diff --git a/apps/code/src/main/index.ts b/apps/code/src/main/index.ts
index bcacac6ab..4f17c0404 100644
--- a/apps/code/src/main/index.ts
+++ b/apps/code/src/main/index.ts
@@ -55,6 +55,10 @@ import {
   focusWorktreePaths,
 } from "./services/focus/desktop-adapters";
 import type { WorkspaceServerService } from "./services/workspace-server/service";
+import {
+  collectMemorySnapshot,
+  flattenMemorySnapshot,
+} from "./utils/crash-diagnostics";
 import { ensureClaudeConfigDir } from "./utils/env";
 import {
   getChromiumLogFilePath,
@@ -129,6 +133,14 @@ function isCrashLoop(): boolean {
   return recentCrashTimestamps.length >= CRASH_LOOP_THRESHOLD;
 }
 
+function crashDiagnostics() {
+  return {
+    appUptimeSeconds: Math.round(process.uptime()),
+    chromiumLogTail: readChromiumLogTail(),
+    ...flattenMemorySnapshot(collectMemorySnapshot(() => app.getAppMetrics())),
+  };
+}
+
 app.on("render-process-gone", (_event, webContents, details) => {
   const props = {
     source: "main",
@@ -138,14 +150,15 @@ app.on("render-process-gone", (_event, webContents, details) => {
     url: webContents.getURL(),
     title: webContents.getTitle(),
     webContentsId: String(webContents.id),
+    ...crashDiagnostics(),
   };
-  log.error("Renderer process gone", {
-    ...props,
-    chromiumLogTail: readChromiumLogTail(),
-  });
+  log.error("Renderer process gone", props);
   posthogNodeAnalytics.captureException(
     new Error(`Renderer process gone: ${details.reason}`),
-    props,
+    {
+      ...props,
+      $exception_fingerprint: ["render-process-gone", details.reason],
+    },
   );
   posthogNodeAnalytics.flush().catch(() => {});
 
@@ -185,14 +198,19 @@ app.on("child-process-gone", (_event, details) => {
     exitCode: String(details.exitCode),
     serviceName: details.serviceName ?? "",
     name: details.name ?? "",
+    ...crashDiagnostics(),
   };
-  log.error("Child process gone", {
-    ...props,
-    chromiumLogTail: readChromiumLogTail(),
-  });
+  log.error("Child process gone", props);
   posthogNodeAnalytics.captureException(
     new Error(`Child process gone (${details.type}): ${details.reason}`),
-    props,
+    {
+      ...props,
+      $exception_fingerprint: [
+        "child-process-gone",
+        details.type,
+        details.reason,
+      ],
+    },
   );
   posthogNodeAnalytics.flush().catch(() => {});
 });
diff --git a/apps/code/src/main/platform-adapters/posthog-analytics.test.ts b/apps/code/src/main/platform-adapters/posthog-analytics.test.ts
index 1131c97e1..d0e605987 100644
--- a/apps/code/src/main/platform-adapters/posthog-analytics.test.ts
+++ b/apps/code/src/main/platform-adapters/posthog-analytics.test.ts
@@ -93,4 +93,22 @@ describe("posthog-analytics", () => {
       }),
     );
   });
+
+  it("stamps the main-owned session id and ignores a caller override", () => {
+    posthogNodeAnalytics.captureException(new Error("boom"), {
+      $session_id: "spoofed",
+    });
+
+    const [, , props] = mockCaptureException.mock.calls.at(-1) ?? [];
+    expect(props.$session_id).toBe(posthogNodeAnalytics.getOrCreateSessionId());
+  });
+
+  it("mints a stable valid uuidv7 session id", () => {
+    const first = posthogNodeAnalytics.getOrCreateSessionId();
+
+    expect(posthogNodeAnalytics.getOrCreateSessionId()).toBe(first);
+    expect(first).toMatch(
+      /^[0-9a-f]{8}-[0-9a-f]{4}-7[0-9a-f]{3}-[89ab][0-9a-f]{3}-[0-9a-f]{12}$/,
+    );
+  });
 });
diff --git a/apps/code/src/main/platform-adapters/posthog-analytics.ts b/apps/code/src/main/platform-adapters/posthog-analytics.ts
index 8a3183b1c..27ef9c0e0 100644
--- a/apps/code/src/main/platform-adapters/posthog-analytics.ts
+++ b/apps/code/src/main/platform-adapters/posthog-analytics.ts
@@ -4,10 +4,12 @@ import type {
 } from "@posthog/platform/analytics";
 import { PostHog } from "posthog-node";
 import { getAppVersion } from "../utils/env";
+import { uuidv7 } from "../utils/uuidv7";
 
