From ef3cea09213f55d2131a0c56b0817148cdaa3f3d Mon Sep 17 00:00:00 2001
From: John Doe <john.doe@example.com>
Date: Tue, 6 Jan 2026 17:36:07 +0100
Subject: [PATCH 01/20] refactor: impl clock logic

---
 packages/utils/src/lib/clock-epoch.ts         |  82 +++++++++
 .../utils/src/lib/clock-epoch.unit.test.ts    | 161 ++++++++++++++++++
 .../src/lib/vitest-setup-files.ts             |   2 +
 .../test-setup/src/lib/clock.setup-file.ts    |  35 ++++
 .../test-setup/src/lib/process.setup-file.ts  |   8 +
 5 files changed, 288 insertions(+)
 create mode 100644 packages/utils/src/lib/clock-epoch.ts
 create mode 100644 packages/utils/src/lib/clock-epoch.unit.test.ts
 create mode 100644 testing/test-setup/src/lib/clock.setup-file.ts
 create mode 100644 testing/test-setup/src/lib/process.setup-file.ts

diff --git a/packages/utils/src/lib/clock-epoch.ts b/packages/utils/src/lib/clock-epoch.ts
new file mode 100644
index 000000000..9c9ef9818
--- /dev/null
+++ b/packages/utils/src/lib/clock-epoch.ts
@@ -0,0 +1,82 @@
+import process from 'node:process';
+import { threadId } from 'node:worker_threads';
+
+export type Microseconds = number;
+export type Milliseconds = number;
+export type EpochMilliseconds = number;
+
+const hasPerf = (): boolean =>
+  typeof performance !== 'undefined' && typeof performance.now === 'function';
+const hasTimeOrigin = (): boolean =>
+  hasPerf() && typeof (performance as any).timeOrigin === 'number';
+
+const msToUs = (ms: number): Microseconds => Math.round(ms * 1000);
+const usToUs = (us: number): Microseconds => Math.round(us);
+
+/**
+ * Defines clock utilities for time conversions.
+ * Handles time origins in NodeJS and the Browser
+ * Provides process and thread IDs.
+ * @param init
+ */
+export interface EpochClockOptions {
+  pid?: number;
+  tid?: number;
+}
+/**
+ * Creates epoch-based clock utility.
+ * Epoch time has been the time since January 1, 1970 (UNIX epoch).
+ * Date.now gives epoch time in milliseconds.
+ * performance.now() + performance.timeOrigin when available is used for higher precision.
+ */
+export function epochClock(init: EpochClockOptions = {}) {
+  const pid = init.pid ?? process.pid;
+  const tid = init.tid ?? threadId;
+
+  const timeOriginMs = hasTimeOrigin()
+    ? ((performance as any).timeOrigin as number)
+    : undefined;
+
+  const epochNowUs = (): Microseconds => {
+    if (hasTimeOrigin()) {
+      return msToUs((performance as any).timeOrigin + performance.now());
+    }
+    return msToUs(Date.now());
+  };
+
+  const fromEpochUs = (epochUs: Microseconds): Microseconds => usToUs(epochUs);
+
+  const fromEpochMs = (epochMs: EpochMilliseconds): Microseconds =>
+    msToUs(epochMs);
+
+  const fromPerfMs = (perfMs: Milliseconds): Microseconds => {
+    if (timeOriginMs === undefined) {
+      return epochNowUs() - msToUs(performance.now() - perfMs);
+    }
+    return msToUs(timeOriginMs + perfMs);
+  };
+
+  const fromEntryStartTimeMs = (startTimeMs: Milliseconds): Microseconds =>
+    fromPerfMs(startTimeMs);
+  const fromDateNowMs = (dateNowMs: EpochMilliseconds): Microseconds =>
+    fromEpochMs(dateNowMs);
+
+  return {
+    timeOriginMs,
+    pid,
+    tid,
+
+    hasTimeOrigin,
+    epochNowUs,
+    msToUs,
+    usToUs,
+
+    fromEpochMs,
+    fromEpochUs,
+    fromPerfMs,
+    fromEntryStartTimeMs,
+    fromDateNowMs,
+  };
+}
+
+export const defaultClock = epochClock();
diff --git a/packages/utils/src/lib/clock-epoch.unit.test.ts b/packages/utils/src/lib/clock-epoch.unit.test.ts
new file mode 100644
index 000000000..4038b4c45
--- /dev/null
+++ b/packages/utils/src/lib/clock-epoch.unit.test.ts
@@ -0,0 +1,161 @@
+import { afterEach, describe, expect, it, vi } from 'vitest';
+import { defaultClock, epochClock } from './clock-epoch';
+
+describe('epochClock', () => {
+  afterEach(() => {
+    vi.unstubAllGlobals();
+  });
+
+  it('should create epoch clock with defaults', () => {
+    const c = epochClock();
+    expect(c.timeOriginMs).toBe(500_000);
+    expect(c.tid).toBe(1);
+    expect(c.pid).toBe(10001);
+    expect(typeof c.fromEpochMs).toBe('function');
+    expect(typeof c.fromEpochUs).toBe('function');
+    expect(typeof c.fromPerfMs).toBe('function');
+    expect(typeof c.fromEntryStartTimeMs).toBe('function');
+    expect(typeof c.fromDateNowMs).toBe('function');
+  });
+
+  it('should use pid options', () => {
+    expect(epochClock({ pid: 999 })).toStrictEqual(
+      expect.objectContaining({
+        pid: 999,
+        tid: 1,
+      }),
+    );
+  });
+
+  it('should use tid options', () => {
+    expect(epochClock({ tid: 888 })).toStrictEqual(
+      expect.objectContaining({
