: string;
   /** Класс для обёртки (position: relative кадр). */
   className?: string;
+  /**
+   * Saved Messages variant — blue circle with a bookmark glyph, Telegram-style.
+   * When set, `name`/`address` are ignored for the visual.
+   */
+  saved?: boolean;
 }
 
 /** Простое хэширование имени → один из 6 оттенков серого для разнообразия. */
@@ -28,10 +34,10 @@ function pickBg(seed: string): string {
   return shades[h % shades.length];
 }
 
-export function Avatar({ name, address, size = 48, dotColor, className }: AvatarProps) {
+export function Avatar({ name, address, size = 48, dotColor, className, saved }: AvatarProps) {
   const seed = (name ?? address ?? '?').replace(/^@/, '');
   const initial = seed.charAt(0).toUpperCase() || '?';
-  const bg = pickBg(seed);
+  const bg = saved ? '#1d9bf0' : pickBg(seed);
 
   return (
     <View className={className} style={{ width: size, height: size, position: 'relative' }}>
@@ -45,6 +51,9 @@ export function Avatar({ name, address, size = 48, dotColor, className }: Avatar
           justifyContent: 'center',
         }}
       >
+        {saved ? (
+          <Ionicons name="bookmark" size={size * 0.5} color="#ffffff" />
+        ) : (
           <Text
             style={{
               color: '#d0d0d0',
@@ -55,6 +64,7 @@ export function Avatar({ name, address, size = 48, dotColor, className }: Avatar
           >
             {initial}
           </Text>
+        )}
       </View>
       {dotColor && (
         <View

client-app/components/ChatTile.tsx

@@ -57,10 +57,12 @@ export interface ChatTileProps {
   contact:     Contact;
   lastMessage: Message | null;
   onPress:     () => void;
+  /** Render as the Saved Messages tile (blue bookmark avatar, fixed name). */
+  saved?:      boolean;
 }
 
-export function ChatTile({ contact: c, lastMessage, onPress }: ChatTileProps) {
-  const name = displayName(c);
+export function ChatTile({ contact: c, lastMessage, onPress, saved }: ChatTileProps) {
+  const name = saved ? 'Saved Messages' : displayName(c);
   const last = lastMessage;
 
   // Визуальный маркер типа чата.
@@ -92,7 +94,8 @@ export function ChatTile({ contact: c, lastMessage, onPress }: ChatTileProps) {
           name={name}
           address={c.address}
           size={44}
-          dotColor={c.x25519Pub && (!c.kind || c.kind === 'direct') ? '#3ba55d' : undefined}
+          saved={saved}
+          dotColor={!saved && c.x25519Pub && (!c.kind || c.kind === 'direct') ? '#3ba55d' : undefined}
         />
 
         <View style={{ flex: 1, marginLeft: 12, minWidth: 0 }}>
@@ -143,6 +146,8 @@ export function ChatTile({ contact: c, lastMessage, onPress }: ChatTileProps) {
             >
               {last
                 ? lastPreview(last)
+                : saved
+                  ? 'Your personal notes & files'
                   : c.x25519Pub
                     ? 'Tap to start encrypted chat'
                     : 'Waiting for identity…'}

client-app/components/SearchBar.tsx

@@ -1,12 +1,11 @@
 /**
- * SearchBar — серый блок, в состоянии idle текст с иконкой 🔍 отцентрированы.
- *
- * Когда пользователь тапает/фокусирует — поле становится input-friendly, но
- * визуально рестайл не нужен: при наличии текста placeholder скрыт и
- * пользовательский ввод выравнивается влево автоматически (multiline off).
+ * SearchBar — single-TextInput pill. Icon + input в одном ряду, без
+ * idle/focused двойного состояния (раньше был хак с невидимым
+ * TextInput поверх отцентрированного Text — ломал focus и выравнивание
+ * на Android).
  */
-import React, { useState } from 'react';
-import { View, TextInput, Text } from 'react-native';
+import React from 'react';
+import { View, TextInput, Pressable } from 'react-native';
 import { Ionicons } from '@expo/vector-icons';
 
 export interface SearchBarProps {
@@ -15,73 +14,55 @@ export interface SearchBarProps {
   placeholder?: string;
   autoFocus?: boolean;
   onSubmitEditing?: () => void;
+  onClear?: () => void;
 }
 
 export function SearchBar({
-  value, onChangeText, placeholder = 'Search', autoFocus, onSubmitEditing,
+  value, onChangeText, placeholder = 'Search', autoFocus, onSubmitEditing, onClear,
 }: SearchBarProps) {
-  const [focused, setFocused] = useState(false);
-
-  // Placeholder центрируется пока нет фокуса И нет значения.
-  // Как только юзер фокусируется или начинает печатать — иконка+текст
-  // прыгают к левому краю, чтобы не мешать вводу.
-  const centered = !focused && !value;
-
   return (
     <View
       style={{
-        backgroundColor: '#1a1a1a',
+        flexDirection: 'row',
+        alignItems: 'center',
+        backgroundColor: '#111111',
+        borderWidth: 1,
+        borderColor: '#1f1f1f',
         borderRadius: 999,
         paddingHorizontal: 14,
-        paddingVertical: 9,
-        minHeight: 36,
-        justifyContent: 'center',
+        gap: 8,
       }}
     >
-      {centered ? (
-        // ── Idle state — только текст+icon, отцентрированы.
-        // Невидимый TextInput поверх ловит tap, чтобы не дергать focus вручную.
-        <View style={{ flexDirection: 'row', alignItems: 'center', justifyContent: 'center' }}>
-          <Ionicons name="search" size={14} color="#8b8b8b" style={{ marginRight: 6 }} />
-          <Text style={{ color: '#8b8b8b', fontSize: 14 }}>{placeholder}</Text>
-          <TextInput
-            value={value}
-            onChangeText={onChangeText}
-            autoFocus={autoFocus}
-            onFocus={() => setFocused(true)}
-            onSubmitEditing={onSubmitEditing}
-            returnKeyType="search"
-            style={{
-              position: 'absolute', left: 0, right: 0, top: 0, bottom: 0,
-              color: 'transparent',
-              // Скрываем cursor в idle-режиме; при focus компонент перерисуется.
-            }}
-          />
-        </View>
-      ) : (
-        <View style={{ flexDirection: 'row', alignItems: 'center' }}>
-          <Ionicons name="search" size={14} color="#8b8b8b" style={{ marginRight: 8 }} />
+      <Ionicons name="search" size={16} color="#6a6a6a" />
       <TextInput
         value={value}
         onChangeText={onChangeText}
         placeholder={placeholder}
-            placeholderTextColor="#8b8b8b"
+        placeholderTextColor="#5a5a5a"
         autoCapitalize="none"
         autoCorrect={false}
-            autoFocus
-            onFocus={() => setFocused(true)}
-            onBlur={() => setFocused(false)}
+        autoFocus={autoFocus}
         onSubmitEditing={onSubmitEditing}
         returnKeyType="search"
         style={{
           flex: 1,
           color: '#ffffff',
           fontSize: 14,
+          paddingVertical: 10,
           padding: 0,
           includeFontPadding: false,
         }}
       />
-        </View>
+      {value.length > 0 && (
+        <Pressable
+          onPress={() => {
+            onChangeText('');
+            onClear?.();
+          }}
+          hitSlop={8}
+        >
+          <Ionicons name="close-circle" size={16} color="#6a6a6a" />
+        </Pressable>
       )}
     </View>
   );

client-app/components/chat/PostRefCard.tsx

@@ -90,7 +90,7 @@ export function PostRefCard({ postID, author, excerpt, hasImage, own }: PostRefC
             letterSpacing: 1.2,
           }}
         >
-          ПОСТ
+          POST
         </Text>
       </View>
 
@@ -132,7 +132,7 @@ export function PostRefCard({ postID, author, excerpt, hasImage, own }: PostRefC
             >
               <Ionicons name="image-outline" size={11} color={subColor} />
               <Text style={{ color: subColor, fontSize: 11 }}>
-                с фото
+                photo
               </Text>
             </View>
           )}

client-app/components/feed/PostCard.tsx

@@ -80,11 +80,16 @@ function PostCardInner({ post, likedByMe, onStatsChanged, onDeleted, compact }:
 
   // Find a display-friendly name for the author. If it's a known contact
   // with @username, use that; otherwise short-addr.
+  //
+  // `mine` takes precedence over the contact lookup: our own pub key has
+  // a self-contact entry with alias "Saved Messages" (that's how the
+  // self-chat tile is rendered), but that label is wrong in the feed —
+  // posts there should read as "You", not as a messaging-app affordance.
   const displayName = useMemo(() => {
+    if (mine) return 'You';
     const c = contacts.find(x => x.address === post.author);
     if (c?.username) return `@${c.username}`;
     if (c?.alias) return c.alias;
-    if (mine) return 'You';
     return shortAddr(post.author);
   }, [contacts, post.author, mine]);
 
@@ -109,7 +114,7 @@ function PostCardInner({ post, likedByMe, onStatsChanged, onDeleted, compact }:
       // Roll back optimistic update.
       setLocalLiked(wasLiked);
       setLocalLikeCount(c => c + (wasLiked ? 1 : -1));
-      Alert.alert('Не удалось', String(e?.message ?? e));
+      Alert.alert('Failed', String(e?.message ?? e));
     } finally {
       setBusy(false);
     }
@@ -128,13 +133,13 @@ function PostCardInner({ post, likedByMe, onStatsChanged, onDeleted, compact }:
     const options: Array<{ label: string; destructive?: boolean; onPress: () => void }> = [];
     if (mine) {
       options.push({
-        label: 'Удалить пост',
+        label: 'Delete post',
         destructive: true,
         onPress: () => {
-          Alert.alert('Удалить пост?', 'Это действие нельзя отменить.', [
-            { text: 'Отмена', style: 'cancel' },
+          Alert.alert('Delete post?', 'This action cannot be undone.', [
+            { text: 'Cancel', style: 'cancel' },
             {
-              text: 'Удалить',
+              text: 'Delete',
               style: 'destructive',
               onPress: async () => {
                 try {
@@ -145,7 +150,7 @@ function PostCardInner({ post, likedByMe, onStatsChanged, onDeleted, compact }:
                   });
                   onDeleted?.(post.post_id);
                 } catch (e: any) {
-                  Alert.alert('Ошибка', String(e?.message ?? e));
+                  Alert.alert('Error', String(e?.message ?? e));
                 }
               },
             },
@@ -160,9 +165,9 @@ function PostCardInner({ post, likedByMe, onStatsChanged, onDeleted, compact }:
         style: (o.destructive ? 'destructive' : 'default') as 'default' | 'destructive',
         onPress: o.onPress,
       })),
-      { text: 'Отмена', style: 'cancel' as const },
+      { text: 'Cancel', style: 'cancel' as const },
     ];
-    Alert.alert('Действия', '', buttons);
+    Alert.alert('Actions', '', buttons);
   }, [keyFile, mine, post.post_id, onDeleted]);
 
   // Attachment preview URL — native Image can stream straight from the

client-app/components/feed/ShareSheet.tsx

@@ -74,14 +74,14 @@ export function ShareSheet({ visible, post, onClose }: ShareSheetProps) {
         post, contacts: targets, keyFile,
       });
       if (failed > 0) {
-        Alert.alert('Готово', `Отправлено в ${ok} из ${ok + failed} чат${plural(ok + failed)}.`);
+        Alert.alert('Done', `Sent to ${ok} of ${ok + failed} ${plural(ok + failed)}.`);
       }
       // Close + reset regardless — done is done.
       setPicked(new Set());
       setQuery('');
       onClose();
     } catch (e: any) {
-      Alert.alert('Не удалось', String(e?.message ?? e));
+      Alert.alert('Failed', String(e?.message ?? e));
     } finally {
       setSending(false);
     }
@@ -136,7 +136,7 @@ export function ShareSheet({ visible, post, onClose }: ShareSheetProps) {
             paddingHorizontal: 16, marginBottom: 10,
           }}>
             <Text style={{ color: '#ffffff', fontSize: 17, fontWeight: '700' }}>
-              Поделиться постом
+              Share post
             </Text>
             <View style={{ flex: 1 }} />
             <Pressable onPress={closeAndReset} hitSlop={8}>
@@ -158,7 +158,7 @@ export function ShareSheet({ visible, post, onClose }: ShareSheetProps) {
               <TextInput
                 value={query}
                 onChangeText={setQuery}
-                placeholder="Поиск по контактам"
+                placeholder="Search contacts"
                 placeholderTextColor="#5a5a5a"
                 style={{
                   flex: 1,
@@ -196,8 +196,8 @@ export function ShareSheet({ visible, post, onClose }: ShareSheetProps) {
                 <Ionicons name="people-outline" size={28} color="#5a5a5a" />
                 <Text style={{ color: '#8b8b8b', fontSize: 13, marginTop: 10 }}>
                   {query.length > 0
-                    ? 'Нет контактов по такому запросу'
-                    : 'Контакты с ключами шифрования отсутствуют'}
+                    ? 'No contacts match this search'
+                    : 'No contacts with encryption keys yet'}
                 </Text>
               </View>
             }
@@ -227,8 +227,8 @@ export function ShareSheet({ visible, post, onClose }: ShareSheetProps) {
                   fontSize: 14,
                 }}>
                   {picked.size === 0
-                    ? 'Выберите контакты'
-                    : `Отправить (${picked.size})`}
+                    ? 'Select contacts'
+                    : `Send (${picked.size})`}
                 </Text>
               )}
             </Pressable>
@@ -298,10 +298,5 @@ function shortAddr(a: string, n = 6): string {
 }
 
 function plural(n: number): string {
-  const mod100 = n % 100;
-  const mod10  = n % 10;
-  if (mod100 >= 11 && mod100 <= 19) return 'ов';
-  if (mod10 === 1) return '';
-  if (mod10 >= 2 && mod10 <= 4) return 'а';
-  return 'ов';
+  return n === 1 ? 'chat' : 'chats';
 }

client-app/lib/api.ts

@@ -79,23 +79,23 @@ async function post<T>(path: string, body: unknown): Promise<T> {
 export function humanizeTxError(e: unknown): string {
   const raw = e instanceof Error ? e.message : String(e);
   if (raw.startsWith('429')) {
-    return 'Слишком много запросов к ноде. Подождите пару секунд и попробуйте снова.';
+    return 'Too many requests to the node. Wait a couple of seconds and try again.';
   }
   if (raw.startsWith('400') && raw.includes('timestamp')) {
-    return 'Часы устройства не синхронизированы с нодой. Проверьте время на телефоне (±1 час).';
+    return 'Device clock is out of sync with the node. Check the time on your phone (±1 hour).';
   }
   if (raw.startsWith('400') && raw.includes('signature')) {
-    return 'Подпись транзакции невалидна. Попробуйте ещё раз; если не помогает — вероятна несовместимость версий клиента и ноды.';
+    return 'Transaction signature is invalid. Try again; if this persists the client and node versions may be incompatible.';
   }
   if (raw.startsWith('400')) {
-    return `Нода отклонила транзакцию: ${raw.replace(/^400:\s*/, '')}`;
+    return `Node rejected transaction: ${raw.replace(/^400:\s*/, '')}`;
   }
   if (raw.startsWith('5')) {
-    return `Ошибка ноды (${raw}). Попробуйте позже.`;
+    return `Node error (${raw}). Please try again later.`;
   }
   // Network-level
   if (raw.toLowerCase().includes('network request failed')) {
-    return 'Нет связи с нодой. Проверьте URL в настройках и доступность сервера.';
+    return 'Cannot reach the node. Check the URL in settings and that the server is online.';
   }
   return raw;
 }
@@ -191,6 +191,43 @@ export async function submitTx(tx: RawTx): Promise<{ id: string; status: string
   }
 }
 
