[rush-daemon][WS2] Add daemon host bootstrap (#5928)

* [rush-daemon] Add daemon host bootstrap

Co-authored-by: Copilot App <223556219+Copilot@users.noreply.github.com>

* [rush-daemon] Refresh injected dependency metadata

Co-authored-by: Copilot App <223556219+Copilot@users.noreply.github.com>

* [rush-daemon-protocol] Preserve pong compatibility

Co-authored-by: Copilot App <223556219+Copilot@users.noreply.github.com>

* [rush-daemon] Move rushd entrypoint into daemon package

Co-authored-by: Copilot App <223556219+Copilot@users.noreply.github.com>

---------

Co-authored-by: mojaza <mojazayeri@users.noreply.github.com>
Co-authored-by: Copilot App <223556219+Copilot@users.noreply.github.com>

Author: 3 people

common/changes/@rushstack/rush-daemon-protocol/mojazayeri-rush-daemon-host-bootstrap_2026-08-17-23-30.json

@@ -0,0 +1,11 @@
+{
+  "changes": [
+    {
+      "packageName": "@rushstack/rush-daemon-protocol",
+      "comment": "Include daemon and protocol version metadata in pong control messages.",
+      "type": "minor"
+    }
+  ],
+  "packageName": "@rushstack/rush-daemon-protocol",
+  "email": "mojazayeri@users.noreply.github.com"
+}

common/changes/@rushstack/rush-daemon/mojazayeri-rush-daemon-host-bootstrap_2026-08-17-23-30.json

@@ -0,0 +1,11 @@
+{
+  "changes": [
+    {
+      "packageName": "@rushstack/rush-daemon",
+      "comment": "Add the rushd executable and workspace-keyed daemon host bootstrap with handshake, liveness, readiness, and clean shutdown lifecycle.",
+      "type": "minor"
+    }
+  ],
+  "packageName": "@rushstack/rush-daemon",
+  "email": "mojazayeri@users.noreply.github.com"
+}

common/config/rush/browser-approved-packages.json

@@ -52,7 +52,7 @@
     },
     {
       "name": "@rushstack/rush-daemon-transport",
-      "allowedCategories": [ "tests" ]
+      "allowedCategories": [ "libraries", "tests" ]
     },
     {
       "name": "@rushstack/rush-serve-dashboard",

common/config/subspaces/default/pnpm-lock.yaml

@@ -292,6 +292,8 @@ export interface IDaemonPongMessage {
     readonly kind: 'pong';
     // (undocumented)
     readonly payload: {
+        readonly daemonVersion?: string;
+        readonly protocolVersion?: IDaemonProtocolVersion;
         readonly uptimeMs: number;
     };
 }

common/reviews/api/rush-daemon-protocol.api.md

@@ -6,6 +6,8 @@
 
 /// <reference types="node" />
 
+import type { IDaemonPaths } from '@rushstack/rush-daemon-transport';
+
 // @public
 export interface IRequestLease {
     // (undocumented)
@@ -23,6 +25,21 @@ export interface IRequestSchedulerAcquireOptions {
     waitTimeoutMs?: number;
 }
 
+// @beta
+export interface IRushDaemonHostOptions {
+    readonly daemonVersion: string;
+    readonly onError?: (error: Error) => void;
+    readonly repoRoot: string;
+    readonly rushVersion: string;
+    readonly startupOptions?: Readonly<Record<string, unknown>>;
+}
+
+// @beta
+export interface IRushDaemonServeOptions extends IRushDaemonHostOptions {
+    readonly onReady?: (host: RushDaemonHost) => void | Promise<void>;
+    readonly shutdownSignal?: AbortSignal;
+}
+
 // @public
 export enum RequestExclusivityClass {
     // (undocumented)
@@ -57,6 +74,17 @@ export enum RequestSchedulerErrorCode {
     WaitTimeout = "WAIT_TIMEOUT"
 }
 
