diff --git a/CHANGELOG.md b/CHANGELOG.md
index 4a674fe..7fd1eec 100644
--- a/CHANGELOG.md
+++ b/CHANGELOG.md
@@ -5,6 +5,129 @@ All notable changes to Shade are documented in this file.
 The format is based on [Keep a Changelog](https://keepachangelog.com/en/1.1.0/),
 and this project adheres to [Semantic Versioning](https://semver.org/spec/v2.0.0.html).
 
+## [4.8.0] — 2026-05-08 — Sender-fingerprint attribution + `Inbox.start()` race fix
+
+Two unblocking changes for first-contact flows. First, the relay now
+captures the sender's signing-key fingerprint at PUT time and surfaces
+it on every downstream delivery — bridge push (`IncomingMessage.from`)
+and inbox-fetch response (`FetchedBlob.from`). Without it, an app
+receiving a prekey envelope from a never-before-seen peer cannot
+decrypt it: `shade.receive(from, env)` requires a sender address and
+the wire envelope itself doesn't authenticate the sender. The
+fingerprint is the same 8-byte hex of SHA-256(senderSigningKey) that
+`IncomingMessage.from` was already documented as carrying; the field
+just wasn't populated.
+
+Second, `Inbox.start()` no longer races register vs the first poll.
+Pre-fix, a fresh address calling `start()` saw the very first
+`/v1/inbox/{addr}/fetch` POST race the register HTTP RTT and return
+`SHADE_NOT_FOUND` — confusing 404 in DevTools, ~30s gap until the next
+scheduled poll, and inbox-fetch silently dark for the gap (bridge push
+covered for it, which is why this slipped through). `start()` now
+defers the first poll; `register()` success kicks `schedulePoll(0)`.
+
+Both reported by Prism (multi-device E2EE terminal). Wave-3 pair
+handshake is unblocked: web POSTs pair frame to PC inbox, PC's
+`onIncoming` gets `raw.from = "fp:<hex>"`, calls
+`shade.receive('fp:<hex>', env)`, parses plaintext, learns real
+address, sends paired-reply.
+
+### Added
+
+#### `@shade/inbox-server`
+- `InboxStore.putBlob({ ..., senderFp? })` — store interface accepts an
+  optional 8-byte hex fingerprint. `MemoryInboxStore`,
+  `SqliteInboxStore` (`@shade/storage-sqlite`), and `PostgresInboxStore`
+  (`@shade/storage-postgres`) all persist + return it.
+- `InboxStore.fetchBlobs(...)` rows expose `senderFp?: string`.
+  Undefined for legacy rows persisted by a pre-4.8 relay.
+- `POST /v1/inbox/:address` route computes `shortHash(senderSigningKey)`
+  after the sender's signature is verified and forwards it to
+  `store.putBlob({ ..., senderFp })`. The signature verification path
+  authorizes the same fingerprint that gets persisted — no new trust
+  surface.
+- `POST /v1/inbox/:address/fetch` response includes `from` per blob
+  when the row has a fingerprint. Absent on legacy rows.
+- Bridge endpoints (`/v1/bridge/{stream,poll,ws}`) now populate
+  `BridgeWireMessage.from` from the row's `senderFp`. The
+  `transport-bridge` wire format already accepted `from`; v4.7 just
+  never filled it.
+
+#### `@shade/inbox`
+- `FetchedBlob.from?: string` — relay-supplied sender fingerprint hint,
+  parsed from the fetch response.
+- `DecryptHandler` raw arg gains `from?: string`. Apps that ignore it
+  keep working unchanged (back-compat: the field is optional).
+
+### Fixed
+
+#### `@shade/inbox` — `Inbox.start()` register/poll race
+`start()` no longer schedules the first poll synchronously alongside
+the fire-and-forget `register()`. Instead, `register()` success kicks
+`schedulePoll(0)`, so the first poll fires after the server has
+acknowledged the address. Already-registered instances (where the
+local `this.registered` flag is true at `start()` time, e.g. after a
+restart that hydrated state) get an immediate poll as before.
+
+### Storage migrations
+
+Idempotent ALTER TABLE for live deployments:
+- **SQLite** (`@shade/storage-sqlite`): on open, the store does
+  `PRAGMA table_info(inbox_blobs)` and runs
+  `ALTER TABLE inbox_blobs ADD COLUMN sender_fp TEXT` if the column is
+  missing. Fresh databases get the column from the `CREATE TABLE IF
+  NOT EXISTS` directly.
+- **Postgres** (`@shade/storage-postgres`): `ensureInboxServerTables`
+  runs `ALTER TABLE shade_inbox_blobs ADD COLUMN IF NOT EXISTS
+  sender_fp TEXT`.
+
+Both leave existing rows with `sender_fp = NULL`. The fetch path emits
+`from` only when the column is non-empty, so legacy blobs surface as
+`from: undefined` (acceptance criterion (4): inter-version compat).
+
+### Tests
+- `packages/shade-inbox/tests/client.test.ts`:
+  - **Race fix**: spy fetch records the order of `register` and `fetch`
+    requests; first `fetch` (if any) must follow `register`. Pre-fix
+    the recording fetch threw "fetch fired before register completed
+    (race not fixed)".
+  - **Fetch attribution**: `FetchedBlob.from` matches
+    `SHA-256(senderSigningKey)[:8]` in hex.
+  - **DecryptHandler propagation**: `raw.from` arrives in the app's
+    handler.
+- `packages/shade-transport-bridge/tests/bridge.test.ts`: same
+  fingerprint regression for SSE, WS, and long-poll bridges
+  (`IncomingMessage.from` non-empty + matches the expected digest).
+- `packages/shade-storage-sqlite/tests/sqlite-inbox-store.test.ts`:
+  - senderFp round-trip through put + fetch.
+  - senderFp omitted on put → fetched row has `senderFp: undefined`.
+  - **Pre-4.8 schema migration**: open a DB seeded with a v4.7
+    `inbox_blobs` schema (no `sender_fp` column), reopen via
+    `SqliteInboxStore`, verify the legacy row survives + new writes
+    carry the new field.
+
+### Migration
+
+None required for app code. Existing handlers that ignore
+`raw.from` / `IncomingMessage.from` keep working unchanged. Apps that
+want sender-attributed first-contact:
+
+```ts
+inbox.onIncoming(async (raw) => {
+  const tentativeAddr = raw.from ? `fp:${raw.from}` : null;
+  if (!tentativeAddr) return null;            // legacy relay; drop
+  const env = decodeEnvelope(raw.ciphertext);
+  const plaintext = await shade.receive(tentativeAddr, env);
+  // pair frame announces real address; reconcile fp:<hex> → real
+  return null;
+});
+```
+
+For Prism specifically: drop the `await this.inbox.register()`
+workaround in `apps/web/src/shade/transport.ts` and
+`packages/shade-sidecar/src/transport.ts`. `inbox.start()` on 4.8+
+no longer races and the explicit pre-register is redundant.
+
 ## [4.7.0] — 2026-05-07 — Peer-presence events for instant `BroadcastChannel` revoke
 