+/**
+ * Full transaction detail as returned by GET /api/tx/{id}. Matches the
+ * explorer's txDetail wire format. Payload is JSON-decoded when the
+ * node recognises the tx type, otherwise payload_hex is set.
+ */
+export interface TxDetail {
+  id:             string;
+  type:           string;
+  memo?:          string;
+  from:           string;
+  from_addr?:     string;
+  to?:            string;
+  to_addr?:       string;
+  amount_ut:      number;
+  amount:         string;
+  fee_ut:         number;
+  fee:            string;
+  time:           string;         // ISO-8601 UTC
+  block_index:    number;
+  block_hash:     string;
+  block_time:     string;         // ISO-8601 UTC
+  gas_used?:      number;
+  payload?:       unknown;
+  payload_hex?:   string;
+  signature_hex?: string;
+}
+
+/** Fetch full tx detail by hash/id. Returns null on 404. */
+export async function getTxDetail(txID: string): Promise<TxDetail | null> {
+  try {
+    return await get<TxDetail>(`/api/tx/${txID}`);
+  } catch (e: any) {
+    if (/→\s*404\b/.test(String(e?.message))) return null;
+    throw e;
+  }
+}
+
 export async function getTxHistory(pubkey: string, limit = 50): Promise<TxRecord[]> {
   const data = await get<AddrResponse>(`/api/address/${pubkey}?limit=${limit}`);
   return (data.transactions ?? []).map(tx => ({
@@ -302,7 +339,7 @@ export async function fetchInbox(x25519PubHex: string): Promise<Envelope[]> {
 // ─── Contact requests (on-chain) ─────────────────────────────────────────────
 
 /**
- * Maps blockchain.ContactInfo returned by GET /api/relay/contacts?pub=...
+ * Maps blockchain.ContactInfo returned by GET /relay/contacts?pub=...
  * The response shape is { pub, count, contacts: ContactInfo[] }.
  */
 export interface ContactRequestRaw {
@@ -316,7 +353,7 @@ export interface ContactRequestRaw {
 }
 
 export async function fetchContactRequests(edPubHex: string): Promise<ContactRequestRaw[]> {
-  const data = await get<{ contacts: ContactRequestRaw[] }>(`/api/relay/contacts?pub=${edPubHex}`);
+  const data = await get<{ contacts: ContactRequestRaw[] }>(`/relay/contacts?pub=${edPubHex}`);
   return data.contacts ?? [];
 }
 
@@ -328,6 +365,58 @@ export interface IdentityInfo {
   x25519_pub: string;   // hex Curve25519 key; empty string if not published
   nickname:   string;
   registered: boolean;
+  /**
+   * Number of active (non-revoked) devices linked to this master identity
+   * via LINK_DEVICE (v2.2.0). 0 for legacy identities that only published
+   * a single X25519 via REGISTER_KEY — senders should fall back to
+   * `x25519_pub` above and skip the device fan-out path.
+   */
+  device_count?: number;
+}
+
+/**
+ * One active device in an identity's multi-device registry. Returned by
+ * GET /api/devices/{master_pub} as part of `devices[]`. Senders use the
+ * list to fan out one sealed envelope per X25519 pub so all of the
+ * recipient's devices receive the message.
+ */
+export interface DeviceInfo {
+  x25519_pub_key: string;
+  device_name:    string;
+  added_at:       number;  // unix seconds
+}
+
+/**
+ * Relay registration info for a node pub key, as returned by
+ * /api/relays (which comes back as an array of RegisteredRelayInfo).
+ * We don't wrap the individual lookup on the server — just filter the
+ * full list client-side. It's bounded (N nodes in the network) and
+ * cached heavily enough that this is cheaper than a new endpoint.
+ */
+export interface RegisteredRelayInfo {
+  pub_key:         string;
+  address:         string;
+  relay: {
+    x25519_pub_key: string;
+    fee_per_msg_ut: number;
+    multiaddr?:     string;
+  };
+  last_heartbeat?: number;  // unix seconds
+}
+
+/** GET /api/relays — all relay nodes registered on-chain. */
+export async function getRelays(): Promise<RegisteredRelayInfo[]> {
+  try {
+    return await get<RegisteredRelayInfo[]>('/api/relays');
+  } catch {
+    return [];
+  }
+}
+
+/** Find relay entry for a specific pub key. null if the address isn't a relay. */
+export async function getRelayFor(pubKey: string): Promise<RegisteredRelayInfo | null> {
+  const all = await getRelays();
+  return all.find(r => r.pub_key === pubKey) ?? null;
 }
 
 /** Fetch identity info for any pubkey or DC address. Returns null on 404. */
@@ -339,6 +428,56 @@ export async function getIdentity(pubkeyOrAddr: string): Promise<IdentityInfo |
   }
 }
 
+// ─── Multi-device registry (v2.2.0) ───────────────────────────────────────
+
+interface DevicesResponse {
+  master_pub: string;
+  count:      number;
+  devices:    DeviceInfo[];
+}
+
+/**
+ * GET /api/devices/{master_pub} — all active (non-revoked) device records
+ * for the given master identity. Returns an empty array for a legacy
+ * identity (device_count == 0) or a network error — callers should treat
+ * both the same way and fall back to IdentityInfo.x25519_pub so the
+ * pre-v2.2.0 single-device path keeps working.
+ */
+export async function fetchDevices(masterPub: string): Promise<DeviceInfo[]> {
+  try {
+    const resp = await get<DevicesResponse>(`/api/devices/${masterPub}`);
+    return resp.devices ?? [];
+  } catch {
+    return [];
+  }
+}
+
+/**
+ * Pick the right set of recipient X25519 pubs for a sender's fan-out.
+ * Two paths, in priority order:
+ *
+ *   1. New path — /api/devices returns ≥1 entry. Send to each device.
+ *   2. Legacy path — identity published an X25519 via REGISTER_KEY
+ *      (pre-v2.2.0 clients). Send to just that one.
+ *
+ * Returns an empty array only when the recipient has published nothing
+ * at all — caller must surface "no encryption key" to the user rather
+ * than drop the message on the floor.
+ */
+export async function resolveRecipientKeys(
+  recipientMasterPub: string,
+): Promise<string[]> {
+  const devs = await fetchDevices(recipientMasterPub);
+  if (devs.length > 0) {
+    return devs.map(d => d.x25519_pub_key);
+  }
+  const identity = await getIdentity(recipientMasterPub);
+  if (identity?.x25519_pub) {
+    return [identity.x25519_pub];
+  }
+  return [];
+}
+
 // ─── Contract API ─────────────────────────────────────────────────────────────
 
 /**
@@ -642,6 +781,68 @@ export function buildTransferTx(params: {
   };
 }
 
+/**
+ * LINK_DEVICE transaction — publish a per-device X25519 pub in the
+ * identity's device registry so senders can fan out envelopes across
+ * every active device. Signed by the master Ed25519 (= `from`).
+ *
+ * `deviceName` is a short human label shown in Settings → Devices
+ * (≤ 64 bytes, printable ASCII/UTF-8, no control chars).
+ */
+export function buildLinkDeviceTx(params: {
+  from:        string;  // master Ed25519 pubkey
+  x25519Pub:   string;  // per-device X25519 pubkey (64 hex chars, lowercase)
+  deviceName:  string;
+  privKey:     string;
+}): RawTx {
+  const id        = newTxID();
+  const timestamp = rfc3339Now();
+  const payloadObj = {
+    x25519_pub_key: params.x25519Pub,
+    device_name:    params.deviceName,
+  };
+  const payload = strToBase64(JSON.stringify(payloadObj));
+
+  const canonical = txCanonicalBytes({
+    id, type: 'LINK_DEVICE', from: params.from, to: '',
+    amount: 0, fee: MIN_TX_FEE, payload, timestamp,
+  });
+
+  return {
+    id, type: 'LINK_DEVICE', from: params.from, to: '',
+    amount: 0, fee: MIN_TX_FEE, payload, timestamp,
+    signature: signBase64(canonical, params.privKey),
+  };
+}
+
+/**
+ * UNLINK_DEVICE transaction — revoke a previously-linked device so senders
+ * stop shipping envelopes to its X25519 pub. The revoked device itself,
+ * when it next comes online and sees its own pub in the revoked list,
+ * is expected to wipe local state (master priv + cached chats).
+ */
+export function buildUnlinkDeviceTx(params: {
+  from:       string;   // master Ed25519 pubkey
+  x25519Pub:  string;   // pub to revoke
+  privKey:    string;
+}): RawTx {
+  const id        = newTxID();
+  const timestamp = rfc3339Now();
+  const payloadObj = { x25519_pub_key: params.x25519Pub };
+  const payload = strToBase64(JSON.stringify(payloadObj));
+
+  const canonical = txCanonicalBytes({
+    id, type: 'UNLINK_DEVICE', from: params.from, to: '',
+    amount: 0, fee: MIN_TX_FEE, payload, timestamp,
+  });
+
+  return {
+    id, type: 'UNLINK_DEVICE', from: params.from, to: '',
+    amount: 0, fee: MIN_TX_FEE, payload, timestamp,
+    signature: signBase64(canonical, params.privKey),
+  };
+}
+
 /**
  * CONTACT_REQUEST transaction.
  *

client-app/lib/dates.ts

@@ -5,10 +5,10 @@
  * который тоже в секундах). Для ms-таймштампов делаем нормализацию внутри.
  */
 
-// ─── Русские месяцы (genitive для "17 июня 2025") ────────────────────────────
-const RU_MONTHS_GEN = [
-  'января', 'февраля', 'марта',  'апреля', 'мая',     'июня',
-  'июля',   'августа', 'сентября', 'октября', 'ноября', 'декабря',
+// English short month names ("Jun 17, 2025").
+const MONTHS_SHORT = [
+  'Jan', 'Feb', 'Mar', 'Apr', 'May', 'Jun',
+  'Jul', 'Aug', 'Sep', 'Oct', 'Nov', 'Dec',
 ];
 
 function sameDay(a: Date, b: Date): boolean {
@@ -20,8 +20,8 @@ function sameDay(a: Date, b: Date): boolean {
 }
 
 /**
- * Day-bucket label для сепараторов внутри чата.
- *   "Сегодня" / "Вчера" / "17 июня 2025"
+ * Day-bucket label for chat separators.
+ *   "Today" / "Yesterday" / "Jun 17, 2025"
  *
  * @param ts unix-seconds
  */
@@ -29,9 +29,9 @@ export function dateBucket(ts: number): string {
   const d = new Date(ts * 1000);
   const now = new Date();
   const yday = new Date(); yday.setDate(now.getDate() - 1);
-  if (sameDay(d, now))  return 'Сегодня';
-  if (sameDay(d, yday)) return 'Вчера';
-  return `${d.getDate()} ${RU_MONTHS_GEN[d.getMonth()]} ${d.getFullYear()}`;
+  if (sameDay(d, now))  return 'Today';
+  if (sameDay(d, yday)) return 'Yesterday';
+  return `${MONTHS_SHORT[d.getMonth()]} ${d.getDate()}, ${d.getFullYear()}`;
 }
 