+        pid: 10001,
+        tid: 888,
+      }),
+    );
+  });
+
+  it('should return undefined if performance.timeOrigin is NOT present', () => {
+    Object.defineProperty(performance, 'timeOrigin', {
+      value: undefined,
+      writable: true,
+      configurable: true,
+    });
+    const c = epochClock();
+    expect(c.hasTimeOrigin()).toBe(false);
+  });
+
+  it('should return timeorigin if performance.timeOrigin is present', () => {
+    const c = epochClock();
+    expect(c.hasTimeOrigin()).toBe(true);
+  });
+
+  it('should support performance clock by default for epochNowUs', () => {
+    const c = epochClock();
+    expect(c.timeOriginMs).toBe(500_000);
+    expect(c.epochNowUs()).toBe(1_000_000_000); // timeOrigin + (Date.now() - timeOrigin) = Date.now()
+  });
+
+  it('should fallback to Date clock by if performance clock is not given in epochNowUs', () => {
+    vi.stubGlobal('performance', {
+      ...performance,
+      timeOrigin: undefined,
+    });
+    const c = epochClock();
+    expect(c.timeOriginMs).toBeUndefined();
+    expect(c.epochNowUs()).toBe(1_000_000_000); // Date.now() * 1000 when performance unavailable
+  });
+
+  it('should fallback to Date clock by if performance clock is NOT given', () => {
+    vi.stubGlobal('performance', {
+      ...performance,
+      timeOrigin: undefined,
+    });
+    const c = epochClock();
+    expect(c.timeOriginMs).toBeUndefined();
+    expect(c.fromPerfMs(100)).toBe(500_100_000); // epochNowUs() - msToUs(performance.now() - perfMs)
+  });
+
+  it.each([
+    [1_000_000_000, 1_000_000_000],
+    [1_001_000_000, 1_001_000_000],
+    [999_000_000, 999_000_000],
+  ])('should convert epoch microseconds to microseconds', (us, result) => {
+    const c = epochClock();
+    expect(c.fromEpochUs(us)).toBe(result);
+  });
+
+  it.each([
+    [1_000_000, 1_000_000_000],
+    [1_001_000.5, 1_001_000_500],
+    [999_000.4, 999_000_400],
+  ])('should convert epoch milliseconds to microseconds', (ms, result) => {
+    const c = epochClock();
+    expect(c.fromEpochMs(ms)).toBe(result);
+  });
+
+  it.each([
+    [0, 500_000_000],
+    [1_000, 501_000_000],
+  ])(
+    'should convert performance milliseconds to microseconds',
+    (perfMs, expected) => {
+      expect(epochClock().fromPerfMs(perfMs)).toBe(expected);
+    },
+  );
+
+  it('should convert entry start time to microseconds', () => {
+    const c = epochClock();
+    expect([
+      c.fromEntryStartTimeMs(0),
+      c.fromEntryStartTimeMs(1_000),
+    ]).toStrictEqual([c.fromPerfMs(0), c.fromPerfMs(1_000)]);
+  });
+
+  it('should convert Date.now() milliseconds to microseconds', () => {
+    const c = epochClock();
+    expect([
+      c.fromDateNowMs(1_000_000),
+      c.fromDateNowMs(2_000_000),
+    ]).toStrictEqual([1_000_000_000, 2_000_000_000]);
+  });
+
+  it('should maintain conversion consistency', () => {
+    const c = epochClock();
+
+    expect({
+      fromEpochUs_2B: c.fromEpochUs(2_000_000_000),
+      fromEpochMs_2M: c.fromEpochMs(2_000_000),
+      fromEpochUs_1B: c.fromEpochUs(1_000_000_000),
+      fromEpochMs_1M: c.fromEpochMs(1_000_000),
+    }).toStrictEqual({
+      fromEpochUs_2B: 2_000_000_000,
+      fromEpochMs_2M: 2_000_000_000,
+      fromEpochUs_1B: 1_000_000_000,
+      fromEpochMs_1M: 1_000_000_000,
+    });
+  });
+
+  it.each([
+    [1_000_000_000.1, 1_000_000_000],
+    [1_000_000_000.4, 1_000_000_000],
+    [1_000_000_000.5, 1_000_000_001],
+    [1_000_000_000.9, 1_000_000_001],
+  ])('should round microseconds correctly', (value, result) => {
+    const c = epochClock();
+    expect(c.fromEpochUs(value)).toBe(result);
+  });
+});
+
+describe('defaultClock', () => {
+  it('should have valid defaultClock export', () => {
+    expect({
+      tid: typeof defaultClock.tid,
+      timeOriginMs: typeof defaultClock.timeOriginMs,
+    }).toStrictEqual({
+      tid: 'number',
+      timeOriginMs: 'number',
+    });
+  });
+});
diff --git a/testing/test-setup-config/src/lib/vitest-setup-files.ts b/testing/test-setup-config/src/lib/vitest-setup-files.ts
index 1d735b2a9..eb9926fd7 100644
--- a/testing/test-setup-config/src/lib/vitest-setup-files.ts
+++ b/testing/test-setup-config/src/lib/vitest-setup-files.ts
@@ -25,6 +25,8 @@ const UNIT_TEST_SETUP_FILES = [
   '../../testing/test-setup/src/lib/logger.mock.ts',
   '../../testing/test-setup/src/lib/git.mock.ts',
   '../../testing/test-setup/src/lib/portal-client.mock.ts',
+  '../../testing/test-setup/src/lib/process.setup-file.ts',
+  '../../testing/test-setup/src/lib/clock.setup-file.ts',
   ...CUSTOM_MATCHERS,
 ] as const;
 