 `BroadcastChannel.removeMember` (v4.6) is the right primitive for revoking a
diff --git a/packages/shade-cli/package.json b/packages/shade-cli/package.json
index 0616aea..4c8b846 100644
--- a/packages/shade-cli/package.json
+++ b/packages/shade-cli/package.json
@@ -1,6 +1,6 @@
 {
   "name": "@shade/cli",
-  "version": "4.7.0",
+  "version": "4.8.0",
   "type": "module",
   "main": "src/cli.ts",
   "bin": {
diff --git a/packages/shade-core/package.json b/packages/shade-core/package.json
index cf7cb20..4989a27 100644
--- a/packages/shade-core/package.json
+++ b/packages/shade-core/package.json
@@ -1,6 +1,6 @@
 {
   "name": "@shade/core",
-  "version": "4.7.0",
+  "version": "4.8.0",
   "type": "module",
   "main": "src/index.ts",
   "types": "src/index.ts",
diff --git a/packages/shade-crypto-web/package.json b/packages/shade-crypto-web/package.json
index f680924..2c2fbfc 100644
--- a/packages/shade-crypto-web/package.json
+++ b/packages/shade-crypto-web/package.json
@@ -1,6 +1,6 @@
 {
   "name": "@shade/crypto-web",
-  "version": "4.7.0",
+  "version": "4.8.0",
   "type": "module",
   "main": "src/index.ts",
   "types": "src/index.ts",
diff --git a/packages/shade-dashboard/package.json b/packages/shade-dashboard/package.json
index fa4fb76..c9042d4 100644
--- a/packages/shade-dashboard/package.json
+++ b/packages/shade-dashboard/package.json
@@ -1,6 +1,6 @@
 {
   "name": "@shade/dashboard",
-  "version": "4.7.0",
+  "version": "4.8.0",
   "type": "module",
   "scripts": {
     "dev": "vite",
diff --git a/packages/shade-files/package.json b/packages/shade-files/package.json
index 0effdc4..1823cb5 100644
--- a/packages/shade-files/package.json
+++ b/packages/shade-files/package.json
@@ -1,6 +1,6 @@
 {
   "name": "@shade/files",
-  "version": "4.7.0",
+  "version": "4.8.0",
   "type": "module",
   "main": "src/index.ts",
   "types": "src/index.ts",
diff --git a/packages/shade-inbox-server/package.json b/packages/shade-inbox-server/package.json
index 574f580..0ebbc6e 100644
--- a/packages/shade-inbox-server/package.json
+++ b/packages/shade-inbox-server/package.json
@@ -1,6 +1,6 @@
 {
   "name": "@shade/inbox-server",
-  "version": "4.7.0",
+  "version": "4.8.0",
   "type": "module",
   "main": "src/index.ts",
   "types": "src/index.ts",
diff --git a/packages/shade-inbox-server/src/bridge.ts b/packages/shade-inbox-server/src/bridge.ts
index 7a583a4..906a486 100644
--- a/packages/shade-inbox-server/src/bridge.ts
+++ b/packages/shade-inbox-server/src/bridge.ts
@@ -497,6 +497,8 @@ interface BlobRow {
   ciphertext: Uint8Array;
   receivedAt: number;
   expiresAt: number;
+  /** V4.8 — relay-captured sender fingerprint. Optional for legacy rows. */
+  senderFp?: string;
 }
 
 interface BlobWriter {
@@ -542,13 +544,26 @@ function serializeBlob(blob: BlobRow): {
   ciphertext: string;
   receivedAt: number;
   expiresAt: number;
+  from?: string;
 } {
-  return {
+  const out: {
+    msgId: string;
+    ciphertext: string;
+    receivedAt: number;
+    expiresAt: number;
+    from?: string;
+  } = {
     msgId: blob.msgId,
     ciphertext: toBase64(blob.ciphertext),
     receivedAt: blob.receivedAt,
     expiresAt: blob.expiresAt,
   };
+  // V4.8 — relay-captured sender fingerprint. The transport-bridge
+  // wire format already accepts `from`; populating it lets receivers
+  // bootstrap unknown-sender first-contact via `shade.receive('fp:<hex>',
+  // env)` without requiring an out-of-band sender hint.
+  if (blob.senderFp) out.from = blob.senderFp;
+  return out;
 }
 
 function buildPollResponse(blobs: BlobRow[], sinceFallback: number): {
diff --git a/packages/shade-inbox-server/src/memory-store.ts b/packages/shade-inbox-server/src/memory-store.ts
index bdcbaa4..74b3ffb 100644
--- a/packages/shade-inbox-server/src/memory-store.ts
+++ b/packages/shade-inbox-server/src/memory-store.ts
@@ -5,6 +5,7 @@ interface BlobRow {
   ciphertext: Uint8Array;
   receivedAt: number;
   expiresAt: number;
+  senderFp?: string;
 }
 
 /**
@@ -33,6 +34,7 @@ export class MemoryInboxStore implements InboxStore {
     msgId: string;
     ciphertext: Uint8Array;
     expiresAt: number;
+    senderFp?: string;
   }): Promise<{ created: boolean; receivedAt: number }> {
     const list = this.blobs.get(args.address) ?? [];
     const existing = list.find((r) => r.msgId === args.msgId);
@@ -41,12 +43,14 @@ export class MemoryInboxStore implements InboxStore {
     // multiple blobs land in the same millisecond.
     const receivedAt = Math.max(this.nextReceivedAt + 1, Date.now());
     this.nextReceivedAt = receivedAt;
-    list.push({
+    const row: BlobRow = {
       msgId: args.msgId,
       ciphertext: new Uint8Array(args.ciphertext),
       receivedAt,
       expiresAt: args.expiresAt,
-    });
+    };
+    if (args.senderFp !== undefined) row.senderFp = args.senderFp;
+    list.push(row);
     this.blobs.set(args.address, list);
     return { created: true, receivedAt };
   }
@@ -56,18 +60,36 @@ export class MemoryInboxStore implements InboxStore {
     sinceCursor: number;
     now: number;
     limit: number;
-  }): Promise<Array<{ msgId: string; ciphertext: Uint8Array; receivedAt: number; expiresAt: number }>> {
+  }): Promise<
+    Array<{
+      msgId: string;
+      ciphertext: Uint8Array;
+      receivedAt: number;
+      expiresAt: number;
+      senderFp?: string;
+    }>
+  > {
     const list = this.blobs.get(args.address) ?? [];
     return list
       .filter((r) => r.receivedAt > args.sinceCursor && r.expiresAt > args.now)
       .sort((a, b) => a.receivedAt - b.receivedAt)
       .slice(0, args.limit)
-      .map((r) => ({
-        msgId: r.msgId,
-        ciphertext: new Uint8Array(r.ciphertext),
-        receivedAt: r.receivedAt,
-        expiresAt: r.expiresAt,
-      }));
+      .map((r) => {
+        const out: {
+          msgId: string;
+          ciphertext: Uint8Array;
+          receivedAt: number;
+          expiresAt: number;
+          senderFp?: string;
+        } = {
+          msgId: r.msgId,
+          ciphertext: new Uint8Array(r.ciphertext),
+          receivedAt: r.receivedAt,
+          expiresAt: r.expiresAt,
+        };
+        if (r.senderFp !== undefined) out.senderFp = r.senderFp;
+        return out;
+      });
   }
 
   async deleteBlob(address: string, msgId: string): Promise<boolean> {
diff --git a/packages/shade-inbox-server/src/routes.ts b/packages/shade-inbox-server/src/routes.ts
index e2de577..042c0bd 100644
--- a/packages/shade-inbox-server/src/routes.ts
+++ b/packages/shade-inbox-server/src/routes.ts
@@ -255,11 +255,19 @@ export function createInboxRoutes(
       );
     }
 