 /**

client-app/lib/devSeed.ts

@@ -1,444 +0,0 @@
-/**
- * Dev seed — заполняет store фейковыми контактами и сообщениями для UI-теста.
- *
- * Запускается один раз при монтировании layout'а если store пустой
- * (useDevSeed). Реальные контакты через WS/HTTP приходят позже —
- * `upsertContact` перезаписывает mock'и по address'у.
- *
- * Цели seed'а:
- *   1. Показать все три типа чатов (direct / group / channel) с разным
- *      поведением sender-meta.
- *   2. Наполнить список чатов до скролла (15+ контактов).
- *   3. В каждом чате — ≥15 сообщений для скролла в chat view.
- *   4. Продемонстрировать "staircase" (run'ы одного отправителя
- *      внутри 1h-окна) и переключения между отправителями.
- */
-import { useEffect } from 'react';
-import { useStore } from './store';
-import type { Contact, Message } from './types';
-
-// ─── Детерминированные «pubkey» (64 hex символа) ───────────────────
-function fakeHex(seed: number): string {
-  let h = '';
-  let x = seed;
-  for (let i = 0; i < 32; i++) {
-    x = (x * 1103515245 + 12345) & 0xffffffff;
-    h += (x & 0xff).toString(16).padStart(2, '0');
-  }
-  return h;
-}
-
-const now = () => Math.floor(Date.now() / 1000);
-const MINE = fakeHex(9999);
-
-// ─── Контакты ──────────────────────────────────────────────────────
-// 16 штук: 5 DM + 6 групп + 5 каналов. Поле `addedAt` задаёт порядок в
-// списке когда нет messages — ordering-fallback.
-
-const mockContacts: Contact[] = [
-  // ── DM ──────────────────────────────────────────────────────────
-  { address: fakeHex(1001), x25519Pub: fakeHex(2001),
-    username: 'jordan', addedAt: Date.now() - 60 * 60 * 1_000, kind: 'direct' },
-  { address: fakeHex(1002), x25519Pub: fakeHex(2002),
-    alias: 'Myles Wagner', addedAt: Date.now() - 2 * 60 * 60 * 1_000, kind: 'direct' },
-  { address: fakeHex(1010), x25519Pub: fakeHex(2010),
-    username: 'sarah_k', addedAt: Date.now() - 3 * 60 * 60 * 1_000, kind: 'direct',
-    unread: 2 },
-  { address: fakeHex(1011), x25519Pub: fakeHex(2011),
-    alias: 'Mom',       addedAt: Date.now() - 5 * 60 * 60 * 1_000, kind: 'direct' },
-  { address: fakeHex(1012), x25519Pub: fakeHex(2012),
-    username: 'alex_dev', addedAt: Date.now() - 6 * 60 * 60 * 1_000, kind: 'direct' },
-
-  // ── Groups ─────────────────────────────────────────────────────
-  { address: fakeHex(1003), x25519Pub: fakeHex(2003),
-    alias: 'Tahoe weekend 🌲', addedAt: Date.now() - 4 * 60 * 60 * 1_000, kind: 'group' },
-  { address: fakeHex(1004), x25519Pub: fakeHex(2004),
-    alias: 'Knicks tickets', addedAt: Date.now() - 5 * 60 * 60 * 1_000, kind: 'group',
-    unread: 3 },
-  { address: fakeHex(1020), x25519Pub: fakeHex(2020),
-    alias: 'Family',   addedAt: Date.now() - 8 * 60 * 60 * 1_000, kind: 'group' },
-  { address: fakeHex(1021), x25519Pub: fakeHex(2021),
-    alias: 'Work eng',  addedAt: Date.now() - 12 * 60 * 60 * 1_000, kind: 'group',
-    unread: 7 },
-  { address: fakeHex(1022), x25519Pub: fakeHex(2022),
-    alias: 'Book club', addedAt: Date.now() - 24 * 60 * 60 * 1_000, kind: 'group' },
-  { address: fakeHex(1023), x25519Pub: fakeHex(2023),
-    alias: 'Tuesday D&D 🎲', addedAt: Date.now() - 30 * 60 * 60 * 1_000, kind: 'group' },
-
-  // (Channel seeds removed in v2.0.0 — channels replaced by the social feed.)
-];
-
-// ─── Генератор сообщений ───────────────────────────────────────────
-
-// Альт-отправители для group-чатов — нужны только как идентификатор `from`.
-const P_TYRA  = fakeHex(3001);
-const P_MYLES = fakeHex(3002);
-const P_NATE  = fakeHex(3003);
-const P_TYLER = fakeHex(3004);
-const P_MOM   = fakeHex(3005);
-const P_DAD   = fakeHex(3006);
-const P_SIS   = fakeHex(3007);
-const P_LEAD  = fakeHex(3008);
-const P_PM    = fakeHex(3009);
-const P_QA    = fakeHex(3010);
-const P_DESIGN= fakeHex(3011);
-const P_ANNA  = fakeHex(3012);
-const P_DM_PEER = fakeHex(3013);
-
-type Msg = Omit<Message, 'id'>;
-
-function list(prefix: string, list: Msg[]): Message[] {
-  return list.map((m, i) => ({ ...m, id: `${prefix}_${i}` }));
-}
-
-function mockMessagesFor(contact: Contact): Message[] {
-  const peer = contact.x25519Pub;
-
-  // ── DM: @jordan ────────────────────────────────────────────────
-  if (contact.username === 'jordan') {
-    // Важно: id'ы сообщений используются в replyTo.id, поэтому
-    // указываем их явно где нужно сшить thread.
-    const msgs: Message[] = list('jordan', [
-      { from: peer, mine: false, timestamp: now() - 60 * 60 * 22, text: 'Hey, have a sec later today?' },
-      { from: MINE, mine: true,  timestamp: now() - 60 * 60 * 21, read: true, text: 'yep around 4pm' },
-      { from: peer, mine: false, timestamp: now() - 60 * 60 * 20, text: 'cool, coffee at the corner spot?' },
-      { from: MINE, mine: true,  timestamp: now() - 60 * 60 * 19, read: true, text: 'works' },
-      { from: peer, mine: false, timestamp: now() - 60 * 60 * 4,  text: 'just parked 🚗' },
-      { from: peer, mine: false, timestamp: now() - 60 * 60 * 4,  text: 'see you in 5' },
-      { from: MINE, mine: true,  timestamp: now() - 60 * 60 * 3,  read: true, text: "that was a great catchup" },
-      { from: peer, mine: false, timestamp: now() - 60 * 60 * 3,  text: "totally — thanks for the book rec" },
-      { from: peer, mine: false, timestamp: now() - 60 * 40, text: 'Hey Jordan - Got tickets to the Knicks game tomorrow, let me know if you want to come!' },
-      { from: peer, mine: false, timestamp: now() - 60 * 39, text: "we've got floor seats 🔥" },
-      { from: peer, mine: false, timestamp: now() - 60 * 38, text: "starts at 7, pregame at the bar across the street" },
-      { from: MINE, mine: true,  timestamp: now() - 60 * 14, read: true, edited: true, text: 'Ah sadly I already have plans' },
-      { from: MINE, mine: true,  timestamp: now() - 60 * 13, read: true, text: 'maybe next time?' },
-      { from: peer, mine: false, timestamp: now() - 60 * 5,  text: "no worries — enjoy whatever you're up to" },
-      { from: peer, mine: false, timestamp: now() - 60 * 2,  text: "wish you could make it tho 🏀" },
-    ]);
-    // Пришьём reply: MINE-сообщение "Ah sadly…" отвечает на "Hey Jordan - Got tickets…"
-    const target = msgs.find(m => m.text.startsWith('Hey Jordan - Got tickets'));
-    const mine   = msgs.find(m => m.text === 'Ah sadly I already have plans');
-    if (target && mine) {
-      mine.replyTo = {
-        id:     target.id,
-        author: '@jordan',
-        text:   target.text,
-      };
-    }
-    return msgs;
-  }
-
-  // ── DM: Myles Wagner ───────────────────────────────────────────
-  if (contact.alias === 'Myles Wagner') {
-    return list('myles', [
-      { from: peer, mine: false, timestamp: now() - 60 * 60 * 30, text: 'saw the draft, left a bunch of comments' },
-      { from: MINE, mine: true,  timestamp: now() - 60 * 60 * 29, read: true, text: 'thx, going through them now' },
-      { from: peer, mine: false, timestamp: now() - 60 * 60 * 29, text: 'no rush — tomorrow is fine' },
-      { from: peer, mine: false, timestamp: now() - 60 * 60 * 5, text: 'lunch today?' },
-      { from: MINE, mine: true,  timestamp: now() - 60 * 60 * 4, read: true, text: "can't, stuck in reviews" },
-      { from: MINE, mine: true,  timestamp: now() - 60 * 60 * 4, read: true, text: 'tomorrow?' },
-      { from: peer, mine: false, timestamp: now() - 60 * 60 * 4, text: '✅ tomorrow' },
-      {
-        from: peer, mine: false, timestamp: now() - 60 * 60 * 2, text: '',
-        attachment: {
-          kind: 'voice',
-          uri:  'voice-demo://myles-1',
-          duration: 17,
-        },
-      },
-      { from: peer, mine: false, timestamp: now() - 60 * 25, text: 'the dchain repo finally built for me' },
-      { from: peer, mine: false, timestamp: now() - 60 * 25, text: 'docker weirdness was the issue' },
-      { from: MINE, mine: true,  timestamp: now() - 60 * 21, read: true, text: "nice, told you the WSL path would do it" },
-      { from: peer, mine: false, timestamp: now() - 60 * 20, text: 'So good!' },
-    ]);
-  }
-
-  // ── DM: @sarah_k (с unread=2) ──────────────────────────────────
-  if (contact.username === 'sarah_k') {
-    return list('sarah', [
-      { from: peer, mine: false, timestamp: now() - 60 * 60 * 30, text: "hey! been a while" },
-      { from: MINE, mine: true,  timestamp: now() - 60 * 60 * 28, read: true, text: 'yeah, finally surfaced after the launch crunch' },
-      { from: peer, mine: false, timestamp: now() - 60 * 60 * 27, text: 'how did it go?' },
-      { from: MINE, mine: true,  timestamp: now() - 60 * 60 * 27, read: true, text: "pretty well actually 🙏" },
-      { from: peer, mine: false, timestamp: now() - 60 * 60 * 2, text: 'btw drinks on friday?' },
-      { from: peer, mine: false, timestamp: now() - 60 * 60 * 2, text: 'that new wine bar' },
-      { from: peer, mine: false, timestamp: now() - 60 * 60 * 2, text: 'around 7 if you can make it' },
-    ]);
-  }
-
-  // ── DM: Mom ────────────────────────────────────────────────────
-  if (contact.alias === 'Mom') {
-    return list('mom', [
-      { from: peer, mine: false, timestamp: now() - 60 * 60 * 48, text: 'Did you see the photos from the trip?' },
-      { from: MINE, mine: true,  timestamp: now() - 60 * 60 * 47, read: true, text: 'not yet, send them again?' },
-      { from: peer, mine: false, timestamp: now() - 60 * 60 * 47, text: 'ok' },
-      {
-        from: peer, mine: false, timestamp: now() - 60 * 60 * 46, text: '',
-        attachment: {
-          kind:   'image',
-          uri:    'https://images.unsplash.com/photo-1506905925346-21bda4d32df4?w=800',
-          width:  800, height: 533, mime: 'image/jpeg',
-        },
-      },
-      {
-        from: peer, mine: false, timestamp: now() - 60 * 60 * 46, text: '',
-        attachment: {
-          kind:   'image',
-          uri:    'https://images.unsplash.com/photo-1519681393784-d120267933ba?w=800',
-          width:  800, height: 533, mime: 'image/jpeg',
-        },
-      },
-      { from: MINE, mine: true,  timestamp: now() - 60 * 60 * 30, read: true, text: 'wow, grandma looks great' },
-      { from: peer, mine: false, timestamp: now() - 60 * 60 * 30, text: 'she asked about you!' },
-      { from: peer, mine: false, timestamp: now() - 60 * 60 * 7, text: 'call later?' },
-    ]);
-  }
-
-  // ── DM: @alex_dev ──────────────────────────────────────────────
-  if (contact.username === 'alex_dev') {
-    return list('alex', [
-      { from: peer, mine: false, timestamp: now() - 60 * 60 * 12, text: 'did you try the new WASM build?' },
-      { from: MINE, mine: true,  timestamp: now() - 60 * 60 * 11, read: true, text: 'yeah, loader error on start' },
-      { from: peer, mine: false, timestamp: now() - 60 * 60 * 11, text: 'path encoding issue again?' },
-      { from: MINE, mine: true,  timestamp: now() - 60 * 60 * 10, read: true, text: 'probably, checking now' },
-      { from: MINE, mine: true,  timestamp: now() - 60 * 60 * 8, read: true, text: 'yep, was the trailing slash' },
-      { from: peer, mine: false, timestamp: now() - 60 * 60 * 8, text: 'classic 😅' },
-      { from: peer, mine: false, timestamp: now() - 60 * 60 * 7, text: 'PR for that incoming tomorrow' },
-    ]);
-  }
-
-  // ── Group: Tahoe weekend 🌲 ────────────────────────────────────
-  if (contact.alias === 'Tahoe weekend 🌲') {
-    const msgs: Message[] = list('tahoe', [
-      { from: P_TYRA,  mine: false, timestamp: now() - 60 * 60 * 50, text: "who's in for Tahoe this weekend?" },
-      { from: P_MYLES, mine: false, timestamp: now() - 60 * 60 * 49, text: "me!" },
-      { from: MINE,    mine: true,  timestamp: now() - 60 * 60 * 48, read: true, text: "count me in" },
-      { from: P_TYRA,  mine: false, timestamp: now() - 60 * 60 * 48, text: "woohoo 🎉" },
-      { from: P_ANNA,  mine: false, timestamp: now() - 60 * 60 * 47, text: "planning friday night → sunday evening yeah?" },
-      { from: P_TYRA,  mine: false, timestamp: now() - 60 * 60 * 46, text: "yep, maybe leave friday after lunch" },
-      { from: P_MYLES, mine: false, timestamp: now() - 60 * 60 * 30, text: "I made this itinerary with Grok, what do you think?" },
-      { from: P_MYLES, mine: false, timestamp: now() - 60 * 60 * 30, text: "Day 1: Eagle Falls hike" },
-      { from: P_MYLES, mine: false, timestamp: now() - 60 * 60 * 30, text: "Day 2: Emerald bay kayak" },
-      { from: P_MYLES, mine: false, timestamp: now() - 60 * 60 * 30, text: "Day 3: lazy breakfast then drive back" },
-      {
-        from: P_MYLES, mine: false, timestamp: now() - 60 * 60 * 30, text: '',
-        attachment: {
-          kind: 'file',
-          uri:  'https://example.com/Lake_Tahoe_Itinerary.pdf',
-          name: 'Lake_Tahoe_Itinerary.pdf',
-          size: 97_280, // ~95 KB
-          mime: 'application/pdf',
-        },
-      },
-      { from: MINE,    mine: true,  timestamp: now() - 60 * 60 * 24, read: true, edited: true, text: "Love it — Eagle falls looks insane" },
-      { from: P_ANNA,  mine: false, timestamp: now() - 60 * 60 * 24, text: "Eagle falls was stunning last year!" },
-      { from: P_TYRA,  mine: false, timestamp: now() - 60 * 31, text: "who's excited for Tahoe this weekend?" },
-      { from: P_TYRA,  mine: false, timestamp: now() - 60 * 30, text: "I've been checking the forecast — sun all weekend 🌞" },
-      { from: P_MYLES, mine: false, timestamp: now() - 60 * 22, text: "I made this itinerary with Grok, what do you think?" },
-      { from: P_MYLES, mine: false, timestamp: now() - 60 * 21, text: "Day 1 we can hit Eagle Falls" },
-      { from: MINE,    mine: true,  timestamp: now() - 60 * 14, read: true, edited: true, text: "Love it — Eagle falls looks insane" },
-      {
-        from: P_TYRA, mine: false, timestamp: now() - 60 * 3, text: 'pic from my last trip 😍',