 export class PosthogNodeAnalytics implements IAnalytics {
   private client: PostHog | null = null;
   private currentUserId: string | null = null;
+  private sessionId: string | null = null;
 
   initialize(): void {
     if (this.client) {
@@ -25,6 +27,8 @@ export class PosthogNodeAnalytics implements IAnalytics {
       host: apiHost || "https://internal-c.posthog.com",
       enableExceptionAutocapture: true,
     });
+
+    this.getOrCreateSessionId();
   }
 
   setCurrentUserId(userId: string | null): void {
@@ -35,6 +39,13 @@ export class PosthogNodeAnalytics implements IAnalytics {
     return this.currentUserId;
   }
 
+  getOrCreateSessionId(): string {
+    if (!this.sessionId) {
+      this.sessionId = uuidv7();
+    }
+    return this.sessionId;
+  }
+
   track(eventName: string, properties?: AnalyticsProperties): void {
     if (!this.client) {
       return;
@@ -83,6 +94,7 @@ export class PosthogNodeAnalytics implements IAnalytics {
     this.client.captureException(error, distinctId, {
       team: "posthog-code",
       ...additionalProperties,
+      ...(this.sessionId ? { $session_id: this.sessionId } : {}),
       app_version: getAppVersion(),
     });
   }
diff --git a/apps/code/src/main/utils/crash-diagnostics.test.ts b/apps/code/src/main/utils/crash-diagnostics.test.ts
new file mode 100644
index 000000000..7a896108a
--- /dev/null
+++ b/apps/code/src/main/utils/crash-diagnostics.test.ts
@@ -0,0 +1,73 @@
+import { describe, expect, it } from "vitest";
+import {
+  collectMemorySnapshot,
+  flattenMemorySnapshot,
+} from "./crash-diagnostics";
+
+function metric(
+  type: string,
+  workingSetSize: number,
+  peakWorkingSetSize: number,
+): Electron.ProcessMetric {
+  return {
+    type,
+    memory: { workingSetSize, peakWorkingSetSize, privateBytes: 0 },
+  } as unknown as Electron.ProcessMetric;
+}
+
+describe("collectMemorySnapshot", () => {
+  it("sums working set, tracks peak, and groups by process type", () => {
+    const snapshot = collectMemorySnapshot(() => [
+      metric("Browser", 100, 150),
+      metric("Tab", 200, 500),
+      metric("Tab", 50, 60),
+      metric("GPU", 80, 90),
+    ]);
+
+    expect(snapshot).toEqual({
+      totalWorkingSetKb: 430,
+      peakWorkingSetKb: 500,
+      processCount: 4,
+      byType: { Browser: 100, Tab: 250, GPU: 80 },
+    });
+  });
+
+  it("returns a zeroed snapshot for no processes", () => {
+    expect(collectMemorySnapshot(() => [])).toEqual({
+      totalWorkingSetKb: 0,
+      peakWorkingSetKb: 0,
+      processCount: 0,
+      byType: {},
+    });
+  });
+
+  it("returns undefined instead of throwing (crash handler must not fail)", () => {
+    expect(
+      collectMemorySnapshot(() => {
+        throw new Error("getAppMetrics unavailable");
+      }),
+    ).toBeUndefined();
+  });
+});
+
+describe("flattenMemorySnapshot", () => {
+  it("flattens scalars and serializes byType for PostHog", () => {
+    expect(
+      flattenMemorySnapshot({
+        totalWorkingSetKb: 430,
+        peakWorkingSetKb: 500,
+        processCount: 4,
+        byType: { Browser: 100, Tab: 250, GPU: 80 },
+      }),
+    ).toEqual({
+      memoryTotalWorkingSetKb: 430,
+      memoryPeakWorkingSetKb: 500,
+      memoryProcessCount: 4,
+      memoryByType: '{"Browser":100,"Tab":250,"GPU":80}',