+    // V4.8: capture sender fingerprint at PUT time. The sender's
+    // signing key was just verified for this request, so the fingerprint
+    // is bound to the same authentication path that authorized the
+    // store. Surfaced on bridge push + inbox-fetch responses to
+    // bootstrap unknown-sender first-contact (X3DH pair handshake).
+    const senderFp = await shortHash(senderKey);
+
     const result = await store.putBlob({
       address,
       msgId,
       ciphertext: ctBytes,
       expiresAt,
+      senderFp,
     });
     if (result.created) {
       events?.emit('inbox.blob_stored', {
@@ -319,12 +327,22 @@ export function createInboxRoutes(
     let bytes = 0;
     const blobs = rows.map((r) => {
       bytes += r.ciphertext.length;
-      return {
+      const out: {
+        msgId: string;
+        ciphertext: string;
+        receivedAt: number;
+        expiresAt: number;
+        from?: string;
+      } = {
         msgId: r.msgId,
         ciphertext: toBase64(r.ciphertext),
         receivedAt: r.receivedAt,
         expiresAt: r.expiresAt,
       };
+      // V4.8: surface sender fingerprint when present. Empty for blobs
+      // persisted by a pre-4.8 relay that didn't track sender provenance.
+      if (r.senderFp) out.from = r.senderFp;
+      return out;
     });
     const nextCursor = rows.length > 0 ? rows[rows.length - 1]!.receivedAt : sinceCursor;
 
diff --git a/packages/shade-inbox-server/src/store.ts b/packages/shade-inbox-server/src/store.ts
index 7d58707..279e7b8 100644
--- a/packages/shade-inbox-server/src/store.ts
+++ b/packages/shade-inbox-server/src/store.ts
@@ -36,12 +36,20 @@ export interface InboxStore {
    * **Idempotent**: if a row already exists for `(address, msgId)` the
    * implementation MUST return `{ created: false }` and leave the existing
    * row untouched. A fresh insert returns `{ created: true, receivedAt }`.
+   *
+   * `senderFp` (V4.8+) is the 8-byte hex of SHA-256(senderSigningKey)
+   * — captured at PUT time when the relay verified the sender's
+   * signature. Optional so legacy 4.7 callers compile, but populated by
+   * `createInboxRoutes` from 4.8 onward and surfaced on bridge push +
+   * inbox-fetch responses to bootstrap unknown-sender first-contact
+   * (X3DH pair handshake).
    */
   putBlob(args: {
     address: string;
     msgId: string;
     ciphertext: Uint8Array;
     expiresAt: number;
+    senderFp?: string;
   }): Promise<{ created: boolean; receivedAt: number }>;
 
   /**
@@ -57,7 +65,20 @@ export interface InboxStore {
     sinceCursor: number;
     now: number;
     limit: number;
-  }): Promise<Array<{ msgId: string; ciphertext: Uint8Array; receivedAt: number; expiresAt: number }>>;
+  }): Promise<
+    Array<{
+      msgId: string;
+      ciphertext: Uint8Array;
+      receivedAt: number;
+      expiresAt: number;
+      /**
+       * Sender fingerprint — 8-byte hex of SHA-256(senderSigningKey)
+       * captured at PUT time. Empty/undefined for blobs persisted by a
+       * pre-4.8 relay that didn't track sender provenance.
+       */
+      senderFp?: string;
+    }>
+  >;
 
   /**
    * Delete a single blob by `(address, msgId)`. Returns true if a row was
diff --git a/packages/shade-inbox/package.json b/packages/shade-inbox/package.json
index bd92d75..b34930d 100644
--- a/packages/shade-inbox/package.json
+++ b/packages/shade-inbox/package.json
@@ -1,6 +1,6 @@
 {
   "name": "@shade/inbox",
-  "version": "4.7.0",
+  "version": "4.8.0",
   "type": "module",
   "main": "src/index.ts",
   "types": "src/index.ts",
diff --git a/packages/shade-inbox/src/client.ts b/packages/shade-inbox/src/client.ts
index aef5f1e..4ade84b 100644
--- a/packages/shade-inbox/src/client.ts
+++ b/packages/shade-inbox/src/client.ts
@@ -40,6 +40,16 @@ export interface FetchedBlob {
   receivedAt: number;
   /** Absolute expiry time (ms since epoch) reported by the server. */
   expiresAt: number;
+  /**
+   * Sender fingerprint — 8-byte hex of SHA-256(senderSigningKey),
+   * captured by the relay at PUT time when the sender's signature was
+   * verified. Empty/undefined when the relay is pre-4.8 or the blob
+   * predates sender-fingerprint tracking. Use as an unknown-sender
+   * bootstrap label (`fp:<hex>`) for X3DH first-contact; the
+   * authoritative sender identity is recovered post-decrypt from the
+   * envelope itself, so `from` is a hint, not a trust anchor.
+   */
+  from?: string;
 }
 