-        attachment: {
-          kind:   'image',
-          uri:    'https://images.unsplash.com/photo-1505245208761-ba872912fac0?w=800',
-          width:  800,
-          height: 1000,
-          mime:   'image/jpeg',
-        },
-      },
-    ]);
-    // Thread: mine "Love it — Eagle falls looks insane" — ответ на
-    // Myles'овский itinerary-PDF. Берём ПЕРВЫЙ match "Day 1 we can hit
-    // Eagle Falls" и пришиваем его к первому mine-bubble'у.
-    const target = msgs.find(m => m.text === 'Day 1 we can hit Eagle Falls');
-    const reply  = msgs.find(m => m.text === 'Love it — Eagle falls looks insane' && m.mine);
-    if (target && reply) {
-      reply.replyTo = {
-        id:     target.id,
-        author: 'Myles Wagner',
-        text:   target.text,
-      };
-    }
-    return msgs;
-  }
-
-  // ── Group: Knicks tickets ──────────────────────────────────────
-  if (contact.alias === 'Knicks tickets') {
-    return list('knicks', [
-      { from: P_NATE,  mine: false, timestamp: now() - 60 * 60 * 20, text: "quick group update — got 5 tickets for thursday" },
-      { from: P_TYLER, mine: false, timestamp: now() - 60 * 60 * 19, text: 'wow nice' },
-      { from: P_TYLER, mine: false, timestamp: now() - 60 * 60 * 19, text: 'where are we seated?' },
-      { from: P_NATE,  mine: false, timestamp: now() - 60 * 60 * 19, text: 'section 102, row 12' },
-      { from: MINE,    mine: true,  timestamp: now() - 60 * 60 * 18, read: true, text: 'thats a great spot' },
-      { from: P_ANNA,  mine: false, timestamp: now() - 60 * 60 * 18, text: "can someone venmo nate 🙏" },
-      { from: MINE,    mine: true,  timestamp: now() - 60 * 60 * 17, read: true, text: 'sending now' },
-      { from: P_NATE,  mine: false, timestamp: now() - 60 * 32, text: "Ok who's in for tomorrow's game?" },
-      { from: P_NATE,  mine: false, timestamp: now() - 60 * 31, text: 'Got 2 extra tickets, first-come-first-served' },
-      { from: P_TYLER, mine: false, timestamp: now() - 60 * 27, text: "I'm in!" },
-      { from: P_TYLER, mine: false, timestamp: now() - 60 * 26, text: 'What time does it start?' },
-      { from: MINE,    mine: true,  timestamp: now() - 60 * 20, read: true, text: "Let's meet at the bar around 6?" },
-      { from: P_NATE,  mine: false, timestamp: now() - 60 * 15, text: 'Sounds good' },
-    ]);
-  }
-
-  // ── Group: Family ──────────────────────────────────────────────
-  if (contact.alias === 'Family') {
-    return list('family', [
-      { from: P_MOM, mine: false, timestamp: now() - 60 * 60 * 36, text: 'remember grandma birthday on sunday' },
-      { from: P_DAD, mine: false, timestamp: now() - 60 * 60 * 36, text: 'noted 🎂' },
-      { from: P_SIS, mine: false, timestamp: now() - 60 * 60 * 35, text: 'who is bringing the cake?' },
-      { from: P_MOM, mine: false, timestamp: now() - 60 * 60 * 35, text: "I'll get it from the bakery" },
-      { from: MINE,  mine: true,  timestamp: now() - 60 * 60 * 34, read: true, text: 'I can pick up flowers' },
-      { from: P_SIS, mine: false, timestamp: now() - 60 * 60 * 34, text: 'perfect' },
-      { from: P_DAD, mine: false, timestamp: now() - 60 * 60 * 8, text: 'forecast is rain sunday — backup plan?' },
-      { from: P_MOM, mine: false, timestamp: now() - 60 * 60 * 8, text: "we'll move indoors, the living room works" },
-      { from: P_SIS, mine: false, timestamp: now() - 60 * 60 * 7, text: 'works!' },
-    ]);
-  }
-
-  // ── Group: Work eng (unread=7) ─────────────────────────────────
-  if (contact.alias === 'Work eng') {
-    return list('work', [
-      { from: P_LEAD, mine: false, timestamp: now() - 60 * 60 * 16, text: 'standup at 10 moved to 11 today btw' },
-      { from: P_PM,   mine: false, timestamp: now() - 60 * 60 * 16, text: 'thanks!' },
-      { from: P_QA,   mine: false, timestamp: now() - 60 * 60 * 15, text: "the staging deploy broke again 🙃" },
-      { from: P_LEAD, mine: false, timestamp: now() - 60 * 60 * 15, text: "ugh, looking" },
-      { from: P_LEAD, mine: false, timestamp: now() - 60 * 60 * 14, text: 'fixed — migration was stuck' },
-      { from: MINE,   mine: true,  timestamp: now() - 60 * 60 * 13, read: true, text: 'Worked for me now 👍' },
-      { from: P_PM,   mine: false, timestamp: now() - 60 * 60 * 5, text: 'reminder: demo tomorrow, slides by eod' },
-      { from: P_LEAD, mine: false, timestamp: now() - 60 * 60 * 4, text: 'Ill handle the technical half' },
-      { from: P_DESIGN,mine: false,timestamp: now() - 60 * 60 * 4, text: 'just posted the v2 mocks in figma' },
-      { from: P_PM,   mine: false, timestamp: now() - 60 * 60 * 3, text: 'chatting with sales — 3 new trials this week' },
-      { from: P_QA,   mine: false, timestamp: now() - 60 * 60 * 2, text: 'flaky test on CI — investigating' },
-      { from: P_LEAD, mine: false, timestamp: now() - 60 * 30, text: 'okay seems like CI is green now' },
-      { from: P_LEAD, mine: false, timestamp: now() - 60 * 28, text: 'retry passed' },
-      { from: P_PM,   mine: false, timestamp: now() - 60 * 20, text: "we're good for release" },
-    ]);
-  }
-
-  // ── Group: Book club ───────────────────────────────────────────
-  if (contact.alias === 'Book club') {
-    return list('book', [
-      { from: P_ANNA,  mine: false, timestamp: now() - 60 * 60 * 96, text: 'next month: "Project Hail Mary"?' },
-      { from: MINE,    mine: true,  timestamp: now() - 60 * 60 * 95, read: true, text: '👍' },
-      { from: P_SIS,   mine: false, timestamp: now() - 60 * 60 * 94, text: 'yes please' },
-      { from: P_TYRA,  mine: false, timestamp: now() - 60 * 60 * 48, text: 'halfway through — so good' },
-      { from: P_ANNA,  mine: false, timestamp: now() - 60 * 60 * 48, text: 'love the linguistics angle' },
-      { from: MINE,    mine: true,  timestamp: now() - 60 * 60 * 30, read: true, text: "rocky is my favourite character in years" },
-      { from: P_SIS,   mine: false, timestamp: now() - 60 * 60 * 28, text: 'agreed' },
-      { from: P_ANNA,  mine: false, timestamp: now() - 60 * 60 * 24, text: "let's meet sunday 4pm?" },
-    ]);
-  }
-
-  // ── Group: Tuesday D&D 🎲 ──────────────────────────────────────
-  if (contact.alias === 'Tuesday D&D 🎲') {
-    return list('dnd', [
-      { from: P_LEAD,  mine: false, timestamp: now() - 60 * 60 * 72, text: 'Session 14 recap up on the wiki' },
-      { from: P_ANNA,  mine: false, timestamp: now() - 60 * 60 * 72, text: '🙏' },
-      { from: P_TYRA,  mine: false, timestamp: now() - 60 * 60 * 50, text: 'can we start 30min late next tuesday? commute issue' },
-      { from: P_LEAD,  mine: false, timestamp: now() - 60 * 60 * 50, text: 'sure' },
-      { from: MINE,    mine: true,  timestamp: now() - 60 * 60 * 49, read: true, text: 'works for me' },
-      { from: P_LEAD,  mine: false, timestamp: now() - 60 * 60 * 32, text: 'we pick up where we left — in the dragons cave' },
-      { from: P_ANNA,  mine: false, timestamp: now() - 60 * 60 * 32, text: 'excited 🐉' },
-    ]);
-  }
-
-  // ── Channel: dchain_updates ────────────────────────────────────
-  if (contact.username === 'dchain_updates') {
-    return list('dchain_updates', [
-      { from: peer, mine: false, timestamp: now() - 60 * 60 * 96, text: '🔨 v0.0.1-alpha tagged on Gitea' },
-      { from: peer, mine: false, timestamp: now() - 60 * 60 * 72, text: 'PBFT equivocation-detection тесты зелёные' },
-      { from: peer, mine: false, timestamp: now() - 60 * 60 * 60, text: 'New: /api/peers теперь включает peer-version info' },
-      { from: peer, mine: false, timestamp: now() - 60 * 60 * 48, text: '📘 Docs overhaul merged: docs/README.md' },
-      { from: peer, mine: false, timestamp: now() - 60 * 60 * 36, text: 'Schema migration scaffold landed (no-op для текущей версии)' },
-      { from: peer, mine: false, timestamp: now() - 60 * 60 * 20, text: '🚀 v0.0.1 released' },
-      { from: peer, mine: false, timestamp: now() - 60 * 60 * 20 + 10, text: 'Includes: auto-update from Gitea, peer-version gossip, schema migrations' },
-      { from: peer, mine: false, timestamp: now() - 60 * 60 * 20 + 20, text: 'Check /api/well-known-version for the full feature list' },
-      { from: peer, mine: false, timestamp: now() - 60 * 60 * 12, text: 'Thanks to all testers — feedback drives the roadmap 🙏' },
-      { from: peer, mine: false, timestamp: now() - 60 * 60 * 3, text: 'v0.0.2 roadmap published: https://git.vsecoder.vodka/vsecoder/dchain' },
-      { from: peer, mine: false, timestamp: now() - 60 * 30, text: 'quick heads-up: nightly builds switching to new docker-slim base' },
-    ]);
-  }
-
-  // ── Channel: Relay broadcasts ──────────────────────────────────
-  if (contact.alias === '⚡ Relay broadcasts') {
-    return list('relay_bc', [
-      { from: peer, mine: false, timestamp: now() - 60 * 60 * 48, text: 'Relay fleet snapshot: 12 active, 3 inactive' },
-      { from: peer, mine: false, timestamp: now() - 60 * 60 * 40, text: 'Relay #3 came online in US-east' },
-      { from: peer, mine: false, timestamp: now() - 60 * 60 * 30, text: 'Validator set updated: 3→4' },
-      { from: peer, mine: false, timestamp: now() - 60 * 60 * 20, text: 'PBFT view-change детектирован и отработан на блоке 184120' },
-      { from: peer, mine: false, timestamp: now() - 60 * 60 * 15, text: 'Mailbox eviction ran — 42 stale envelopes' },
-      { from: peer, mine: false, timestamp: now() - 60 * 60 * 5, text: 'Relay #8 slashed for equivocation — evidence at block 184202' },
-      { from: peer, mine: false, timestamp: now() - 60 * 60 * 2, text: 'Relay #12 came online in EU-west, registering now…' },
-    ]);
-  }
-
-  // ── Channel: Tech news ────────────────────────────────────────
-  if (contact.alias === '📰 Tech news') {
-    return list('tech_news', [
-      { from: peer, mine: false, timestamp: now() - 60 * 60 * 120, text: 'Rust 1.78 released — new lints for raw pointers' },
-      { from: peer, mine: false, timestamp: now() - 60 * 60 * 100, text: 'Go 1.23 ships range-over-func officially' },
-      { from: peer, mine: false, timestamp: now() - 60 * 60 * 80, text: 'Expo SDK 54 drops — new-architecture default' },
-      { from: peer, mine: false, timestamp: now() - 60 * 60 * 60, text: 'CVE-2026-1337 patched in libsodium (update your keys)' },
-      { from: peer, mine: false, timestamp: now() - 60 * 60 * 40, text: 'Matrix protocol adds post-quantum handshakes' },
-      {
-        from: peer, mine: false, timestamp: now() - 60 * 60 * 30, text: 'Data-center aerial view — new hyperscaler in Iceland',
-        attachment: {
-          kind: 'image',
-          uri:  'https://images.unsplash.com/photo-1558494949-ef010cbdcc31?w=800',
-          width: 800, height: 533, mime: 'image/jpeg',
-        },
-      },
-      { from: peer, mine: false, timestamp: now() - 60 * 60 * 20, text: 'IETF draft: "DNS-over-blockchain"' },
-      { from: peer, mine: false, timestamp: now() - 60 * 60 * 6, text: 'GitHub tightens 2FA defaults for orgs' },
-    ]);
-  }
-
-  // ── Channel: Design inspo (unread=12) ──────────────────────────
-  if (contact.alias === '🎨 Design inspo') {
-    return list('design_inspo', [
-      { from: peer, mine: false, timestamp: now() - 60 * 60 * 160, text: 'Weekly pick: Linear UI v3 breakdown' },
-      { from: peer, mine: false, timestamp: now() - 60 * 60 * 140, text: 'Figma file of the week: "Command bar patterns"' },
-      { from: peer, mine: false, timestamp: now() - 60 * 60 * 120, text: 'Motion study: Stripe checkout shake-error animation' },
-      { from: peer, mine: false, timestamp: now() - 60 * 60 * 100, text: "10 great empty-state illustrations (blogpost)" },
-      { from: peer, mine: false, timestamp: now() - 60 * 60 * 80, text: 'Tool: Hatch — colour-palette extractor from photos' },
-      { from: peer, mine: false, timestamp: now() - 60 * 60 * 60, text: '🔮 Trend watch: glassmorphism is back (again)' },
-      { from: peer, mine: false, timestamp: now() - 60 * 60 * 40, text: 'Twitter thread: why rounded buttons are the default' },
-      { from: peer, mine: false, timestamp: now() - 60 * 60 * 20, text: 'Framer templates — black friday sale' },
-      { from: peer, mine: false, timestamp: now() - 60 * 60 * 3, text: 'New typeface: "Grotesk Pro" — free for personal use' },
-    ]);
-  }
-
-  // ── Channel: NBA scores ────────────────────────────────────────
-  if (contact.alias === '🏀 NBA scores') {
-    return list('nba', [
-      { from: peer, mine: false, timestamp: now() - 60 * 60 * 160, text: 'Lakers 112 — Warriors 108 (OT)' },
-      { from: peer, mine: false, timestamp: now() - 60 * 60 * 130, text: 'Celtics 128 — Heat 115' },
-      { from: peer, mine: false, timestamp: now() - 60 * 60 * 100, text: 'Nuggets 119 — Thunder 102' },
-      { from: peer, mine: false, timestamp: now() - 60 * 60 * 70, text: "Knicks 101 — Bulls 98" },
-      { from: peer, mine: false, timestamp: now() - 60 * 60 * 48, text: 'Mavericks 130 — Kings 127' },
-      { from: peer, mine: false, timestamp: now() - 60 * 60 * 24, text: 'Bucks 114 — Sixers 110' },
-      { from: peer, mine: false, timestamp: now() - 60 * 60 * 4, text: 'Live: Lakers leading 78-72 at half' },
-    ]);
-  }
-
-  return [];
-}
-
-// ─── Hook ──────────────────────────────────────────────────────────
-
-export function useDevSeed() {
-  const contacts    = useStore(s => s.contacts);
-  const setContacts = useStore(s => s.setContacts);
-  const setMessages = useStore(s => s.setMessages);
-
-  useEffect(() => {
-    if (contacts.length > 0) return;
-    setContacts(mockContacts);
-    for (const c of mockContacts) {
-      const msgs = mockMessagesFor(c);
-      if (msgs.length > 0) setMessages(c.address, msgs);
-    }
-  }, [contacts.length, setContacts, setMessages]);
-}