diff --git a/testing/test-setup/src/lib/clock.setup-file.ts b/testing/test-setup/src/lib/clock.setup-file.ts
new file mode 100644
index 000000000..36fd27577
--- /dev/null
+++ b/testing/test-setup/src/lib/clock.setup-file.ts
@@ -0,0 +1,35 @@
+import { type MockInstance, afterEach, beforeEach, vi } from 'vitest';
+
+const MOCK_DATE_NOW_MS = 1_000_000;
+const MOCK_TIME_ORIGIN = 500_000;
+
+const dateNow = MOCK_DATE_NOW_MS;
+const performanceTimeOrigin = MOCK_TIME_ORIGIN;
+
+let dateNowSpy: MockInstance<[], number> | undefined;
+let performanceNowSpy: MockInstance<[], number> | undefined;
+
+beforeEach(() => {
+  dateNowSpy = vi.spyOn(Date, 'now').mockReturnValue(dateNow);
+  performanceNowSpy = vi
+    .spyOn(performance, 'now')
+    .mockReturnValue(dateNow - performanceTimeOrigin);
+
+  vi.stubGlobal('performance', {
+    ...performance,
+    timeOrigin: performanceTimeOrigin,
+  });
+});
+
+afterEach(() => {
+  vi.unstubAllGlobals();
+
+  if (dateNowSpy) {
+    dateNowSpy.mockRestore();
+    dateNowSpy = undefined;
+  }
+  if (performanceNowSpy) {
+    performanceNowSpy.mockRestore();
+    performanceNowSpy = undefined;
+  }
+});
diff --git a/testing/test-setup/src/lib/process.setup-file.ts b/testing/test-setup/src/lib/process.setup-file.ts
new file mode 100644
index 000000000..acc884a40
--- /dev/null
+++ b/testing/test-setup/src/lib/process.setup-file.ts
@@ -0,0 +1,8 @@
+import process from 'node:process';
+import { beforeEach, vi } from 'vitest';
+
+export const MOCK_PID = 10001;
+
+beforeEach(() => {
+  vi.spyOn(process, 'pid', 'get').mockReturnValue(MOCK_PID);
+});