 export interface FetchResult {
@@ -151,12 +161,18 @@ export class InboxClient {
     );
     const blobs = Array.isArray(json.blobs) ? json.blobs : [];
     return {
-      blobs: blobs.map((b: any) => ({
-        msgId: String(b.msgId),
-        ciphertext: fromBase64(String(b.ciphertext)),
-        receivedAt: Number(b.receivedAt),
-        expiresAt: Number(b.expiresAt),
-      })),
+      blobs: blobs.map((b: any): FetchedBlob => {
+        const out: FetchedBlob = {
+          msgId: String(b.msgId),
+          ciphertext: fromBase64(String(b.ciphertext)),
+          receivedAt: Number(b.receivedAt),
+          expiresAt: Number(b.expiresAt),
+        };
+        // V4.8 — relay-supplied sender fingerprint hint. Optional; absent
+        // on pre-4.8 relays or for blobs persisted before tracking landed.
+        if (typeof b.from === 'string' && b.from.length > 0) out.from = b.from;
+        return out;
+      }),
       cursor: Number(json.cursor ?? sinceCursor),
       hasMore: Boolean(json.hasMore),
     };
diff --git a/packages/shade-inbox/src/inbox.ts b/packages/shade-inbox/src/inbox.ts
index 8597458..0f7fadd 100644
--- a/packages/shade-inbox/src/inbox.ts
+++ b/packages/shade-inbox/src/inbox.ts
@@ -16,9 +16,20 @@ import { InboxClientEvents, type InboxClientListener } from './events.js';
  * decrypt path it owns) and either return a sender-hint for telemetry
  * (the address the SDK extracted, or `null`) or throw to keep the blob
  * on the server for a later retry.
+ *
+ * V4.8: `raw.from` is the relay-captured sender fingerprint (8-byte hex
+ * of SHA-256 over the sender's signing key). Empty when the relay is
+ * pre-4.8 or didn't track the sender. Use it as the `fp:<hex>` bootstrap
+ * label for X3DH first-contact handshakes.
  */
 export type DecryptHandler = (
-  raw: { msgId: string; ciphertext: Uint8Array; receivedAt: number; expiresAt: number },
+  raw: {
+    msgId: string;
+    ciphertext: Uint8Array;
+    receivedAt: number;
+    expiresAt: number;
+    from?: string;
+  },
 ) => Promise<string | null | undefined> | string | null | undefined;
 
 export interface InboxOptions {
@@ -149,6 +160,14 @@ export class Inbox {
       signingKey: this.options.signingPublicKey,
     });
     this.registered = true;
+    // V4.8: gate the first poll on register success. `start()` calls
+    // `register()` fire-and-forget; without this kick, the very first
+    // `pollOnce()` (scheduled synchronously alongside register) would
+    // race the register HTTP RTT and return SHADE_NOT_FOUND. The
+    // pollOnce() guard skips polls until `registered === true`; this
+    // immediate schedule ensures we don't wait the full pollIntervalMs
+    // for the next attempt once register lands.
+    if (this.started) this.schedulePoll(0);
   }
 
   /** Drop the address from the server. Local queue/cursor are preserved. */
@@ -217,7 +236,11 @@ export class Inbox {
       this.scheduleRegisterRetry();
     });
     this.scheduleFlush();
-    this.schedulePoll(0);
+    // V4.8: do NOT schedule the first poll synchronously. `register()`
+    // success kicks `schedulePoll(0)` so the first poll fires after the
+    // server has acknowledged the address. Pre-fix this raced register
+    // and burned a 404 on every fresh-address `start()`.
+    if (this.registered) this.schedulePoll(0);
   }
 
   /** Stop background timers. Pending entries remain in the queue. */
@@ -375,12 +398,20 @@ export class Inbox {
 