client-app/lib/devSeedFeed.ts

@@ -1,180 +0,0 @@
-/**
- * Dev-only mock posts for the feed.
- *
- * Why: in __DEV__ before any real posts exist on the node, the timeline/
- * for-you/trending tabs come back empty. Empty state is fine visually but
- * doesn't let you test scrolling, like animations, view-counter bumps,
- * navigation to post detail, etc. This module injects a small set of
- * synthetic posts so the UI has something to chew on.
- *
- * Gating:
- *  - Only active when __DEV__ === true (stripped from production builds).
- *  - Only surfaces when the REAL API returns an empty array. If the node
- *    is returning actual posts, we trust those and skip the mocks.
- *
- * These posts have made-up post_ids — tapping on them to open detail
- * WILL 404 against the real backend. That's intentional — the mock is
- * purely for scroll / tap-feedback testing.
- */
-import type { FeedPostItem } from './feed';
-
-// Fake hex-like pubkeys so Avatar's colour hash still looks varied.
-function fakeAddr(seed: number): string {
-  const h = (seed * 2654435761).toString(16).padStart(8, '0');
-  return (h + h + h + h).slice(0, 64);
-}
-
-function fakePostID(n: number): string {
-  return `dev${String(n).padStart(29, '0')}`;
-}
-
-const NOW = Math.floor(Date.now() / 1000);
-
-// Small curated pool of posts covering the render surface we care about:
-// plain text, hashtag variety, different lengths, likes / views spread,
-// reply/quote references, one with an attachment marker.
-const SEED_POSTS: FeedPostItem[] = [
-  {
-    post_id:    fakePostID(1),
-    author:     fakeAddr(1),
-    content:    'Добро пожаловать в ленту DChain. Это #DEV-посты — они видны только пока реальная лента пустая.',
-    created_at: NOW - 60,
-    size:       200,
-    hosting_relay: fakeAddr(100),
-    views: 127, likes: 42,
-    has_attachment: false,
-    hashtags: ['dev'],
-  },
-  {
-    post_id:    fakePostID(2),
-    author:     fakeAddr(2),
-    content:    'Пробую новую ленту #twitter-style. Лайки, просмотры, подписки — всё on-chain, тела постов — off-chain в mailbox релея.',
-    created_at: NOW - 540,
-    size:       310,
-    hosting_relay: fakeAddr(100),
-    views: 89, likes: 23,
-    has_attachment: false,
-    hashtags: ['twitter'],
-  },
-  {
-    post_id:    fakePostID(3),
-    author:     fakeAddr(3),
-    content:    'Сжатие изображений — максимальное на клиенте (WebP Q=50 @1080p), плюс серверный EXIF-скраб через stdlib re-encode. GPS-координаты из EXIF больше никогда не утекают. #privacy',
-    created_at: NOW - 1200,
-    size:       420,
-    hosting_relay: fakeAddr(100),
-    views: 312, likes: 78,
-    has_attachment: true,
-    hashtags: ['privacy'],
-  },
-  {
-    post_id:    fakePostID(4),
-    author:     fakeAddr(4),
-    content:    'Короткий пост.',
-    created_at: NOW - 3600,
-    size:       128,
-    hosting_relay: fakeAddr(100),
-    views: 12, likes: 3,
-    has_attachment: false,
-  },
-  {
-    post_id:    fakePostID(5),
-    author:     fakeAddr(1),
-    content:    'Отвечаю сам себе — фича threads пока через reply_to только, без UI thread-виджета.',
-    created_at: NOW - 7200,
-    size:       220,
-    hosting_relay: fakeAddr(100),
-    views: 45, likes: 11,
-    has_attachment: false,
-    reply_to: fakePostID(1),
-  },
-  {
-    post_id:    fakePostID(6),
-    author:     fakeAddr(5),
-    content:    '#golang + #badgerdb + #libp2p = DChain бэкенд. Пять package в test suite, все зелёные.',
-    created_at: NOW - 10800,
-    size:       180,
-    hosting_relay: fakeAddr(100),
-    views: 201, likes: 66,
-    has_attachment: false,
-    hashtags: ['golang', 'badgerdb', 'libp2p'],
-  },
-  {
-    post_id:    fakePostID(7),
-    author:     fakeAddr(6),
-    content:    'Feed-mailbox хранит тела постов до 30 дней (настраиваемо через DCHAIN_FEED_TTL_DAYS). Потом BadgerDB выселяет автоматически — chain-метаданные остаются навсегда.',
-    created_at: NOW - 14400,
-    size:       380,
-    hosting_relay: fakeAddr(100),
-    views: 156, likes: 48,
-    has_attachment: false,
-  },
-  {
-    post_id:    fakePostID(8),
-    author:     fakeAddr(7),
-    content:    'Pricing: BasePostFee = 1000 µT (0.001 T) + 1 µT за каждый байт. Уходит владельцу релея, принявшего пост.',
-    created_at: NOW - 21600,
-    size:       250,
-    hosting_relay: fakeAddr(100),
-    views: 78, likes: 22,
-    has_attachment: false,
-  },
-  {
-    post_id:    fakePostID(9),
-    author:     fakeAddr(8),
-    content:    'Twitter-like, но без миллиардов долларов на инфраструктуру — каждый оператор ноды платит за свой кусок хостинга и зарабатывает на публикациях. #decentralised #messaging',
-    created_at: NOW - 43200,
-    size:       340,
-    hosting_relay: fakeAddr(100),
-    views: 412, likes: 103,
-    has_attachment: false,
-    hashtags: ['decentralised', 'messaging'],
-  },
-  {
-    post_id:    fakePostID(10),
-    author:     fakeAddr(9),
-    content:    'Короче. Лайк = on-chain tx с fee 1000 µT. Дорого для спама, дёшево для реального лайка. Пока без батчинга, но в плане. #design',
-    created_at: NOW - 64800,
-    size:       200,
-    hosting_relay: fakeAddr(100),
-    views: 92, likes: 29,
-    has_attachment: false,
-    hashtags: ['design'],
-  },
-  {
-    post_id:    fakePostID(11),
-    author:     fakeAddr(2),
-    content:    'Follow граф на chain: двусторонний индекс (forward + inbound), так что Followers() и Following() — оба O(M).',
-    created_at: NOW - 86400 - 1000,
-    size:       230,
-    hosting_relay: fakeAddr(100),
-    views: 61, likes: 14,
-    has_attachment: false,
-  },
-  {
-    post_id:    fakePostID(12),
-    author:     fakeAddr(10),
-    content:    'Рекомендации (For You): берём последние 48ч постов, фильтруем подписки + уже лайкнутые + свои, ранжируем по likes × 3 + views. Версия 1 — будет умнее. #recsys',
-    created_at: NOW - 129600,
-    size:       290,
-    hosting_relay: fakeAddr(100),
-    views: 189, likes: 58,
-    has_attachment: false,
-    hashtags: ['recsys'],
-  },
-];
-
-/**
- * Returns the dev-seed post list. Only returns actual items in dev
- * builds; release bundles return an empty array so fake posts never
- * appear in production.
- *
- * We use the runtime `globalThis.__DEV__` lookup rather than the typed
- * `__DEV__` global because some builds can have the TS typing
- * out-of-sync with the actual injected value.
- */
-export function getDevSeedFeed(): FeedPostItem[] {
-  const g = globalThis as unknown as { __DEV__?: boolean };
-  if (g.__DEV__ !== true) return [];
-  return SEED_POSTS;
-}

client-app/lib/storage.ts

@@ -14,6 +14,12 @@ const KEYFILE_KEY = 'dchain_keyfile';
 const CONTACTS_KEY = 'dchain_contacts';
 const SETTINGS_KEY = 'dchain_settings';
 const CHATS_KEY = 'dchain_chats';
+// Remembers (locally, per install) that this device's X25519 pub has been
+// successfully linked on-chain at least once. Distinguishes "first boot,
+// not registered yet" from "we were registered and then revoked by another
+// device". The second case triggers self-wipe. Stored in AsyncStorage —
+// if it's missing, we simply re-link.
+const DEVICE_REGISTERED_KEY = 'dchain_device_registered';
 
 /** Save the key file in secure storage (encrypted on device). */
 export async function saveKeyFile(kf: KeyFile): Promise<void> {
@@ -99,3 +105,57 @@ export async function appendMessage(chatId: string, msg: CachedMessage): Promise
   const trimmed = msgs.slice(-500);
   await AsyncStorage.setItem(`${CHATS_KEY}_${chatId}`, JSON.stringify(trimmed));
 }
+
+// ─── Multi-device bookkeeping (v2.2.0) ────────────────────────────────────
+
+/**
+ * isDeviceRegistered returns true if this device has ever successfully
+ * linked its X25519 pub on-chain under the current master identity.
+ * A true-then-absent transition (registered → not in chain's active list)
+ * is interpreted as a remote revoke and triggers self-wipe.
+ */
+export async function isDeviceRegistered(): Promise<boolean> {
+  return (await AsyncStorage.getItem(DEVICE_REGISTERED_KEY)) === '1';
+}
+
+/** markDeviceRegistered is called after a LINK_DEVICE commits or is
+    observed in the registry on startup. */
+export async function markDeviceRegistered(): Promise<void> {
+  await AsyncStorage.setItem(DEVICE_REGISTERED_KEY, '1');
+}
+
+/** clearDeviceRegistered is part of wipeAllLocalState; also called on
+    explicit logout. */
+export async function clearDeviceRegistered(): Promise<void> {
+  await AsyncStorage.removeItem(DEVICE_REGISTERED_KEY);
+}
+
+/**
+ * wipeAllLocalState zeroes out every on-device artifact tied to the
+ * current identity: secure-store key, settings, contacts, chats cache,
+ * registered-device marker. Safe to call multiple times.
+ *
+ * Called in two scenarios:
+ *   1. Explicit "Delete account" in Settings.
+ *   2. Self-detected revoke — the chain says our X25519 pub is no longer
+ *      in the active registry but we previously marked it registered,
+ *      so another device issued UNLINK_DEVICE against us. We must not
+ *      keep using the master priv any more — it still works at the
+ *      crypto level, but the social contract is that we're revoked.
+ */
+export async function wipeAllLocalState(): Promise<void> {
+  // Secure store (key).
+  await SecureStore.deleteItemAsync(KEYFILE_KEY).catch(() => {});
+  // AsyncStorage — enumerate our known keys. We don't clear() the whole
+  // store because a share-provider or other app shard could live there.
+  const ks = await AsyncStorage.getAllKeys();
+  const ours = ks.filter(k =>
+    k === CONTACTS_KEY ||
+    k === SETTINGS_KEY ||
+    k === DEVICE_REGISTERED_KEY ||
+    k.startsWith(`${CHATS_KEY}_`),
+  );
+  if (ours.length > 0) {
+    await AsyncStorage.multiRemove(ours);
+  }
+}

client-app/lib/utils.ts

@@ -1,5 +1,23 @@
 import { clsx, type ClassValue } from 'clsx';
 import { twMerge } from 'tailwind-merge';
+import { router } from 'expo-router';
+
+/**
+ * Navigate back, or fall back to a sensible default route if there's
+ * no screen to pop to.
+ *
+ * Without this, an opened route entered via deep link / direct push
+ * (profile, feed/[id], etc.) would emit the "action 'GO_BACK' was not
+ * handled by any navigator" dev warning and do nothing — user ends up
+ * stuck. Default fallback is the chats list (root of the app).
+ */
+export function safeBack(fallback: string = '/(app)/chats'): void {
+  if (router.canGoBack()) {
+    router.back();
+  } else {
+    router.replace(fallback as never);
+  }
+}
 
 export function cn(...inputs: ClassValue[]) {
   return twMerge(clsx(inputs));

cmd/node/main.go

@@ -29,6 +29,8 @@ import (
 	"os"
 	"os/signal"
 	"path/filepath"
+	"runtime"
+	"runtime/debug"
 	"strings"
 	"sync"
 	"syscall"
@@ -114,6 +116,16 @@ func main() {
 	// only for intentional migrations (e.g. importing data from another chain
 	// into this network) — very dangerous.
 	allowGenesisMismatch := flag.Bool("allow-genesis-mismatch", false, "skip the safety check that aborts when the local genesis hash differs from the seed's. Use only for explicit chain migration.")
+	// ── Resource caps ───────────────────────────────────────────────────────
+	// All four accept 0 meaning "no limit". Enforcement model:
+	//  * CPU  — runtime.GOMAXPROCS(n): Go runtime won't use more than n OS threads for Go code.
+	//  * RAM  — debug.SetMemoryLimit: soft limit, the GC works harder as the heap approaches it.
+	//  * Feed disk — hard refuse of new post bodies once the cap is crossed (existing posts keep serving).
+	//  * Chain disk — warn-only periodic check; we can't hard-reject new blocks without breaking consensus.
+	maxCPU        := flag.Int("max-cpu", int(envUint64Or("DCHAIN_MAX_CPU", 0)), "max CPU cores the node may use (GOMAXPROCS). 0 = all (env: DCHAIN_MAX_CPU)")
+	maxRAMMB      := flag.Uint64("max-ram-mb", envUint64Or("DCHAIN_MAX_RAM_MB", 0), "soft Go heap limit in MiB (GOMEMLIMIT). 0 = unlimited (env: DCHAIN_MAX_RAM_MB)")
+	feedDiskMB    := flag.Uint64("feed-disk-limit-mb", envUint64Or("DCHAIN_FEED_DISK_LIMIT_MB", 0), "disk quota for post bodies in MiB; new posts are refused with 507 once crossed. 0 = unlimited (env: DCHAIN_FEED_DISK_LIMIT_MB)")
+	chainDiskMB   := flag.Uint64("chain-disk-limit-mb", envUint64Or("DCHAIN_CHAIN_DISK_LIMIT_MB", 0), "advisory disk cap for the chain DB dir in MiB; exceeding it logs a loud WARN every minute. 0 = unlimited (env: DCHAIN_CHAIN_DISK_LIMIT_MB)")
 	showVersion := flag.Bool("version", false, "print version info and exit")
 	flag.Parse()
 
@@ -128,6 +140,10 @@ func main() {
 	// so subsequent logs inherit the format.
 	setupLogging(*logFormat)
 
+	// Apply CPU / RAM caps before anything else spins up so the runtime
+	// picks them up at first goroutine/heap allocation.
+	applyResourceCaps(*maxCPU, *maxRAMMB)
+
 	// Wire API access-control. A non-empty token gates writes; adding
 	// --api-private also gates reads. Logged up-front so the operator
 	// sees what mode they're in.
@@ -641,12 +657,24 @@ func main() {
 