+    });
+  });
+
+  it("returns an empty object when no snapshot was collected", () => {
+    expect(flattenMemorySnapshot(undefined)).toEqual({});
+  });
+});
diff --git a/apps/code/src/main/utils/crash-diagnostics.ts b/apps/code/src/main/utils/crash-diagnostics.ts
new file mode 100644
index 000000000..7abf6c649
--- /dev/null
+++ b/apps/code/src/main/utils/crash-diagnostics.ts
@@ -0,0 +1,48 @@
+export interface MemorySnapshot {
+  totalWorkingSetKb: number;
+  peakWorkingSetKb: number;
+  processCount: number;
+  byType: Record<string, number>;
+}
+
+export function collectMemorySnapshot(
+  getMetrics: () => Electron.ProcessMetric[],
+): MemorySnapshot | undefined {
+  try {
+    const metrics = getMetrics();
+    let totalWorkingSetKb = 0;
+    let peakWorkingSetKb = 0;
+    const byType: Record<string, number> = {};
+    for (const metric of metrics) {
+      const workingSet = metric.memory.workingSetSize;
+      totalWorkingSetKb += workingSet;
+      peakWorkingSetKb = Math.max(
+        peakWorkingSetKb,
+        metric.memory.peakWorkingSetSize,
+      );
+      byType[metric.type] = (byType[metric.type] ?? 0) + workingSet;
+    }
+    return {
+      totalWorkingSetKb,
+      peakWorkingSetKb,
+      processCount: metrics.length,
+      byType,
+    };
+  } catch {
+    return undefined;
+  }
+}
+
+export function flattenMemorySnapshot(
+  memory: MemorySnapshot | undefined,
+): Record<string, number | string> {
+  if (!memory) {
+    return {};
+  }
+  return {
+    memoryTotalWorkingSetKb: memory.totalWorkingSetKb,
+    memoryPeakWorkingSetKb: memory.peakWorkingSetKb,
+    memoryProcessCount: memory.processCount,
+    memoryByType: JSON.stringify(memory.byType),
+  };
+}
diff --git a/apps/code/src/main/utils/uuidv7.test.ts b/apps/code/src/main/utils/uuidv7.test.ts
new file mode 100644
index 000000000..a2516d686
--- /dev/null
+++ b/apps/code/src/main/utils/uuidv7.test.ts
@@ -0,0 +1,39 @@
+import { describe, expect, it, vi } from "vitest";
+import { uuidv7 } from "./uuidv7";
+
+const UUID_V7 =
+  /^[0-9a-f]{8}-[0-9a-f]{4}-7[0-9a-f]{3}-[89ab][0-9a-f]{3}-[0-9a-f]{12}$/;
+
+describe("uuidv7", () => {
+  it("produces a valid v7 string (version nibble 7, variant 10)", () => {
+    for (let i = 0; i < 100; i++) {
+      expect(uuidv7()).toMatch(UUID_V7);
+    }
+  });
+
+  it("encodes the current time so ids sort in creation order", () => {
+    const before = Date.now();
+    const id = uuidv7();
+    const after = Date.now();
+
+    const stampMs = Number.parseInt(id.slice(0, 8) + id.slice(9, 13), 16);
+    expect(stampMs).toBeGreaterThanOrEqual(before);
+    expect(stampMs).toBeLessThanOrEqual(after);
+  });
+
+  it("is unique across rapid calls", () => {
+    const ids = new Set(Array.from({ length: 1000 }, () => uuidv7()));
+    expect(ids.size).toBe(1000);
+  });
+
+  it("writes the 48-bit millisecond timestamp big-endian into the first 6 bytes", () => {
+    vi.spyOn(Date, "now").mockReturnValue(0x0123456789ab);
+    try {
+      const id = uuidv7();
+      expect(id.slice(0, 8)).toBe("01234567");
+      expect(id.slice(9, 13)).toBe("89ab");
+    } finally {
+      vi.restoreAllMocks();
+    }
+  });
+});
diff --git a/apps/code/src/main/utils/uuidv7.ts b/apps/code/src/main/utils/uuidv7.ts
new file mode 100644
index 000000000..de256136f