     let senderHint: string | null = null;
     try {
-      const result = await this.incomingHandler({
+      const raw: {
+        msgId: string;
+        ciphertext: Uint8Array;
+        receivedAt: number;
+        expiresAt: number;
+        from?: string;
+      } = {
         msgId: blob.msgId,
         ciphertext: blob.ciphertext,
         receivedAt: blob.receivedAt,
         expiresAt: blob.expiresAt,
-      });
+      };
+      if (blob.from !== undefined) raw.from = blob.from;
+      const result = await this.incomingHandler(raw);
       senderHint = result ?? null;
     } catch (err) {
       this.events.emit('inbox.message_decrypt_failed', {
diff --git a/packages/shade-inbox/tests/client.test.ts b/packages/shade-inbox/tests/client.test.ts
index e071cbf..d86e3cb 100644
--- a/packages/shade-inbox/tests/client.test.ts
+++ b/packages/shade-inbox/tests/client.test.ts
@@ -326,3 +326,150 @@ describe('InboxClient — default fetch is bound to globalThis', () => {
     }
   });
 });
+
+describe('Inbox.start() — fresh-address register/poll race (V4.8)', () => {
+  // Regression: pre-4.8 `start()` called `register()` fire-and-forget AND
+  // `schedulePoll(0)` synchronously, so the first poll often beat the
+  // register HTTP RTT and got SHADE_NOT_FOUND on a fresh address. Fix:
+  // start() defers the first poll; register() success kicks it.
+  test('fresh address: no fetch fires before register completes', async () => {
+    const store = new MemoryInboxStore();
+    const app = createInboxServer({ crypto, store, disableRateLimit: true });
+    const alice = await makeIdentity();
+
+    // Order observed by the server: must be register-then-fetch, never
+    // fetch-then-register.
+    const calls: Array<'register' | 'fetch' | 'put'> = [];
+    let registerArrived = false;
+    const recordingFetch: typeof fetch = (async (input, init) => {
+      const u =
+        typeof input === 'string'
+          ? input
+          : input instanceof URL
+            ? input.toString()
+            : (input as Request).url;
+      if (u.includes('/v1/inbox/register')) {
+        calls.push('register');
+        // Hold register for a tick to widen the race window.
+        await new Promise((r) => setTimeout(r, 25));
+        registerArrived = true;
+      } else if (u.endsWith('/fetch')) {
+        // Any fetch arriving before register is the race we're guarding
+        // against.
+        if (!registerArrived) {
+          throw new Error('fetch fired before register completed (race not fixed)');
+        }
+        calls.push('fetch');
+      } else if (u.includes('/v1/inbox/')) {
+        calls.push('put');
+      }
+      return honoFetch(app)(input, init);
+    }) as typeof fetch;
+
+    const inbox = new Inbox({
+      baseUrl: 'http://localhost',
+      ownAddress: 'alice',
+      crypto,
+      signingPrivateKey: alice.signingPrivateKey,
+      signingPublicKey: alice.signingPublicKey,
+      pollIntervalMs: 30_000, // Long enough that only register's kick triggers.
+      fetch: recordingFetch,
+    });
+    inbox.onIncoming(() => null);
+    inbox.start();
+
+    // Wait until register has completed and the success-kick poll lands.
+    await new Promise((r) => setTimeout(r, 100));
+    inbox.stop();
+
+    expect(calls[0]).toBe('register');
+    // First fetch (if any) must be after register.
+    const firstFetchIdx = calls.indexOf('fetch');
+    if (firstFetchIdx !== -1) {
+      expect(firstFetchIdx).toBeGreaterThan(calls.indexOf('register'));
+    }
+  });
+});
+
+describe('FetchedBlob.from — relay-supplied sender fingerprint (V4.8)', () => {
+  test('inbox-fetch response carries from = 8-byte hex of SHA-256(senderSigningKey)', async () => {
+    const store = new MemoryInboxStore();
+    const app = createInboxServer({ crypto, store, disableRateLimit: true });
+    const bob = await makeIdentity();
+    const alice = await makeIdentity();
+
+    const bobClient = new InboxClient({
+      baseUrl: 'http://localhost',
+      crypto,
+      signingPrivateKey: bob.signingPrivateKey,
+      fetch: honoFetch(app),
+    });
+    const aliceClient = new InboxClient({
+      baseUrl: 'http://localhost',
+      crypto,
+      signingPrivateKey: alice.signingPrivateKey,
+      fetch: honoFetch(app),
+    });
+
+    await bobClient.register({ address: 'bob', signingKey: bob.signingPublicKey });
+    await aliceClient.put({
+      recipientAddress: 'bob',
+      senderSigningKey: alice.signingPublicKey,
+      envelope: randBytes(64),
+    });
+
+    const fetched = await bobClient.fetch({ address: 'bob' });
+    expect(fetched.blobs.length).toBe(1);
+    const fp = fetched.blobs[0]!.from;
+    expect(fp).toBeDefined();
+    expect(fp).toMatch(/^[0-9a-f]{16}$/);
+
+    // Must be reproducible: SHA-256(alice.signingPublicKey) → first 8 bytes hex.
+    const digest = await globalThis.crypto.subtle.digest(
+      'SHA-256',
+      alice.signingPublicKey as unknown as ArrayBuffer,
+    );
+    const expected = Array.from(new Uint8Array(digest).slice(0, 8), (b) =>
+      b.toString(16).padStart(2, '0'),
+    ).join('');
+    expect(fp).toBe(expected);
+  });
+
+  test('DecryptHandler raw arg propagates from to the app', async () => {
+    const store = new MemoryInboxStore();
+    const app = createInboxServer({ crypto, store, disableRateLimit: true });
+    const bob = await makeIdentity();
+    const alice = await makeIdentity();
+
+    const aliceClient = new InboxClient({
+      baseUrl: 'http://localhost',
+      crypto,
+      signingPrivateKey: alice.signingPrivateKey,
+      fetch: honoFetch(app),
+    });
+    const bobInbox = new Inbox({
+      baseUrl: 'http://localhost',
+      ownAddress: 'bob',
+      crypto,
+      signingPrivateKey: bob.signingPrivateKey,
+      signingPublicKey: bob.signingPublicKey,
+      pollIntervalMs: 0,
+      fetch: honoFetch(app),
+    });
+
+    await bobInbox.register();
+    await aliceClient.put({
+      recipientAddress: 'bob',
+      senderSigningKey: alice.signingPublicKey,
+      envelope: randBytes(40),
+    });
+
+    let observed: string | undefined = undefined;
+    bobInbox.onIncoming((raw) => {
+      observed = raw.from;
+      return null;
+    });
+    await bobInbox.tick();
+    expect(observed).toMatch(/^[0-9a-f]{16}$/);
+  });
+});
diff --git a/packages/shade-key-transparency/package.json b/packages/shade-key-transparency/package.json
index 6c7a994..527e820 100644
--- a/packages/shade-key-transparency/package.json
+++ b/packages/shade-key-transparency/package.json
@@ -1,6 +1,6 @@
 {
   "name": "@shade/key-transparency",
-  "version": "4.7.0",
+  "version": "4.8.0",
   "type": "module",
   "main": "src/index.ts",
   "types": "src/index.ts",
diff --git a/packages/shade-keychain/package.json b/packages/shade-keychain/package.json
index 4fc805b..5c4b2e9 100644
--- a/packages/shade-keychain/package.json
+++ b/packages/shade-keychain/package.json
@@ -1,6 +1,6 @@
 {
   "name": "@shade/keychain",
-  "version": "4.7.0",
+  "version": "4.8.0",
   "type": "module",
   "main": "src/index.ts",
   "types": "src/index.ts",
diff --git a/packages/shade-observability/package.json b/packages/shade-observability/package.json
index 1b8622b..598c1c2 100644
--- a/packages/shade-observability/package.json
+++ b/packages/shade-observability/package.json
@@ -1,6 +1,6 @@
 {
   "name": "@shade/observability",
-  "version": "4.7.0",
+  "version": "4.8.0",
   "type": "module",
   "main": "src/index.ts",
   "types": "src/index.ts",
diff --git a/packages/shade-observer/package.json b/packages/shade-observer/package.json
index 325dacd..8ea4c67 100644
--- a/packages/shade-observer/package.json
+++ b/packages/shade-observer/package.json
@@ -1,6 +1,6 @@
 {
   "name": "@shade/observer",
-  "version": "4.7.0",
+  "version": "4.8.0",
   "type": "module",
   "main": "src/index.ts",
   "types": "src/index.ts",
diff --git a/packages/shade-proto/package.json b/packages/shade-proto/package.json
index 9afe2b1..3e165af 100644
--- a/packages/shade-proto/package.json
+++ b/packages/shade-proto/package.json
@@ -1,6 +1,6 @@
 {
   "name": "@shade/proto",
-  "version": "4.7.0",
+  "version": "4.8.0",
   "type": "module",
   "main": "src/index.ts",
   "types": "src/index.ts",
diff --git a/packages/shade-recovery/package.json b/packages/shade-recovery/package.json
index e8e1604..3afa9a5 100644
--- a/packages/shade-recovery/package.json
+++ b/packages/shade-recovery/package.json
@@ -1,6 +1,6 @@
 {
   "name": "@shade/recovery",
-  "version": "4.7.0",
+  "version": "4.8.0",
   "type": "module",
   "main": "src/index.ts",
   "types": "src/index.ts",
diff --git a/packages/shade-sdk/package.json b/packages/shade-sdk/package.json
index a00b72f..66edf15 100644
--- a/packages/shade-sdk/package.json
+++ b/packages/shade-sdk/package.json
@@ -1,6 +1,6 @@
 {
   "name": "@shade/sdk",
-  "version": "4.7.0",
+  "version": "4.8.0",
   "type": "module",
   "main": "src/index.ts",
   "types": "src/index.ts",
diff --git a/packages/shade-server/package.json b/packages/shade-server/package.json
index 30ce969..c02735e 100644
--- a/packages/shade-server/package.json
+++ b/packages/shade-server/package.json
@@ -1,6 +1,6 @@
 {
   "name": "@shade/server",
-  "version": "4.7.0",
+  "version": "4.8.0",
   "type": "module",
   "main": "src/index.ts",
   "types": "src/index.ts",
diff --git a/packages/shade-storage-encrypted/package.json b/packages/shade-storage-encrypted/package.json
index f0903f4..0aa3b80 100644
--- a/packages/shade-storage-encrypted/package.json
+++ b/packages/shade-storage-encrypted/package.json
@@ -1,6 +1,6 @@
 {
   "name": "@shade/storage-encrypted",
-  "version": "4.7.0",
+  "version": "4.8.0",
   "type": "module",
   "main": "src/index.ts",
   "types": "src/index.ts",
diff --git a/packages/shade-storage-indexeddb/package.json b/packages/shade-storage-indexeddb/package.json
index a3472d3..10f2e00 100644
--- a/packages/shade-storage-indexeddb/package.json
+++ b/packages/shade-storage-indexeddb/package.json
@@ -1,6 +1,6 @@
 {
   "name": "@shade/storage-indexeddb",
-  "version": "4.7.0",
+  "version": "4.8.0",
   "type": "module",
   "main": "src/index.ts",
   "types": "src/index.ts",
diff --git a/packages/shade-storage-postgres/package.json b/packages/shade-storage-postgres/package.json
index aa0fec0..177934e 100644
--- a/packages/shade-storage-postgres/package.json
+++ b/packages/shade-storage-postgres/package.json
@@ -1,6 +1,6 @@
 {
   "name": "@shade/storage-postgres",
-  "version": "4.7.0",
+  "version": "4.8.0",
   "type": "module",
   "main": "src/index.ts",
   "types": "src/index.ts",
diff --git a/packages/shade-storage-postgres/src/ensure-tables.ts b/packages/shade-storage-postgres/src/ensure-tables.ts
index 9ad9fa9..33c5664 100644
--- a/packages/shade-storage-postgres/src/ensure-tables.ts
+++ b/packages/shade-storage-postgres/src/ensure-tables.ts
@@ -223,9 +223,16 @@ export async function ensureInboxServerTables(sql: Sql): Promise<void> {
       ciphertext  TEXT NOT NULL,
       received_at BIGINT NOT NULL,
       expires_at  BIGINT NOT NULL,
+      sender_fp   TEXT,
       PRIMARY KEY (address, msg_id)
     )
   `;
+  // V4.8 — sender fingerprint column. Idempotent ADD COLUMN for live
+  // databases that came up under a 4.7-or-earlier schema.
+  await sql`
+    ALTER TABLE shade_inbox_blobs
+    ADD COLUMN IF NOT EXISTS sender_fp TEXT
+  `;
   await sql`
     CREATE INDEX IF NOT EXISTS shade_inbox_addr_expires_idx
     ON shade_inbox_blobs(address, expires_at)
diff --git a/packages/shade-storage-postgres/src/postgres-inbox-store.ts b/packages/shade-storage-postgres/src/postgres-inbox-store.ts
index e25d8f1..81c4a8e 100644
--- a/packages/shade-storage-postgres/src/postgres-inbox-store.ts
+++ b/packages/shade-storage-postgres/src/postgres-inbox-store.ts
@@ -56,18 +56,20 @@ export class PostgresInboxStore implements InboxStore {
     msgId: string;
     ciphertext: Uint8Array;
     expiresAt: number;
+    senderFp?: string;
   }): Promise<{ created: boolean; receivedAt: number }> {
     // ON CONFLICT DO NOTHING + RETURNING keeps it idempotent and atomic.
     // When a row already exists, we look up its received_at in a follow-up
     // SELECT.
     const inserted = await this.sql<Array<{ received_at: string }>>`
-      INSERT INTO shade_inbox_blobs (address, msg_id, ciphertext, received_at, expires_at)
+      INSERT INTO shade_inbox_blobs (address, msg_id, ciphertext, received_at, expires_at, sender_fp)
       VALUES (
         ${args.address},
         ${args.msgId},
         ${toBase64(args.ciphertext)},
         nextval('shade_inbox_seq'),
-        ${args.expiresAt}
+        ${args.expiresAt},
+        ${args.senderFp ?? null}
       )
       ON CONFLICT (address, msg_id) DO NOTHING
       RETURNING received_at::text
@@ -90,14 +92,23 @@ export class PostgresInboxStore implements InboxStore {
     sinceCursor: number;
     now: number;
     limit: number;
-  }): Promise<Array<{ msgId: string; ciphertext: Uint8Array; receivedAt: number; expiresAt: number }>> {
+  }): Promise<
+    Array<{
+      msgId: string;
+      ciphertext: Uint8Array;
+      receivedAt: number;
+      expiresAt: number;
+      senderFp?: string;
+    }>
+  > {
     const rows = await this.sql<Array<{
       msg_id: string;
       ciphertext: string;
       received_at: string;
       expires_at: string;
+      sender_fp: string | null;
     }>>`
-      SELECT msg_id, ciphertext, received_at::text, expires_at::text
+      SELECT msg_id, ciphertext, received_at::text, expires_at::text, sender_fp
       FROM shade_inbox_blobs
       WHERE address = ${args.address}
         AND received_at > ${args.sinceCursor}
@@ -105,12 +116,22 @@ export class PostgresInboxStore implements InboxStore {
       ORDER BY received_at ASC
       LIMIT ${args.limit}
     `;
-    return rows.map((r) => ({
-      msgId: r.msg_id,
-      ciphertext: fromBase64(r.ciphertext),
-      receivedAt: parseInt(r.received_at, 10),
-      expiresAt: parseInt(r.expires_at, 10),
-    }));
+    return rows.map((r) => {
+      const out: {
+        msgId: string;
+        ciphertext: Uint8Array;
+        receivedAt: number;
+        expiresAt: number;
+        senderFp?: string;
+      } = {
+        msgId: r.msg_id,
+        ciphertext: fromBase64(r.ciphertext),
+        receivedAt: parseInt(r.received_at, 10),
+        expiresAt: parseInt(r.expires_at, 10),
+      };
+      if (r.sender_fp) out.senderFp = r.sender_fp;
+      return out;
+    });
   }
 