 	// --- Feed mailbox (social-feed post bodies, v2.0.0) ---
 	feedTTL := time.Duration(*feedTTLDays) * 24 * time.Hour
-	feedMailbox, err := relay.OpenFeedMailbox(*feedDB, feedTTL)
+	feedQuotaBytes := int64(*feedDiskMB) * 1024 * 1024
+	feedMailbox, err := relay.OpenFeedMailbox(*feedDB, feedTTL, feedQuotaBytes)
 	if err != nil {
 		log.Fatalf("[NODE] feed mailbox: %v", err)
 	}
 	defer feedMailbox.Close()
-	log.Printf("[NODE] feed mailbox: %s (TTL %d days)", *feedDB, *feedTTLDays)
+	if feedQuotaBytes > 0 {
+		log.Printf("[NODE] feed mailbox: %s (TTL %d days, disk quota %d MiB)", *feedDB, *feedTTLDays, *feedDiskMB)
+	} else {
+		log.Printf("[NODE] feed mailbox: %s (TTL %d days, no disk quota)", *feedDB, *feedTTLDays)
+	}
+
+	// Advisory chain-disk watcher. We can't refuse new blocks (consensus
+	// would stall), so instead we walk the chain DB dir every minute and
+	// log a loud WARN if the operator's budget is exceeded. Zero = disabled.
+	if *chainDiskMB > 0 {
+		go watchChainDisk(*dbPath, int64(*chainDiskMB)*1024*1024)
+	}
 
 	// Push-notify bus consumers whenever a fresh envelope lands in the
 	// mailbox. Clients subscribed to `inbox:<my_x25519>` (via WS) get the
@@ -850,6 +878,7 @@ func main() {
 		IdentityInfo: func(pubKeyOrAddr string) (*blockchain.IdentityInfo, error) {
 			return chain.IdentityInfo(pubKeyOrAddr)
 		},
+		DevicesOf:    chain.DevicesOf,
 		ValidatorSet: chain.ValidatorSet,
 		SubmitTx: func(tx *blockchain.Transaction) error {
 			if err := engine.AddTransaction(tx); err != nil {
@@ -1291,11 +1320,38 @@ type keyJSON struct {
 }
 
 func loadOrCreateIdentity(keyFile string) *identity.Identity {
-	if data, err := os.ReadFile(keyFile); err == nil {
+	// Key-file handling has a silent-failure mode that cost a genesis
+	// validator 21M tokens in the wild: if the file exists but we can't
+	// read it (e.g. mounted read-only under a different UID), ReadFile
+	// returns an error, we fall through to "generate", and the operator
+	// ends up with an ephemeral key whose pubkey doesn't match what's in
+	// keys/node.json on disk. Genesis allocation then lands on the
+	// ephemeral key that vanishes on restart.
+	//
+	// Distinguish "file doesn't exist" (normal — first boot, create)
+	// from "file exists but unreadable" (operator error — fail loudly).
+	if info, err := os.Stat(keyFile); err == nil {
+		// File is there. Any read failure now is an operator problem,
+		// not a bootstrap case.
+		_ = info
+		data, err := os.ReadFile(keyFile)
+		if err != nil {
+			log.Fatalf("[NODE] key file %s exists but can't be read: %v\n"+
+				"\thint: check file perms (should be readable by the node user) "+
+				"and that the mount isn't unexpectedly read-only.",
+				keyFile, err)
+		}
 		var kj keyJSON
-		if err := json.Unmarshal(data, &kj); err == nil {
-			if id, err := identity.FromHexFull(kj.PubKey, kj.PrivKey, kj.X25519Pub, kj.X25519Priv); err == nil {
-				// If the file is missing X25519 keys, backfill and re-save.
+		if err := json.Unmarshal(data, &kj); err != nil {
+			log.Fatalf("[NODE] key file %s is not valid JSON: %v", keyFile, err)
+		}
+		id, err := identity.FromHexFull(kj.PubKey, kj.PrivKey, kj.X25519Pub, kj.X25519Priv)
+		if err != nil {
+			log.Fatalf("[NODE] key file %s is valid JSON but identity decode failed: %v",
+				keyFile, err)
+		}
+		// If the file is missing X25519 keys, backfill and re-save (best-effort,
+		// ignore write failure on read-only mounts).
 		if kj.X25519Pub == "" {
 			kj.X25519Pub = id.X25519PubHex()
 			kj.X25519Priv = id.X25519PrivHex()
@@ -1305,9 +1361,12 @@ func loadOrCreateIdentity(keyFile string) *identity.Identity {
 		}
 		log.Printf("[NODE] loaded identity from %s", keyFile)
 		return id
+	} else if !os.IsNotExist(err) {
+		// Something other than "file not found" — permission on the
+		// containing directory, broken symlink, etc. Also fail loudly.
+		log.Fatalf("[NODE] stat %s: %v", keyFile, err)
 	}
-		}
-	}
+	// File genuinely doesn't exist — first boot. Generate + save.
 	id, err := identity.Generate()
 	if err != nil {
 		log.Fatalf("generate identity: %v", err)
@@ -1320,7 +1379,9 @@ func loadOrCreateIdentity(keyFile string) *identity.Identity {
 	}
 	data, _ := json.MarshalIndent(kj, "", "  ")
 	if err := os.WriteFile(keyFile, data, 0600); err != nil {
-		log.Printf("[NODE] warning: could not save key: %v", err)
+		log.Printf("[NODE] warning: could not save key to %s: %v "+
+			"(ephemeral key in use — this node's identity will change on restart!)",
+			keyFile, err)
 	} else {
 		log.Printf("[NODE] new identity saved to %s", keyFile)
 	}
@@ -1440,6 +1501,61 @@ func shortKeys(keys []string) []string {
 // "text" (default) is handler-default human-readable format, same as bare
 // log.Printf. "json" emits one JSON object per line with `time/level/msg`
 // + any key=value attrs — what Loki/ELK ingest natively.
+// applyResourceCaps wires the --max-cpu and --max-ram-mb flags into the Go
+// runtime. Both are soft-ish: CPU clamps GOMAXPROCS (Go scheduler won't use
+// more OS threads for Go code, though blocking syscalls can still spawn
+// more); RAM sets GOMEMLIMIT (the GC tightens its collection schedule as
+// the heap approaches the cap but cannot *force* a kernel OOM-free). Use
+// container limits (cgroup / Docker --memory / --cpus) alongside these
+// for a real ceiling — this is "please play nice", not "hard sandbox".
+func applyResourceCaps(maxCPU int, maxRAMMB uint64) {
+	if maxCPU > 0 {
+		prev := runtime.GOMAXPROCS(maxCPU)
+		log.Printf("[NODE] CPU cap: GOMAXPROCS %d → %d", prev, maxCPU)
+	}
+	if maxRAMMB > 0 {
+		bytes := int64(maxRAMMB) * 1024 * 1024
+		debug.SetMemoryLimit(bytes)
+		log.Printf("[NODE] RAM cap: GOMEMLIMIT = %d MiB (soft, GC-enforced)", maxRAMMB)
+	}
+}
+
+// watchChainDisk periodically walks the chain BadgerDB directory and logs
+// a WARN line whenever its size exceeds `limitBytes`. Runs forever — the
+// process lifetime bounds it. We deliberately do *not* stop block
+// production when the cap is crossed: a validator that refuses to apply
+// blocks stalls consensus for everyone on the chain, which is worse than
+// using more disk than the operator wanted. Treat this as a monitoring
+// signal, e.g. feed it to Prometheus via an alertmanager scrape.
+func watchChainDisk(dir string, limitBytes int64) {
+	tick := time.NewTicker(60 * time.Second)
+	defer tick.Stop()
+	for ; ; <-tick.C {
+		used := dirSize(dir)
+		if used > limitBytes {
+			log.Printf("[NODE] WARN chain disk over quota: %d MiB used > %d MiB limit at %s",
+				used>>20, limitBytes>>20, dir)
+		}
+	}
+}
+
+// dirSize returns the total byte size of all regular files under root,
+// recursively. Errors on individual entries are ignored — this is an
+// advisory metric, not a filesystem audit.
+func dirSize(root string) int64 {
+	var total int64
+	_ = filepath.Walk(root, func(_ string, info os.FileInfo, err error) error {
+		if err != nil || info == nil {
+			return nil
+		}
+		if !info.IsDir() {
+			total += info.Size()
+		}
+		return nil
+	})
+	return total
+}
+
 func setupLogging(format string) {
 	var handler slog.Handler
 	switch strings.ToLower(format) {

deploy/prod/Dockerfile.slim

@@ -13,7 +13,7 @@
 # testnet validator.
 
 # ---- build stage ----
-FROM golang:1.24-alpine AS builder
+FROM golang:1.25-alpine AS builder
 WORKDIR /app
 
 COPY go.mod go.sum ./
@@ -46,7 +46,15 @@ RUN apk add --no-cache ca-certificates tzdata
 
 # Run as unprivileged user by default. Operators can override with --user root
 # if they need to bind privileged ports (shouldn't be necessary behind Caddy).
-RUN addgroup -S dchain && adduser -S -G dchain dchain
+#
+# IMPORTANT: /data must exist + be owned by dchain BEFORE the VOLUME
+# directive. Docker copies the directory ownership of the mount point
+# into any fresh named volume at first-attach time; skip this and
+# operators get "mkdir: permission denied" when the node tries to
+# create /data/chain as the dchain user.
+RUN addgroup -S dchain && adduser -S -G dchain dchain \
+ && mkdir -p /data \
+ && chown dchain:dchain /data
 
 COPY --from=builder /bin/node   /usr/local/bin/node
 COPY --from=builder /bin/client /usr/local/bin/client

