diff --git a/packages/server/scripts/measure-git-observation.ts b/packages/server/scripts/measure-git-observation.ts
index c501a333b..ecd6d07f2 100644
--- a/packages/server/scripts/measure-git-observation.ts
+++ b/packages/server/scripts/measure-git-observation.ts
@@ -17,6 +17,7 @@ import {
 } from "../src/utils/run-git-command.js";
 import { CheckoutDiffManager } from "../src/server/checkout-diff-manager.js";
 import {
+  subscribeToWorkspaceFileChanges,
   WorkspaceGitServiceImpl,
   type WorkspaceGitRuntimeSnapshot,
 } from "../src/server/workspace-git-service.js";
@@ -94,7 +95,7 @@ function createTrackedSubscriber(failWorktreeRoot: string | null) {
     if (failWorktreeRoot && path.resolve(args[0]) === failWorktreeRoot) {
       throw new Error("measurement watcher setup failure");
     }
-    const subscription = await parcelWatcher.subscribe(...args);
+    const subscription = await subscribeToWorkspaceFileChanges(...args);
     subscriptions.add(subscription);
     return {
       unsubscribe: async () => {
diff --git a/packages/server/src/server/workspace-git-service.observation.integration.test.ts b/packages/server/src/server/workspace-git-service.observation.integration.test.ts
index 8decb8ca8..70e60fe16 100644
--- a/packages/server/src/server/workspace-git-service.observation.integration.test.ts
+++ b/packages/server/src/server/workspace-git-service.observation.integration.test.ts
@@ -6,7 +6,10 @@ import type pino from "pino";
 import { afterEach, expect, test, vi } from "vitest";
 import type { CheckoutSnapshotFacts, CheckoutStatusGit } from "../utils/checkout-git.js";
 import { CheckoutDiffManager } from "./checkout-diff-manager.js";
-import { WorkspaceGitServiceImpl } from "./workspace-git-service.js";
+import {
+  subscribeToWorkspaceFileChanges,
+  WorkspaceGitServiceImpl,
+} from "./workspace-git-service.js";
 
 function createLogger(): pino.Logger {
   const logger = {
@@ -83,7 +86,7 @@ test("native recursive observation updates tracked state and prunes ignored stor
     events: parcelWatcher.Event[];
   }> = [];
   const subscribe: typeof parcelWatcher.subscribe = async (directory, callback, options) => {
-    const subscription = await parcelWatcher.subscribe(
+    const subscription = await subscribeToWorkspaceFileChanges(
       directory,
       (error, events) => {
         deliveredEvents.push({ directory, events });
@@ -194,9 +197,19 @@ test("native recursive observation updates tracked state and prunes ignored stor
     { timeout: 5_000 },
   );
 
-  // Parcel may deliver a startup batch before subscribe resolves. Let its
-  // already-scheduled consumer debounce finish inside the bootstrap phase.
-  await new Promise((resolve) => setTimeout(resolve, 250));
+  writeFileSync(trackedPath, "base\n");
+  await vi.waitFor(
+    () => {
+      const events = deliveredEvents.flatMap((batch) => batch.events);
+      expect(events.map((event) => event.path)).toContain(trackedPath);
+      expect(getCheckoutWorktreeState).toHaveBeenCalled();
+      expect(service.getMetrics()).toMatchObject({
+        workspaceRefreshInFlightCount: 0,
+        workspaceRefreshQueuedCount: 0,
+      });
+    },
+    { timeout: 5_000 },
+  );
 
   getCheckoutSnapshotFacts.mockClear();
   getCheckoutStatus.mockClear();
@@ -206,7 +219,6 @@ test("native recursive observation updates tracked state and prunes ignored stor
   runGitCommand.mockClear();
   deliveredEvents.length = 0;
 
-  await new Promise((resolve) => setTimeout(resolve, 250));
   expect(runGitCommand).not.toHaveBeenCalled();
   expect(getCheckoutWorktreeState).not.toHaveBeenCalled();
   expect(getCheckoutDiff, JSON.stringify(deliveredEvents)).not.toHaveBeenCalled();
diff --git a/packages/server/src/server/workspace-git-service.primitive.test.ts b/packages/server/src/server/workspace-git-service.primitive.test.ts
index 77380d72b..f0669c2f1 100644
--- a/packages/server/src/server/workspace-git-service.primitive.test.ts
+++ b/packages/server/src/server/workspace-git-service.primitive.test.ts
@@ -19,6 +19,7 @@ import {
 } from "../utils/checkout-git.js";
 import { runGitCommand as runGitCommandReal } from "../utils/run-git-command.js";
 import {
+  getWorkspaceFileWatcherBackend,
   getWorkspaceGitSelfHealPhaseMs,
   WorkspaceGitServiceImpl,
   type WorkspaceGitRuntimeSnapshot,
@@ -891,6 +892,20 @@ describe("WorkspaceGitServiceImpl primitive refresh entrypoint", () => {
     expect(getWorkspaceGitSelfHealPhaseMs("/tmp/staggered-repo")).toBe(9_817);
   });
 
+  test.each([
+    ["darwin", "fs-events"],
+    ["linux", "inotify"],
+    ["win32", "windows"],
+  ] as const)("uses the native %s file watcher backend", (platform, backend) => {
+    expect(getWorkspaceFileWatcherBackend(platform)).toBe(backend);
+  });
+
+  test("rejects unsupported watcher platforms instead of using backend auto-detection", () => {
+    expect(() => getWorkspaceFileWatcherBackend("freebsd")).toThrow(
+      "No native workspace file watcher configured for freebsd",
+    );
+  });
+
   test("self-heal staggers workspaces and settles into a 120 second cadence", async () => {
     vi.setSystemTime(0);
     const otherRepoCwd = resolvePath("/tmp/staggered-repo");
diff --git a/packages/server/src/server/workspace-git-service.ts b/packages/server/src/server/workspace-git-service.ts
index f74c9670c..86ea5902b 100644
--- a/packages/server/src/server/workspace-git-service.ts
+++ b/packages/server/src/server/workspace-git-service.ts
@@ -306,6 +306,32 @@ interface WorkspaceGitServiceOptions {
   deps?: Partial<WorkspaceGitServiceDependencies>;
 }
 
+export function getWorkspaceFileWatcherBackend(
+  platform: NodeJS.Platform,
+): parcelWatcher.BackendType {
+  switch (platform) {
+    case "darwin":
+      return "fs-events";
+    case "linux":
+      return "inotify";
+    case "win32":
+      return "windows";
+    default:
+      throw new Error(`No native workspace file watcher configured for ${platform}`);
+  }
+}
+
+export function subscribeToWorkspaceFileChanges(
+  directory: string,
+  callback: parcelWatcher.SubscribeCallback,
+  options?: parcelWatcher.Options,
+): Promise<parcelWatcher.AsyncSubscription> {
+  return parcelWatcher.subscribe(directory, callback, {
+    ...options,
+    backend: getWorkspaceFileWatcherBackend(process.platform),
+  });
+}
+
 interface WorkspaceGitTarget {
   cwd: string;
   listeners: Set<WorkspaceGitListener>;
@@ -375,7 +401,7 @@ interface WorkspaceForgePrStatusPollTarget {
 
 function buildDefaultWorkspaceGitServiceDeps(): WorkspaceGitServiceDependencies {
   return {
-    subscribe: parcelWatcher.subscribe,
+    subscribe: subscribeToWorkspaceFileChanges,
     getCheckoutSnapshotFacts,
     getCheckoutStatus,
     getCheckoutShortstat,