--- /dev/null
+++ b/apps/code/src/main/utils/uuidv7.ts
@@ -0,0 +1,19 @@
+import { randomBytes } from "node:crypto";
+
+export function uuidv7(): string {
+  const bytes = randomBytes(16);
+  const timestamp = Date.now();
+
+  bytes[0] = Math.floor(timestamp / 2 ** 40) & 0xff;
+  bytes[1] = Math.floor(timestamp / 2 ** 32) & 0xff;
+  bytes[2] = Math.floor(timestamp / 2 ** 24) & 0xff;
+  bytes[3] = Math.floor(timestamp / 2 ** 16) & 0xff;
+  bytes[4] = Math.floor(timestamp / 2 ** 8) & 0xff;
+  bytes[5] = timestamp & 0xff;
+
+  bytes[6] = (bytes[6] & 0x0f) | 0x70; // version 7
+  bytes[8] = (bytes[8] & 0x3f) | 0x80; // variant 10
+
+  const hex = bytes.toString("hex");
+  return `${hex.slice(0, 8)}-${hex.slice(8, 12)}-${hex.slice(12, 16)}-${hex.slice(16, 20)}-${hex.slice(20)}`;
+}
diff --git a/apps/code/src/main/window.ts b/apps/code/src/main/window.ts
index 73d7d3e05..e9df218cc 100644
--- a/apps/code/src/main/window.ts
+++ b/apps/code/src/main/window.ts
@@ -14,6 +14,7 @@ import { container } from "./di/container";
 import { buildApplicationMenu } from "./menu";
 import type { ElectronMainWindow } from "./platform-adapters/electron-main-window";
 import { trpcRouter } from "./trpc/router";
+import { collectMemorySnapshot } from "./utils/crash-diagnostics";
 import { isDevBuild } from "./utils/env";
 import { logger, readChromiumLogTail } from "./utils/logger";
 import { type WindowStateSchema, windowStateStore } from "./utils/store";
@@ -106,6 +107,7 @@ function setupCrashLogging(window: BrowserWindow): void {
       reason: details.reason,
       exitCode: details.exitCode,
       url: window.webContents.getURL(),
+      memory: collectMemorySnapshot(() => app.getAppMetrics()),
       chromiumLogTail: readChromiumLogTail(),
     });
   });
@@ -113,6 +115,7 @@ function setupCrashLogging(window: BrowserWindow): void {
   window.on("unresponsive", () => {
     log.warn("Window unresponsive", {
       url: window.webContents.getURL(),
+      memory: collectMemorySnapshot(() => app.getAppMetrics()),
       chromiumLogTail: readChromiumLogTail(),
     });
   });
diff --git a/apps/code/src/renderer/contributions/app-boot.contributions.ts b/apps/code/src/renderer/contributions/app-boot.contributions.ts
index 194042acd..040573f6e 100644
--- a/apps/code/src/renderer/contributions/app-boot.contributions.ts
+++ b/apps/code/src/renderer/contributions/app-boot.contributions.ts
@@ -12,13 +12,21 @@ const log = logger.scope("app-boot");
 @injectable()
 export class AnalyticsBootContribution implements Contribution {
   start(): void {
-    initializePostHog();
-    trpcClient.os.getAppVersion
-      .query()
-      .then(registerAppVersion)
-      .catch((error) => {
-        log.warn("Failed to register app version super property", { error });
-      });
+    void (async () => {
+      let sessionId: string | undefined;
+      try {
+        ({ sessionId } = await trpcClient.analytics.getSessionId.query());
+      } catch (error) {
+        log.warn("Failed to fetch session id from main", { error });
+      }
+      initializePostHog(sessionId);
+      trpcClient.os.getAppVersion
+        .query()
+        .then(registerAppVersion)
+        .catch((error) => {
+          log.warn("Failed to register app version super property", { error });
+        });
+    })();
   }
 }
 