deploy/single/join.sh

@@ -0,0 +1,202 @@
+#!/usr/bin/env bash
+# rejoin.sh — полная переустановка dchain joiner-ноды с нуля.
+# Публичный доступ без Caddy/TLS, без API-токена (на свой страх и риск).
+# Запускать БЕЗ sudo.
+
+set -euo pipefail
+
+# ── КОНФИГ ─────────────────────────────────────────────────────────────
+SEED_HTTP="${SEED_HTTP:-http://62.171.151.182:8082}"
+SEED_P2P_IP="${SEED_P2P_IP:-62.171.151.182}"
+SEED_P2P_PORT="${SEED_P2P_PORT:-4005}"
+REPO_URL="${REPO_URL:-https://git.vsecoder.vodka/vsecoder/dchain.git}"
+WORKDIR="${WORKDIR:-$HOME/dchain}"
+LOCAL_P2P_PORT="${LOCAL_P2P_PORT:-4001}"
+LOCAL_HTTP_PORT="${LOCAL_HTTP_PORT:-8082}"
+# ───────────────────────────────────────────────────────────────────────
+
+log()  { printf '\033[1;34m==>\033[0m %s\n' "$*"; }
+warn() { printf '\033[1;33m!!\033[0m  %s\n' "$*" >&2; }
+die()  { printf '\033[1;31mXX\033[0m  %s\n' "$*" >&2; exit 1; }
+need() { command -v "$1" >/dev/null || die "need $1 installed"; }
+
+# ── 0. Требования ──────────────────────────────────────────────────────
+[[ $EUID -eq 0 ]] && die "don't run as root — use your user account, sudo is used per-command"
+need docker; need git; need curl; need jq
+sudo -v
+
+# ── 1. Снести предыдущее состояние ─────────────────────────────────────
+log "stopping any existing dchain stack & purging volumes"
+if [[ -d "$WORKDIR/deploy/single" ]]; then
+  (cd "$WORKDIR/deploy/single" && sudo docker compose down -v 2>/dev/null) || true
+fi
+sudo docker rm -f dchain_node dchain_caddy dchain 2>/dev/null || true
+mapfile -t stale_vols < <(sudo docker volume ls -q | grep -E '^(dchain|dchain-single)' || true)
+(( ${#stale_vols[@]} > 0 )) && sudo docker volume rm "${stale_vols[@]}" 2>/dev/null || true
+
+# ── 2. Свежий репозиторий ──────────────────────────────────────────────
+log "fetching repo → $WORKDIR"
+if [[ -d "$WORKDIR/.git" ]]; then
+  git -C "$WORKDIR" fetch --all --tags --prune
+  git -C "$WORKDIR" reset --hard origin/main
+else
+  rm -rf "$WORKDIR"
+  git clone "$REPO_URL" "$WORKDIR"
+fi
+cd "$WORKDIR/deploy/single"
+
+# ── 3. keys/ под UID 100 ───────────────────────────────────────────────
+log "preparing keys/ for container UID 100:101"
+mkdir -p keys
+sudo chown 100:101 keys
+sudo chmod 755 keys
+[[ -f keys/node.json ]] && { sudo chown 100:101 keys/node.json; sudo chmod 600 keys/node.json; }
+
+# ── 4. Slim-образ ──────────────────────────────────────────────────────
+log "building dchain image (slim)"
+IMAGE=$(sudo docker build -q -f ../prod/Dockerfile.slim ../..)
+[[ -z "$IMAGE" ]] && die "docker build failed"
+
+# ── 5. Ключ ноды ───────────────────────────────────────────────────────
+if [[ ! -f keys/node.json ]]; then
+  log "generating node identity"
+  sudo docker run --rm --entrypoint /usr/local/bin/client \
+    --user 100:101 \
+    -v "$PWD/keys:/out" \
+    "$IMAGE" \
+    keygen --out /out/node.json
+else
+  log "reusing existing keys/node.json"
+fi
+sudo chown 100:101 keys/node.json
+sudo chmod 600 keys/node.json
+
+# ── 6. peer_id seed'a ──────────────────────────────────────────────────
+log "fetching seed peer_id from $SEED_HTTP/stats"
+SEED_PEER_ID=$(curl -sfL "$SEED_HTTP/stats" | jq -r '.node.peer_id // empty')
+[[ -z "$SEED_PEER_ID" ]] && die "can't reach seed at $SEED_HTTP or peer_id missing"
+log "seed peer_id = $SEED_PEER_ID"
+
+# ── 7. Публичный IP ────────────────────────────────────────────────────
+PUBLIC_IP="${PUBLIC_IP:-$(curl -sfL https://api.ipify.org || true)}"
+[[ -z "$PUBLIC_IP" ]] && die "can't detect public IP; export PUBLIC_IP=x.x.x.x и перезапусти"
+log "public IP = $PUBLIC_IP"
+
+# ── 8. node.env (без токена, без genesis) ──────────────────────────────
+log "writing node.env"
+cp -f node.env.example node.env
+
+# удалить из example'а значения, которые мы хотим держать под своим контролем,
+# чтобы они не перекрыли наши append'ы снизу
+sudo sed -i -E '/^(#\s*)?DCHAIN_(GENESIS|API_TOKEN|API_PRIVATE|JOIN|PEERS|ANNOUNCE|DB|MAILBOX_DB|FEED_DB|REGISTER_RELAY|RELAY_FEE|FEED_DISK_LIMIT_MB|CHAIN_DISK_LIMIT_MB|UPDATE_SOURCE_URL)=/d' node.env
+
+sudo tee -a node.env > /dev/null <<EOF
+
+# ── AUTO-GENERATED BY rejoin.sh ─────────────────────────────────────
+# joiner → seed $SEED_HTTP  (public node, no token)
+DCHAIN_JOIN=$SEED_HTTP
+DCHAIN_PEERS=/ip4/$SEED_P2P_IP/tcp/$SEED_P2P_PORT/p2p/$SEED_PEER_ID
+DCHAIN_ANNOUNCE=/ip4/$PUBLIC_IP/tcp/$LOCAL_P2P_PORT
+
+DCHAIN_DB=/data/chain
+DCHAIN_MAILBOX_DB=/data/mailbox
+DCHAIN_FEED_DB=/data/feed
+
+DCHAIN_REGISTER_RELAY=true
+DCHAIN_RELAY_FEE=1000
+
+DCHAIN_FEED_DISK_LIMIT_MB=4096
+DCHAIN_CHAIN_DISK_LIMIT_MB=20480
+
+DCHAIN_UPDATE_SOURCE_URL=https://git.vsecoder.vodka/api/v1/repos/vsecoder/dchain/releases/latest
+EOF
+
+# ── 9. Compose: прямой проброс 4001+8080 наружу, Caddy снести навсегда ─
+log "patching docker-compose.yml: direct ports, caddy removed"
+python3 - <<PY
+import re, pathlib
+p = pathlib.Path('docker-compose.yml')
+src = p.read_text()
+
+# 9a. Вырезать весь сервис caddy (от "  caddy:" до следующего сервиса
+# того же уровня или конца блока services).
+src = re.sub(
+    r'(?ms)^  caddy:\n(?:(?:    .*\n)|\n)+?(?=^  [A-Za-z_-]+:|\Z)',
+    '', src,
+)
+
+# 9b. Убрать зависимости от caddy, если где-то остались.
+src = re.sub(r'(?m)^\s*-\s*caddy\s*$\n', '', src)
+src = re.sub(r'(?m)^\s*depends_on:\s*\n(\s*-\s*caddy\s*\n)+', '', src)
+
+# 9c. Заставить node светить наружу 4001 (libp2p) и 8080 (HTTP).
+# Ищем первый ports: в сервисе node; если его нет — инжектим.
+m = re.search(r'(?ms)^  node:\n(.*?)(?=^  [A-Za-z_-]+:|\Z)', src)
+if not m:
+    raise SystemExit('no `node:` service in compose')
+node_block = m.group(1)
+
+wanted = f'    ports:\n      - "$LOCAL_P2P_PORT:4001"\n      - "$LOCAL_HTTP_PORT:8080"\n'
+
+if re.search(r'(?m)^    ports:', node_block):
+    # Заменить существующий блок ports целиком
+    node_block_new = re.sub(
+        r'(?ms)^    ports:\n(?:      -.*\n)+',
+        wanted, node_block,
+    )
+else:
+    # Добавить сразу после строки "container_name:" (или restart:)
+    node_block_new = re.sub(
+        r'(?m)^(    (?:container_name|restart):.*\n)',
+        r'\\1' + wanted, node_block, count=1,
+    )
+    if node_block_new == node_block:  # fallback — в начало блока
+        node_block_new = wanted + node_block
+
+src = src[:m.start(1)] + node_block_new + src[m.end(1):]
+
+# 9d. Убрать блок expose у node — не нужен, раз ports наружу.
+src = re.sub(
+    r'(?ms)^    expose:\n(?:      -.*\n)+', '', src,
+)
+
+p.write_text(src)
+PY
+
+# ── 10. Подъём ─────────────────────────────────────────────────────────
+log "docker compose up -d"
+sudo docker compose up -d --build
+
+# ── 11. Sanity checks ──────────────────────────────────────────────────
+sleep 3
+log "sanity checks (дай ~30 сек чтобы healthcheck подхватился):"
+set +e
+echo "──── docker compose ps ────"
+sudo docker compose ps
+echo "──── docker logs dchain_node | tail ────"
+sudo docker logs --tail 30 dchain_node 2>&1
+echo "──── /api/netstats ────"
+curl -s "http://localhost:$LOCAL_HTTP_PORT/api/netstats" | jq '.'
+echo "──── seed height (для сверки) ────"
+curl -s "$SEED_HTTP/api/netstats" | jq '.total_blocks'
+
+cat <<EOM
+
+======================================================================
+✓ Готово. Нода публичная, без токена и без TLS.
+
+  API:
+    http://$PUBLIC_IP:$LOCAL_HTTP_PORT/api/netstats
+    http://$PUBLIC_IP:$LOCAL_HTTP_PORT/swagger
+
+  Следи за sync'ом:
+    sudo docker logs -f dchain_node | grep -E 'applied|height|peer'
+
+  Повторный полный сброс:
+    ./rejoin.sh
+
+  Открой в firewall/security-group на этом VPS:
+    - $LOCAL_P2P_PORT/tcp (libp2p)
+    - $LOCAL_HTTP_PORT/tcp (HTTP API)
+======================================================================
+EOM

docker/media-sidecar/Dockerfile

@@ -5,7 +5,7 @@
 # Compose: see docker-compose.yml; node points DCHAIN_MEDIA_SIDECAR_URL at it.
 #
 # Stage 1 — build a tiny static Go binary.
-FROM golang:1.22-alpine AS build
+FROM golang:1.25-alpine AS build
 WORKDIR /src
 # Copy only what we need (the sidecar main is self-contained, no module
 # deps on the rest of the repo, so this is a cheap, cache-friendly build).

docs/ROADMAP.md

@@ -0,0 +1,219 @@
+# Roadmap
+
+Living doc — «куда идём дальше». Два активных вектора: **v2.2.0 multi-device**
+и **desktop Electron client**. Всё что tentative — помечено `?`; всё что
+решено и принято к работе — без знаков.
+
+---
+
+## v2.2.0 — Multi-device (per-device X25519, on-chain device registry)
+
+### Проблема
+
+Сейчас у пользователя одна пара X25519 (хранится в `keyFile`), и relay-mailbox —
+queue с DELETE-после-чтения. При двух устройствах:
+
+- Конверт забирает то устройство, что первое дёрнуло `/relay/inbox` — второе
+  теряет сообщение навсегда.
+- История чатов per-device, не синхронизируется (`AsyncStorage` на каждом
+  устройстве свой).
+
+On-chain часть (posts, follows, tx, wallet) работает нормально — оба устройства
+читают один чейн и видят одно и то же. Чинить надо только мессенджер.
+
+### Решение — путь А (Signal-style): X25519 на устройство + device registry
+
+1. **Master identity = Ed25519** (как сейчас). Подписывает tx, владеет
+   балансом, — один на всю identity.
+2. **X25519 — per-device**. Каждое устройство при первом старте генерит
+   свою пару. Relay-mailbox остаётся queue'ом, но адресуется по
+   **устройству**, не по identity.
+3. **Device registry on-chain**: новые tx-типы `LINK_DEVICE` / `UNLINK_DEVICE`,
+   подписываются master Ed25519, публикуют/отзывают связку
+   `(master_pub → device_x25519_pub, device_name)`.
+4. **Sender-side fan-out**: при отправке — один envelope на каждое
+   активное устройство получателя. Мессадж → N конвертов.
+5. **Revoke**: master подписывает `UNLINK_DEVICE`, клиент, обнаруживший
+   свой `x25519_pub` в revoked — wipe'ит локальную БД (zeroize master
+   Ed25519 + delete chats).
+
+### План работ (PR-by-PR)
+
+#### PR #1 — Chain-side (backend) — _v2.2.0-alpha1_
+
+- [ ] `blockchain/types.go`: `EventLinkDevice`, `EventUnlinkDevice`
+  + payload structs `LinkDevicePayload`, `UnlinkDevicePayload`.
+- [ ] `blockchain/chain.go`: applyTx-ветки, state persistence:
+  - `prefixDevice + x25519_pub → DeviceRecord{owner, name, added_at, revoked_at?}`.
+  - Обратный индекс `prefixDevicesByOwner + master_pub → [x25519_pub, …]`.
+- [ ] Константа `MaxDevicesPerOwner = 10`.
+- [ ] Validation:
+  - Tx подписана master'ом; подпись matches `payload.Owner`.
+  - `x25519_pub` уникален в registry (не занят другим master'ом).
+  - `device_name` ≤ 64 символов; printable.
+  - При `UNLINK_DEVICE`: запись существует, owner совпадает с signer'ом.
+- [ ] HTTP: `GET /api/devices/{master_pub}` → `[{x25519_pub, device_name, added_at}, …]`,
+  фильтрует revoked.
+- [ ] В `/api/identity/{pub}` добавить поле `device_count`.
+- [ ] Unit-тесты:
+  - Happy path link + list.
+  - Unlink → list сократился.
+  - Лимит `MaxDevicesPerOwner`.
+  - Чужая подпись → reject.
+  - Duplicate x25519_pub → reject.
+- [ ] Swagger + `docs/api/devices.md`.
+
+Совместимость: старые клиенты, которые не обновили identity, продолжают
+работать по old-schema (envelope на published X25519 из identity). Sender
+fall-back'ит на identity.x25519, если `device_count == 0`.
+
+#### PR #2 — Client fan-out (mobile) — _v2.2.0-alpha2_
+
+- [ ] `lib/api.ts`: `fetchDevices(masterPub): Promise<DeviceRecord[]>`,
+  с кэшем в zustand store + инвалидацией по WS-ивенту `tx:LINK_DEVICE|UNLINK_DEVICE`.
+- [ ] `chats/[id].tsx` → `sendCore`: `Promise.all` по `devices[]`;
+  если `devices.length == 0` — fall-back на identity.x25519 (legacy path).
+- [ ] При первом старте (онбординг): если identity ещё не зарегистрирована —
+  `PUBLISH_KEY` tx + `LINK_DEVICE` tx (**этот** девайс как первый в списке).
+- [ ] UI: в chat-list tile бейдж `2/2` на своих сообщениях (доставлено
+  на N устройств получателя).
+- [ ] Тест: два клиента на одну identity, отправляем на contact — оба
+  получают.
+
+#### PR #3 — Devices screen + pairing flow (mobile + desktop) — _v2.2.0-alpha3_
+
+- [ ] Settings → **Devices**: список активных, unlink-кнопка у каждого
+  (кроме `this device`).
+- [ ] «Link new device» flow:
+  - Новое устройство генерит свой X25519, показывает QR
+    `{x25519_pub, device_name, nonce, rendezvous_id}`.
+  - Старое сканирует → Confirm → подписывает `LINK_DEVICE` tx +
+    шлёт через relay envelope `{master_ed25519_priv, recent_history}` —
+    encrypted for new device's X25519, TTL ≤ 60 сек.
+  - Новое читает envelope, сохраняет master + history, готово.
+- [ ] Self-wipe при обнаружении своего `x25519_pub` в revoked:
+  zeroize master, clear AsyncStorage/keychain, redirect на onboarding.
+
+#### PR #4 — Desktop Electron shell — _v2.2.0-rc1_
+
+См. отдельный раздел ниже.
+
+### Нерешённые вопросы
+
+- **QR-pairing UX на desktop'е**: у ноутбука камеры часто нет. Вариант:
+  master на phone шлёт invite-envelope по pre-shared secret (6-digit code,
+  вводится в обе стороны), без QR. Подумать после PR #2.
+- **History-sync backup формат**: JSON export всей ChatStorage shreds'ов?
+  Ограничение по размеру? TTL у backup-конверта? — в PR #3.
+- **Revoked-device-wipe race**: если устройство оффлайн 6 месяцев, потом
+  поднимается — первое что видит это свой revoked. Должен успеть wipe'нуться
+  **до** попытки послать tx с master-ключом. Продумать порядок bootstrap'а.
+
+---
+
+## Desktop client (Electron)
+
+Цель: 1:1 функциональный паритет с мобильным, десктопная эргономика, keyboard-first.
+
+### Архитектура
+
+- **Electron** + **React (Vite)** + **TypeScript**.
+- 80% `lib/` переиспользуется из `client-app/lib/` (api, feed, crypto, store, types).
+- Нативные модули: `electron-store` (+ `safeStorage`) для keys, `clipboard`,
+  `Notification`, `dialog.showOpenDialog`.
+- Custom title bar (frame-less), 3-panel layout.
+
+### Экраны
+
+Full design — `docs/desktop-design.md` (TODO). Sections:
+
+- **Messages** — список чатов + conversation panel. Saved Messages pinned top.
+- **Feed** — tabs (For You / Following / Trending 24h / 7d / Hashtag) +
+  post list + thread panel.
+- **Wallet** — account overview + tx history + tx detail.
+- **Contacts** — grouped list (All / Online / Blocked / Requests) + contact profile.
+- **Settings** — grouped: Node, Identity, **Devices**, Privacy, Feed, Notifications,
+  Advanced, About.
+- **Profile** (внизу nav) — self profile; чужой — в detail pane.
+- **Auth/Onboarding** — Welcome / Create / Import / Pair-with-phone (QR/code).
+
+### Стилистика (переносим)
+
+Чёрный `#000`, карточки `#0a0a0a`, бордеры `#1f1f1f`, текст `#fff`/`#8b8b8b`.
+Синий accent `#1d9bf0`, оранж warning `#f0b35a`. Синий bookmark-avatar для Saved Messages.
+
+### Не переносим
+
+Все React-Native-анимации (Pressable-animations, `scaleY: -1`, gesture-handler
+long-press). На десктопе — правый клик, hover-states, keyboard shortcuts,
+обычный scroll вместо inverted FlatList.
+
+### Global keybinds
+
+| Key | Action |
+|---|---|
+| `Ctrl/Cmd+1..5` | Переключение секций |
+| `Ctrl/Cmd+N` | Новый пост / новый контакт (контекстно) |
+| `Ctrl/Cmd+K` | Global search |
+| `Ctrl/Cmd+F` | Search в текущей list pane |
+| `Ctrl/Cmd+,` | Settings |
+| `Ctrl/Cmd+Enter` | Send (chat / publish post) |
+| `Esc` | Close modal / cancel selection |
+
+### Структура папок
+
+```
+desktop/
+├── electron/
+│   ├── main.ts          # BrowserWindow, IPC, auto-update
+│   ├── preload.ts       # contextBridge — safe API
+│   ├── menu.ts          # native menu bar
+│   └── deep-link.ts     # dchain:// protocol handler
+├── src/                 # renderer
+│   ├── App.tsx
+│   ├── shell/           # nav, status bar, title bar
+│   ├── sections/
+│   │   ├── messages/
+│   │   ├── feed/
+│   │   ├── wallet/
+│   │   ├── contacts/
+│   │   ├── settings/
+│   │   └── profile/
+│   ├── modals/
+│   ├── auth/
+│   ├── lib/             # reuse из client-app/lib
+│   └── styles/
+└── package.json
+```
+
+### План работ (отдельно, после v2.2.0-alpha3)
+
+- [ ] Boilerplate: Electron + Vite + React + TS, frame-less window, 3-panel shell.
+- [ ] Сопрягание `lib/` из client-app (заменить expo-* на Electron-эквиваленты).
+- [ ] Sections по порядку: Messages → Feed → Wallet → Contacts → Settings → Profile.
+- [ ] Multi-device pairing flow (использует v2.2.0 registry).
+- [ ] Auto-update через electron-updater или через тот же `/api/update-check`.
+- [ ] Packaging: `electron-builder` → `.dmg`, `.exe`, `.AppImage`, `.deb`.
+
+### Открытые вопросы (desktop)
+
+- **Auto-update channel**: гнать через Gitea releases (как node) или отдельный S3/Gitea-attachments?
+- **Sandbox**: desktop хранит master Ed25519 — обязательно `safeStorage` (macOS Keychain, Windows DPAPI, libsecret на Linux). На Linux без libsecret — fallback на plaintext + warning.
+- **Deep-link**: `dchain://chat/<pub>` для шаринга профилей/постов из браузера.
+
+---
+
+## Меньшие хвосты (неприоритетно)
+
+- `prev_hash mismatch` при двойной gossip-доставке — понизить до Debug уровня,
+  не пугать операторов (см. history с joiner-node bring-up).
+- `/api/network-info.peers` у seed'а возвращает `[]` если
+  `DCHAIN_ANNOUNCE` не задан — добавить fallback:
+  если announce пустой, публиковать *первый listen-addr + свой peer_id*
+  (не `127.0.0.1`), чтобы joiner'ы не упирались в `peers:[]`.
+- **Groups (3+ участников)** в чатах — тип `Contact.kind == 'group'`
+  в клиенте есть, а на backend'е не реализован. После v2.2.0, потому что
+  pairwise messaging ↔ group messaging на multi-device — это другой
+  математический слой (MLS или Sender Keys).
+- Repa как weight в selection-lider PBFT — сейчас только scoring; для
+  настоящего proof-of-reputation нужно переписать leader-rotation.