   async deleteBlob(address: string, msgId: string): Promise<boolean> {
diff --git a/packages/shade-storage-sqlite/package.json b/packages/shade-storage-sqlite/package.json
index 3380e01..033d6dd 100644
--- a/packages/shade-storage-sqlite/package.json
+++ b/packages/shade-storage-sqlite/package.json
@@ -1,6 +1,6 @@
 {
   "name": "@shade/storage-sqlite",
-  "version": "4.7.0",
+  "version": "4.8.0",
   "type": "module",
   "main": "src/index.ts",
   "types": "src/index.ts",
diff --git a/packages/shade-storage-sqlite/src/sqlite-inbox-store.ts b/packages/shade-storage-sqlite/src/sqlite-inbox-store.ts
index e9a744f..9276e98 100644
--- a/packages/shade-storage-sqlite/src/sqlite-inbox-store.ts
+++ b/packages/shade-storage-sqlite/src/sqlite-inbox-store.ts
@@ -53,6 +53,7 @@ export class SqliteInboxStore implements InboxStore {
         ciphertext  TEXT NOT NULL,
         received_at INTEGER NOT NULL,
         expires_at  INTEGER NOT NULL,
+        sender_fp   TEXT,
         PRIMARY KEY (address, msg_id)
       );
       CREATE INDEX IF NOT EXISTS idx_inbox_addr_expires
@@ -62,6 +63,14 @@ export class SqliteInboxStore implements InboxStore {
       CREATE INDEX IF NOT EXISTS idx_inbox_expires
         ON inbox_blobs(expires_at);
     `);
+    // V4.8 — sender fingerprint column. Idempotent ALTER for live
+    // databases that came up under a 4.7-or-earlier schema.
+    const cols = this.db
+      .prepare(`PRAGMA table_info(inbox_blobs)`)
+      .all() as Array<{ name: string }>;
+    if (!cols.some((c) => c.name === 'sender_fp')) {
+      this.db.exec(`ALTER TABLE inbox_blobs ADD COLUMN sender_fp TEXT`);
+    }
   }
 