+// @beta
+export class RushDaemonHost {
+    closeAsync(): Promise<void>;
+    // (undocumented)
+    readonly paths: IDaemonPaths;
+    static startAsync(options: IRushDaemonHostOptions): Promise<RushDaemonHost>;
+}
+
+// @beta
+export function serveRushDaemonAsync(options: IRushDaemonServeOptions): Promise<void>;
+
 // (No @packageDocumentation comment for this package)
 
 ```

common/reviews/api/rush-daemon.api.md

@@ -5,7 +5,7 @@ import { isDaemonControlMessageKind } from './DaemonControlMessage';
 import { DaemonProtocolError } from './DaemonProtocolError';
 import { isDaemonVerbosity } from './DaemonVerbosity';
 
-/** Returns `true` when `value` is a plain object. @beta */
+/** Returns `true` when `value` is a non-null object usable as a control record. @beta */
 export function isDaemonControlRecord(value: unknown): value is Record<string, unknown> {
   return typeof value === 'object' && value !== null;
 }
@@ -45,6 +45,12 @@ function validateHelloAck(payload: Record<string, unknown>): void {
   requireStringField(payload, 'sessionId');
 }
 
+function validatePong(payload: Record<string, unknown>): void {
+  if (payload.daemonVersion !== undefined) requireStringField(payload, 'daemonVersion');
+  if (payload.protocolVersion !== undefined) requireVersion(payload);
+  requireNumberField(payload, 'uptimeMs');
+}
+
 function validateSubscribe(payload: Record<string, unknown>): void {
   if (typeof payload.isTTY !== 'boolean') {
     fail('Subscribe message payload.isTTY must be a boolean.');
@@ -73,13 +79,11 @@ const VALIDATORS_BY_KIND: Record<string, ControlValidator> = {
   subscribe: validateSubscribe,
   unsubscribe: noopValidator,
   ping: noopValidator,
-  pong: (payload: Record<string, unknown>) => requireNumberField(payload, 'uptimeMs'),
+  pong: validatePong,
   error: validateError
 };
 
-/**
- * Structurally validates a parsed control message.
- *
+/** Structurally validates a parsed control message.
  * @throws {@link DaemonProtocolError} when the value is not a well-formed control message.
  *
  * @beta

libraries/rush-daemon-protocol/src/ControlMessageValidation.ts

@@ -2,6 +2,7 @@
 // See LICENSE in the project root for license information.
 
 import type { IDaemonClientCaps } from './DaemonClientCaps';
+import type { IDaemonPongMessage } from './DaemonPongMessage';
 import type { DaemonProtocolErrorCode } from './DaemonProtocolError';
 import type { IDaemonProtocolVersion } from './DaemonProtocolVersion';
 
@@ -41,12 +42,6 @@ export interface IDaemonPingMessage {
   readonly payload: DaemonEmptyPayload;
 }
 
-/** The liveness reply. @beta */
-export interface IDaemonPongMessage {
-  readonly kind: 'pong';
-  readonly payload: { readonly uptimeMs: number };
-}
-
 /** A protocol error sent on the wire. @beta */
 export interface IDaemonErrorMessage {
   readonly kind: 'error';
@@ -89,7 +84,7 @@ export const DAEMON_CONTROL_MESSAGE_KINDS: readonly [
   'error'
 ] = ['hello', 'helloAck', 'subscribe', 'unsubscribe', 'ping', 'pong', 'error'];
 
-/** The union of control message `kind` discriminants, derived from the list. @beta */
+/** The union of control message `kind` discriminants, derived from the runtime list. @beta */
 export type DaemonControlMessageKind = (typeof DAEMON_CONTROL_MESSAGE_KINDS)[number];
 
 const CONTROL_KIND_SET: ReadonlySet<string> = new Set<string>(DAEMON_CONTROL_MESSAGE_KINDS);

libraries/rush-daemon-protocol/src/DaemonControlMessage.ts

@@ -0,0 +1,16 @@
+// Copyright (c) Microsoft Corporation. All rights reserved. Licensed under the MIT license.
+// See LICENSE in the project root for license information.
+
+import type { IDaemonProtocolVersion } from './DaemonProtocolVersion';
+
+/** The liveness reply. @beta */
+export interface IDaemonPongMessage {
+  readonly kind: 'pong';
+  readonly payload: {
+    /** The daemon implementation version, when reported by protocol 0.2 or newer. */
+    readonly daemonVersion?: string;
+    /** The daemon wire protocol version, when reported by protocol 0.2 or newer. */
+    readonly protocolVersion?: IDaemonProtocolVersion;
+    readonly uptimeMs: number;
+  };
+}

libraries/rush-daemon-protocol/src/DaemonPongMessage.ts

@@ -34,7 +34,7 @@ export interface IDaemonProtocolVersion {
  */
 export const DAEMON_PROTOCOL_VERSION: IDaemonProtocolVersion = {
   major: 0,
-  minor: 1
+  minor: 2
 };
 
 /**