diff --git a/packages/host-router/src/routers/analytics.router.ts b/packages/host-router/src/routers/analytics.router.ts
index 3e8425bfe..1ced4d3b6 100644
--- a/packages/host-router/src/routers/analytics.router.ts
+++ b/packages/host-router/src/routers/analytics.router.ts
@@ -24,6 +24,14 @@ export const analyticsRouter = router({
       }
     }),
 
+  getSessionId: publicProcedure
+    .output(z.object({ sessionId: z.string() }))
+    .query(({ ctx }) => ({
+      sessionId: ctx.container
+        .get<IAnalytics>(ANALYTICS_SERVICE)
+        .getOrCreateSessionId(),
+    })),
+
   resetUser: publicProcedure.mutation(({ ctx }) => {
     ctx.container.get<IAnalytics>(ANALYTICS_SERVICE).resetUser();
   }),
diff --git a/packages/platform/src/analytics.ts b/packages/platform/src/analytics.ts
index 2c5e9d7ec..425dbc6a4 100644
--- a/packages/platform/src/analytics.ts
+++ b/packages/platform/src/analytics.ts
@@ -6,6 +6,8 @@ export interface IAnalytics {
   identify(userId: string, properties?: AnalyticsProperties): void;
   setCurrentUserId(userId: string | null): void;
   getCurrentUserId(): string | null;
+  /** Host-owned analytics session id, minted lazily on first request. */
+  getOrCreateSessionId(): string;
   resetUser(): void;
   captureException(
     error: unknown,
diff --git a/packages/ui/src/shell/posthogAnalyticsImpl.test.ts b/packages/ui/src/shell/posthogAnalyticsImpl.test.ts
index 41429827f..37e1cc8c6 100644
--- a/packages/ui/src/shell/posthogAnalyticsImpl.test.ts
+++ b/packages/ui/src/shell/posthogAnalyticsImpl.test.ts
@@ -148,4 +148,29 @@ describe("initializePostHog", () => {
     expect(mockPosthog.init).not.toHaveBeenCalled();
     expect(mockPosthog.onFeatureFlags).not.toHaveBeenCalled();
   });
+
+  it("bootstraps posthog with the main-owned session id", async () => {
+    const { initializePostHog } = await loadAnalytics();
+
+    initializePostHog("0190abcd-1234-7890-8abc-def012345678");
+
+    expect(mockPosthog.init).toHaveBeenCalledWith(
+      "test-key",
+      expect.objectContaining({
+        bootstrap: { sessionID: "0190abcd-1234-7890-8abc-def012345678" },
+        session_idle_timeout_seconds: 36_000,
+      }),
+    );
+  });
+
+  it("omits bootstrap when no session id is provided", async () => {
+    const { initializePostHog } = await loadAnalytics();
+
+    initializePostHog();
+
+    expect(mockPosthog.init).toHaveBeenCalledWith(
+      "test-key",
+      expect.not.objectContaining({ bootstrap: expect.anything() }),
+    );
+  });
 });
diff --git a/packages/ui/src/shell/posthogAnalyticsImpl.ts b/packages/ui/src/shell/posthogAnalyticsImpl.ts
index a60bea641..e4ddbada6 100644
--- a/packages/ui/src/shell/posthogAnalyticsImpl.ts
+++ b/packages/ui/src/shell/posthogAnalyticsImpl.ts
@@ -41,7 +41,9 @@ type PendingFlagListener = {
 // Subscribers added before initializePostHog runs.
 const pendingFlagListeners = new Set<PendingFlagListener>();
 
-export function initializePostHog() {
+const SESSION_IDLE_TIMEOUT_SECONDS = 36_000;
+
+export function initializePostHog(sessionId?: string) {
   const apiKey = import.meta.env.VITE_POSTHOG_API_KEY;
   const apiHost =
     import.meta.env.VITE_POSTHOG_API_HOST || "https://internal-c.posthog.com";
@@ -56,6 +58,8 @@ export function initializePostHog() {
     api_host: apiHost,
     ui_host: uiHost,
     disable_session_recording: false,
+    session_idle_timeout_seconds: SESSION_IDLE_TIMEOUT_SECONDS,
+    ...(sessionId ? { bootstrap: { sessionID: sessionId } } : {}),
     capture_exceptions: import.meta.env.DEV
       ? false
       : {