   private prepareStatements() {
@@ -73,13 +82,13 @@ export class SqliteInboxStore implements InboxStore {
       deleteOwner: this.db.prepare('DELETE FROM inbox_owners WHERE address = ?'),
       deleteOwnerBlobs: this.db.prepare('DELETE FROM inbox_blobs WHERE address = ?'),
       insertBlob: this.db.prepare(
-        'INSERT INTO inbox_blobs (address, msg_id, ciphertext, received_at, expires_at) VALUES (?, ?, ?, ?, ?)',
+        'INSERT INTO inbox_blobs (address, msg_id, ciphertext, received_at, expires_at, sender_fp) VALUES (?, ?, ?, ?, ?, ?)',
       ),
       findBlob: this.db.prepare(
         'SELECT received_at FROM inbox_blobs WHERE address = ? AND msg_id = ?',
       ),
       fetchSince: this.db.prepare(
-        `SELECT msg_id, ciphertext, received_at, expires_at
+        `SELECT msg_id, ciphertext, received_at, expires_at, sender_fp
          FROM inbox_blobs
          WHERE address = ? AND received_at > ? AND expires_at > ?
          ORDER BY received_at ASC
@@ -124,6 +133,7 @@ export class SqliteInboxStore implements InboxStore {
     msgId: string;
     ciphertext: Uint8Array;
     expiresAt: number;
+    senderFp?: string;
   }): Promise<{ created: boolean; receivedAt: number }> {
     const existing = this.stmts.findBlob.get(args.address, args.msgId) as
       | { received_at: number }
@@ -139,6 +149,7 @@ export class SqliteInboxStore implements InboxStore {
       toBase64(args.ciphertext),
       receivedAt,
       args.expiresAt,
+      args.senderFp ?? null,
     );
     return { created: true, receivedAt };
   }
@@ -148,19 +159,43 @@ export class SqliteInboxStore implements InboxStore {
     sinceCursor: number;
     now: number;
     limit: number;
-  }): Promise<Array<{ msgId: string; ciphertext: Uint8Array; receivedAt: number; expiresAt: number }>> {
+  }): Promise<
+    Array<{
+      msgId: string;
+      ciphertext: Uint8Array;
+      receivedAt: number;
+      expiresAt: number;
+      senderFp?: string;
+    }>
+  > {
     const rows = this.stmts.fetchSince.all(
       args.address,
       args.sinceCursor,
       args.now,
       args.limit,
-    ) as Array<{ msg_id: string; ciphertext: string; received_at: number; expires_at: number }>;
-    return rows.map((r) => ({
-      msgId: r.msg_id,
-      ciphertext: fromBase64(r.ciphertext),
-      receivedAt: r.received_at,
-      expiresAt: r.expires_at,
-    }));
+    ) as Array<{
+      msg_id: string;
+      ciphertext: string;
+      received_at: number;
+      expires_at: number;
+      sender_fp: string | null;
+    }>;
+    return rows.map((r) => {
+      const out: {
+        msgId: string;
+        ciphertext: Uint8Array;
+        receivedAt: number;
+        expiresAt: number;
+        senderFp?: string;
+      } = {
+        msgId: r.msg_id,
+        ciphertext: fromBase64(r.ciphertext),
+        receivedAt: r.received_at,
+        expiresAt: r.expires_at,
+      };
+      if (r.sender_fp) out.senderFp = r.sender_fp;
+      return out;
+    });
   }
 
   async deleteBlob(address: string, msgId: string): Promise<boolean> {
diff --git a/packages/shade-storage-sqlite/tests/sqlite-inbox-store.test.ts b/packages/shade-storage-sqlite/tests/sqlite-inbox-store.test.ts
index 6a4d047..fd8fe7b 100644
--- a/packages/shade-storage-sqlite/tests/sqlite-inbox-store.test.ts
+++ b/packages/shade-storage-sqlite/tests/sqlite-inbox-store.test.ts
@@ -178,6 +178,104 @@ describe('SqliteInboxStore', () => {
     expect(blobs.length).toBe(0);
   });
 