node/api_explorer.go

@@ -510,10 +510,63 @@ func apiIdentity(q ExplorerQuery) http.HandlerFunc {
 			jsonErr(w, err, 500)
 			return
 		}
+		// Multi-device (v2.2.0): stuff the active device count into the
+		// identity payload so a sender can decide upfront whether to
+		// fan out envelopes or fall back to the legacy single-X25519
+		// path (device_count == 0).
+		if q.DevicesOf != nil {
+			if devs, derr := q.DevicesOf(pubKey); derr == nil {
+				info.DeviceCount = len(devs)
+			}
+		}
 		jsonOK(w, info)
 	}
 }
 
+// apiDevices — GET /api/devices/{master_pub_or_addr}
+//
+// Returns the active (non-revoked) devices linked to a master Ed25519
+// identity. Used by senders to fan out one envelope per device. Legacy
+// identities (count=0) should be handled by the caller by falling back
+// to IdentityInfo.X25519Pub — this endpoint is strictly the new registry.
+func apiDevices(q ExplorerQuery) http.HandlerFunc {
+	return func(w http.ResponseWriter, r *http.Request) {
+		input := strings.TrimPrefix(r.URL.Path, "/api/devices/")
+		input = strings.Trim(input, "/")
+		if input == "" {
+			jsonErr(w, fmt.Errorf("master pubkey or address required"), 400)
+			return
+		}
+		if q.DevicesOf == nil {
+			jsonErr(w, fmt.Errorf("device registry not available"), 503)
+			return
+		}
+		pubKey, err := resolveAccountID(q, input)
+		if err != nil {
+			jsonErr(w, err, 404)
+			return
+		}
+		recs, err := q.DevicesOf(pubKey)
+		if err != nil {
+			jsonErr(w, err, 500)
+			return
+		}
+		out := make([]blockchain.DeviceInfo, 0, len(recs))
+		for _, rec := range recs {
+			out = append(out, blockchain.DeviceInfo{
+				X25519PubKey: rec.X25519PubKey,
+				DeviceName:   rec.DeviceName,
+				AddedAt:      rec.AddedAt,
+			})
+		}
+		jsonOK(w, map[string]any{
+			"master_pub": pubKey,
+			"count":      len(out),
+			"devices":    out,
+		})
+	}
+}
+
 func apiSubmitTx(q ExplorerQuery) http.HandlerFunc {
 	// The returned handler is wrapped in withSubmitTxGuards() by the caller:
 	// body size is capped at MaxTxRequestBytes and per-IP rate limiting is

node/api_feed.go

@@ -34,6 +34,7 @@ import (
 	"encoding/base64"
 	"encoding/hex"
 	"encoding/json"
+	"errors"
 	"fmt"
 	"log"
 	"net/http"
@@ -249,10 +250,16 @@ func feedPublish(cfg FeedConfig) http.HandlerFunc {
 		}
 		hashtags, err := cfg.Mailbox.Store(post, req.Ts)
 		if err != nil {
-			if err == relay.ErrPostTooLarge {
+			if errors.Is(err, relay.ErrPostTooLarge) {
 				jsonErr(w, err, 413)
 				return
 			}
+			if errors.Is(err, relay.ErrFeedQuotaExceeded) {
+				// 507 Insufficient Storage — the client should try
+				// another relay (or wait for TTL-driven eviction here).
+				jsonErr(w, err, 507)
+				return
+			}
 			jsonErr(w, err, 500)
 			return
 		}

node/api_routes.go

@@ -53,6 +53,10 @@ type ExplorerQuery struct {
 	NetStats         func() (blockchain.NetStats, error)
 	RegisteredRelays func() ([]blockchain.RegisteredRelayInfo, error)
 	IdentityInfo     func(pubKeyOrAddr string) (*blockchain.IdentityInfo, error)
+	// DevicesOf (multi-device v2.2.0) returns the identity's non-revoked
+	// device records. Empty slice if the identity hasn't linked any yet
+	// — senders fall back to IdentityInfo.X25519Pub for legacy clients.
+	DevicesOf        func(masterPub string) ([]blockchain.DeviceRecord, error)
 	ValidatorSet     func() ([]string, error)
 	SubmitTx         func(tx *blockchain.Transaction) error
 	// ConnectedPeers (optional) returns the local libp2p view of currently
@@ -222,6 +226,7 @@ func registerExplorerAPI(mux *http.ServeMux, q ExplorerQuery) {
 	mux.HandleFunc("/api/node/", apiNode(q))           // GET /api/node/{pubkey|DC...}
 	mux.HandleFunc("/api/relays", apiRelays(q))        // GET /api/relays
 	mux.HandleFunc("/api/identity/", apiIdentity(q))   // GET /api/identity/{pubkey|addr}
+	mux.HandleFunc("/api/devices/", apiDevices(q))     // GET /api/devices/{master_pub} — multi-device registry (v2.2.0)
 	mux.HandleFunc("/api/validators", apiValidators(q))// GET /api/validators
 	mux.HandleFunc("/api/tx", withWriteTokenGuard(withSubmitTxGuards(apiSubmitTx(q)))) // POST /api/tx (body size + per-IP rate limit + optional token gate)
 	// Live event stream (SSE) — GET /api/events

node/feed_e2e_test.go

@@ -72,7 +72,7 @@ func newFeedHarness(t *testing.T) *feedHarness {
 	if err != nil {
 		t.Fatalf("NewChain: %v", err)
 	}
-	fm, err := relay.OpenFeedMailbox(feedDir, 24*time.Hour)
+	fm, err := relay.OpenFeedMailbox(feedDir, 24*time.Hour, 0)
 	if err != nil {
 		t.Fatalf("OpenFeedMailbox: %v", err)
 	}

node/feed_twonode_test.go

@@ -81,11 +81,11 @@ func newTwoNodeHarness(t *testing.T) *twoNodeHarness {
 	if err != nil {
 		t.Fatalf("chain B: %v", err)
 	}
-	h.aMailbox, err = relay.OpenFeedMailbox(h.aFeedDir, 24*time.Hour)
+	h.aMailbox, err = relay.OpenFeedMailbox(h.aFeedDir, 24*time.Hour, 0)
 	if err != nil {
 		t.Fatalf("feed A: %v", err)
 	}
-	h.bMailbox, err = relay.OpenFeedMailbox(h.bFeedDir, 24*time.Hour)
+	h.bMailbox, err = relay.OpenFeedMailbox(h.bFeedDir, 24*time.Hour, 0)
 	if err != nil {
 		t.Fatalf("feed B: %v", err)
 	}

relay/feed_mailbox.go

@@ -97,24 +97,35 @@ type FeedPost struct {
 // ErrPostTooLarge is returned by Store when the post body exceeds MaxPostBodySize.
 var ErrPostTooLarge = errors.New("post body exceeds maximum allowed size")
 
+// ErrFeedQuotaExceeded is returned by Store when the on-disk footprint
+// (LSM + value log) plus the incoming post would exceed the operator-set
+// disk quota. Ops set this via --feed-disk-limit-mb. Zero = unlimited.
+var ErrFeedQuotaExceeded = errors.New("feed mailbox disk quota exceeded")
+
 // FeedMailbox stores feed post bodies.
 type FeedMailbox struct {
 	db         *badger.DB
 	ttl        time.Duration
+	quotaBytes int64 // 0 = unlimited
 }
 
 // NewFeedMailbox wraps an already-open Badger DB. TTL controls how long
 // post bodies live before auto-eviction (on-chain metadata persists
-// forever independently).
-func NewFeedMailbox(db *badger.DB, ttl time.Duration) *FeedMailbox {
+// forever independently). quotaBytes caps the on-disk footprint; 0 or
+// negative means unlimited.
+func NewFeedMailbox(db *badger.DB, ttl time.Duration, quotaBytes int64) *FeedMailbox {
 	if ttl <= 0 {
 		ttl = time.Duration(FeedPostDefaultTTLDays) * 24 * time.Hour
 	}
-	return &FeedMailbox{db: db, ttl: ttl}
+	if quotaBytes < 0 {
+		quotaBytes = 0
+	}
+	return &FeedMailbox{db: db, ttl: ttl, quotaBytes: quotaBytes}
 }
 
 // OpenFeedMailbox opens (or creates) a dedicated BadgerDB at dbPath.
-func OpenFeedMailbox(dbPath string, ttl time.Duration) (*FeedMailbox, error) {
+// quotaBytes caps the total on-disk footprint (LSM + vlog); 0 = unlimited.
+func OpenFeedMailbox(dbPath string, ttl time.Duration, quotaBytes int64) (*FeedMailbox, error) {
 	opts := badger.DefaultOptions(dbPath).
 		WithLogger(nil).
 		WithValueLogFileSize(128 << 20).
@@ -124,9 +135,19 @@ func OpenFeedMailbox(dbPath string, ttl time.Duration) (*FeedMailbox, error) {
 	if err != nil {
 		return nil, fmt.Errorf("open feed mailbox db: %w", err)
 	}
-	return NewFeedMailbox(db, ttl), nil
+	return NewFeedMailbox(db, ttl, quotaBytes), nil
 }
 
+// DiskUsage returns the current on-disk footprint (LSM + value log) in
+// bytes. Cheap — Badger tracks these counters internally.
+func (fm *FeedMailbox) DiskUsage() int64 {
+	lsm, vlog := fm.db.Size()
+	return lsm + vlog
+}
+
+// Quota returns the configured disk quota in bytes. 0 = unlimited.
+func (fm *FeedMailbox) Quota() int64 { return fm.quotaBytes }
+
 // Close releases the underlying Badger handle.
 func (fm *FeedMailbox) Close() error { return fm.db.Close() }
 
@@ -139,7 +160,23 @@ func (fm *FeedMailbox) Close() error { return fm.db.Close() }
 func (fm *FeedMailbox) Store(post *FeedPost, createdAt int64) ([]string, error) {
 	size := estimatePostSize(post)
 	if size > MaxPostBodySize {
-		return nil, ErrPostTooLarge
+		// Wrap the sentinel so the HTTP layer can still errors.Is() on it
+		// while the operator / client sees the actual offending numbers.
+		// This catches the common case where the client's pre-scrub
+		// estimate is below the cap but the server re-encode (quality=75
+		// JPEG) inflates past it.
+		return nil, fmt.Errorf("%w: size %d > max %d (after server scrub)",
+			ErrPostTooLarge, size, MaxPostBodySize)
+	}
+	// Disk quota: refuse new bodies once we're already over the cap.
+	// `size` is a post-body estimate, not the exact BadgerDB write-amp
+	// cost; we accept that slack — the goal is a coarse guard-rail so
+	// an operator's disk doesn't blow up unnoticed. Exceeding nodes
+	// still serve existing posts; only new Store() calls are refused.
+	if fm.quotaBytes > 0 {
+		if fm.DiskUsage()+int64(size) > fm.quotaBytes {
+			return nil, ErrFeedQuotaExceeded
+		}
 	}
 
 	post.CreatedAt = createdAt

relay/feed_mailbox_test.go

@@ -1,6 +1,7 @@
 package relay
 
 import (
+	"errors"
 	"os"
 	"testing"
 	"time"
@@ -12,7 +13,7 @@ func newTestFeedMailbox(t *testing.T) *FeedMailbox {
 	if err != nil {
 		t.Fatalf("MkdirTemp: %v", err)
 	}
-	fm, err := OpenFeedMailbox(dir, 24*time.Hour)
+	fm, err := OpenFeedMailbox(dir, 24*time.Hour, 0)
 	if err != nil {
 		_ = os.RemoveAll(dir)
 		t.Fatalf("OpenFeedMailbox: %v", err)
@@ -75,7 +76,7 @@ func TestFeedMailboxTooLarge(t *testing.T) {
 		Author:     "a",
 		Attachment: big,
 	}
-	if _, err := fm.Store(post, 0); err != ErrPostTooLarge {
+	if _, err := fm.Store(post, 0); !errors.Is(err, ErrPostTooLarge) {
 		t.Fatalf("Store huge post: got %v, want ErrPostTooLarge", err)
 	}
 }