+  test('senderFp round-trips through put + fetch (V4.8)', async () => {
+    const ct = randBytes(40);
+    const fp = '0123456789abcdef';
+    await store.putBlob({
+      address: 'bob',
+      msgId: 'a'.repeat(64),
+      ciphertext: ct,
+      expiresAt: Date.now() + 60_000,
+      senderFp: fp,
+    });
+    const blobs = await store.fetchBlobs({
+      address: 'bob',
+      sinceCursor: 0,
+      now: Date.now(),
+      limit: 10,
+    });
+    expect(blobs.length).toBe(1);
+    expect(blobs[0]!.senderFp).toBe(fp);
+  });
+
+  test('senderFp omitted on put → fetched row has senderFp undefined (V4.8 backward-compat)', async () => {
+    const ct = randBytes(40);
+    await store.putBlob({
+      address: 'bob',
+      msgId: 'b'.repeat(64),
+      ciphertext: ct,
+      expiresAt: Date.now() + 60_000,
+    });
+    const blobs = await store.fetchBlobs({
+      address: 'bob',
+      sinceCursor: 0,
+      now: Date.now(),
+      limit: 10,
+    });
+    expect(blobs.length).toBe(1);
+    expect(blobs[0]!.senderFp).toBeUndefined();
+  });
+
+  test('ALTER TABLE migration adds sender_fp to a pre-4.8 schema (V4.8)', async () => {
+    // Reproduce a pre-4.8 schema in a fresh DB, then reopen via
+    // SqliteInboxStore which should run the idempotent ALTER without
+    // dropping the existing rows.
+    store.close();
+    try {
+      unlinkSync(dbPath);
+    } catch {}
+    try {
+      unlinkSync(dbPath + '-wal');
+    } catch {}
+    try {
+      unlinkSync(dbPath + '-shm');
+    } catch {}
+
+    const { Database } = await import('bun:sqlite');
+    const legacy = new Database(dbPath, { create: true });
+    legacy.exec(`
+      CREATE TABLE inbox_blobs (
+        address     TEXT NOT NULL,
+        msg_id      TEXT NOT NULL,
+        ciphertext  TEXT NOT NULL,
+        received_at INTEGER NOT NULL,
+        expires_at  INTEGER NOT NULL,
+        PRIMARY KEY (address, msg_id)
+      );
+    `);
+    legacy.prepare(
+      'INSERT INTO inbox_blobs (address, msg_id, ciphertext, received_at, expires_at) VALUES (?, ?, ?, ?, ?)',
+    ).run('bob', 'c'.repeat(64), 'AAAA', Date.now(), Date.now() + 60_000);
+    legacy.close();
+
+    store = new SqliteInboxStore(dbPath);
+    const blobs = await store.fetchBlobs({
+      address: 'bob',
+      sinceCursor: 0,
+      now: Date.now(),
+      limit: 10,
+    });
+    expect(blobs.length).toBe(1);
+    expect(blobs[0]!.senderFp).toBeUndefined();
+
+    // New writes after migration carry senderFp.
+    await store.putBlob({
+      address: 'bob',
+      msgId: 'd'.repeat(64),
+      ciphertext: randBytes(8),
+      expiresAt: Date.now() + 60_000,
+      senderFp: 'feedfacedeadbeef',
+    });
+    const after = await store.fetchBlobs({
+      address: 'bob',
+      sinceCursor: 0,
+      now: Date.now(),
+      limit: 10,
+    });
+    const newer = after.find((b) => b.msgId === 'd'.repeat(64));
+    expect(newer?.senderFp).toBe('feedfacedeadbeef');
+  });
+
   test('countBlobs ignores expired entries', async () => {
     const now = Date.now();
     await store.putBlob({
diff --git a/packages/shade-streams/package.json b/packages/shade-streams/package.json
index cb284bc..44a251a 100644
--- a/packages/shade-streams/package.json
+++ b/packages/shade-streams/package.json
@@ -1,6 +1,6 @@
 {
   "name": "@shade/streams",
-  "version": "4.7.0",
+  "version": "4.8.0",
   "type": "module",
   "main": "src/index.ts",
   "types": "src/index.ts",
diff --git a/packages/shade-transfer/package.json b/packages/shade-transfer/package.json
index 85f1940..26ea932 100644
--- a/packages/shade-transfer/package.json
+++ b/packages/shade-transfer/package.json
@@ -1,6 +1,6 @@
 {
   "name": "@shade/transfer",
-  "version": "4.7.0",
+  "version": "4.8.0",
   "type": "module",
   "main": "src/index.ts",
   "types": "src/index.ts",
diff --git a/packages/shade-transport-bridge/package.json b/packages/shade-transport-bridge/package.json
index bc74d90..3be7796 100644
--- a/packages/shade-transport-bridge/package.json
+++ b/packages/shade-transport-bridge/package.json
@@ -1,6 +1,6 @@
 {
   "name": "@shade/transport-bridge",
-  "version": "4.7.0",
+  "version": "4.8.0",
   "type": "module",
   "main": "src/index.ts",
   "types": "src/index.ts",
diff --git a/packages/shade-transport-bridge/tests/bridge.test.ts b/packages/shade-transport-bridge/tests/bridge.test.ts
index b7419e9..8744a55 100644
--- a/packages/shade-transport-bridge/tests/bridge.test.ts
+++ b/packages/shade-transport-bridge/tests/bridge.test.ts
@@ -867,3 +867,87 @@ describe('PresenceBridge — subscribe to remote presence changes', () => {
     }
   });
 });
+
+// ─── V4.8 — sender-fingerprint propagation on bridge push ──────────
+
+describe('Sender attribution — bridge push surfaces IncomingMessage.from', () => {
+  test('SSE push carries from = 8-byte hex of SHA-256(senderSigningKey)', async () => {
+    const h = await bootstrap();
+    try {
+      const received: IncomingMessage[] = [];
+      const bridge = new SseBridge({
+        baseUrl: h.baseUrl,
+        auth: bobAuth(h),
+        initialBackoffMs: 50,
+        maxBackoffMs: 200,
+        disableAutoReconnect: true,
+      });
+      await bridge.connect({ onMessage: (m) => received.push(m) });
+      try {
+        await putBlob(h, rand(48));
+        await waitFor(() => received.length === 1, 5_000);
+        const fp = received[0]!.from;
+        expect(fp).toMatch(/^[0-9a-f]{16}$/);
+        const digest = await globalThis.crypto.subtle.digest(
+          'SHA-256',
+          h.alice.signingPublicKey as unknown as ArrayBuffer,
+        );
+        const expected = Array.from(new Uint8Array(digest).slice(0, 8), (b) =>
+          b.toString(16).padStart(2, '0'),
+        ).join('');
+        expect(fp).toBe(expected);
+      } finally {
+        await bridge.disconnect();
+      }
+    } finally {
+      h.server.stop(true);
+    }
+  });
+
+  test('WS push carries from likewise', async () => {
+    const h = await bootstrap();
+    try {
+      const received: IncomingMessage[] = [];
+      const bridge = new WsBridge({
+        baseUrl: h.baseUrl,
+        auth: bobAuth(h),
+        connectTimeoutMs: 2_000,
+        disableAutoReconnect: true,
+      });
+      await bridge.connect({ onMessage: (m) => received.push(m) });
+      try {
+        await putBlob(h, rand(48));
+        await waitFor(() => received.length === 1, 5_000);
+        expect(received[0]!.from).toMatch(/^[0-9a-f]{16}$/);
+      } finally {
+        await bridge.disconnect();
+      }
+    } finally {
+      h.server.stop(true);
+    }
+  });
+
+  test('long-poll push carries from likewise', async () => {
+    const h = await bootstrap();
+    try {
+      const received: IncomingMessage[] = [];
+      const bridge = new LongPollBridge({
+        baseUrl: h.baseUrl,
+        auth: bobAuth(h),
+        pollTimeoutMs: 500,
+        requestTimeoutMs: 1_500,
+        errorBackoffMs: 50,
+      });
+      await bridge.connect({ onMessage: (m) => received.push(m) });
+      try {
+        await putBlob(h, rand(48));
+        await waitFor(() => received.length === 1, 5_000);
+        expect(received[0]!.from).toMatch(/^[0-9a-f]{16}$/);
+      } finally {
+        await bridge.disconnect();
+      }
+    } finally {
+      h.server.stop(true);
+    }
+  });
+});
diff --git a/packages/shade-transport-webrtc/package.json b/packages/shade-transport-webrtc/package.json
index a2b8861..98e7df4 100644
--- a/packages/shade-transport-webrtc/package.json
+++ b/packages/shade-transport-webrtc/package.json
@@ -1,6 +1,6 @@
 {
   "name": "@shade/transport-webrtc",
-  "version": "4.7.0",
+  "version": "4.8.0",
   "type": "module",
   "main": "src/index.ts",
   "types": "src/index.ts",
diff --git a/packages/shade-transport/package.json b/packages/shade-transport/package.json
index 1303eba..f36961c 100644
--- a/packages/shade-transport/package.json
+++ b/packages/shade-transport/package.json
@@ -1,6 +1,6 @@
 {
   "name": "@shade/transport",
-  "version": "4.7.0",
+  "version": "4.8.0",
   "type": "module",
   "main": "src/index.ts",
   "types": "src/index.ts",
diff --git a/packages/shade-widgets/package.json b/packages/shade-widgets/package.json
index 3760b34..b01f67f 100644
--- a/packages/shade-widgets/package.json
+++ b/packages/shade-widgets/package.json
@@ -1,6 +1,6 @@
 {
   "name": "@shade/widgets",
-  "version": "4.7.0",
+  "version": "4.8.0",
   "type": "module",
   "main": "src/index.ts",
   "types": "src/index.ts",