From fc19fcc880d5a86958b580e690f8a8f9d1d4a267 Mon Sep 17 00:00:00 2001
From: John Doe <john.doe@example.com>
Date: Tue, 6 Jan 2026 17:52:58 +0100
Subject: [PATCH 02/20] refactor: fix lint

---
 packages/utils/src/lib/clock-epoch.ts         | 23 +++++++++----------
 .../utils/src/lib/clock-epoch.unit.test.ts    |  9 ++++----
 2 files changed, 15 insertions(+), 17 deletions(-)

diff --git a/packages/utils/src/lib/clock-epoch.ts b/packages/utils/src/lib/clock-epoch.ts
index 9c9ef9818..1a048059a 100644
--- a/packages/utils/src/lib/clock-epoch.ts
+++ b/packages/utils/src/lib/clock-epoch.ts
@@ -8,7 +8,9 @@ export type EpochMilliseconds = number;
 const hasPerf = (): boolean =>
   typeof performance !== 'undefined' && typeof performance.now === 'function';
 const hasTimeOrigin = (): boolean =>
-  hasPerf() && typeof (performance as any).timeOrigin === 'number';
+  hasPerf() &&
+  typeof (performance as { timeOrigin: number | undefined }).timeOrigin ===
+    'number';
 
 const msToUs = (ms: number): Microseconds => Math.round(ms * 1000);
 const usToUs = (us: number): Microseconds => Math.round(us);
@@ -19,10 +21,10 @@ const usToUs = (us: number): Microseconds => Math.round(us);
  * Provides process and thread IDs.
  * @param init
  */
-export interface EpochClockOptions {
+export type EpochClockOptions = {
   pid?: number;
   tid?: number;
-}
+};
 /**
  * Creates epoch-based clock utility.
  * Epoch time has been the time since January 1, 1970 (UNIX epoch).
@@ -34,20 +36,19 @@ export function epochClock(init: EpochClockOptions = {}) {
   const tid = init.tid ?? threadId;
 
   const timeOriginMs = hasTimeOrigin()
-    ? ((performance as any).timeOrigin as number)
+    ? (performance as { timeOrigin: number | undefined }).timeOrigin
     : undefined;
 
   const epochNowUs = (): Microseconds => {
     if (hasTimeOrigin()) {
-      return msToUs((performance as any).timeOrigin + performance.now());
+      return msToUs(performance.timeOrigin + performance.now());
     }
     return msToUs(Date.now());
   };
 
-  const fromEpochUs = (epochUs: Microseconds): Microseconds => usToUs(epochUs);
+  const fromEpochUs = usToUs;
 
-  const fromEpochMs = (epochMs: EpochMilliseconds): Microseconds =>
-    msToUs(epochMs);
+  const fromEpochMs = msToUs;
 
   const fromPerfMs = (perfMs: Milliseconds): Microseconds => {
     if (timeOriginMs === undefined) {
@@ -56,10 +57,8 @@ export function epochClock(init: EpochClockOptions = {}) {
     return msToUs(timeOriginMs + perfMs);
   };
 
-  const fromEntryStartTimeMs = (startTimeMs: Milliseconds): Microseconds =>
-    fromPerfMs(startTimeMs);
-  const fromDateNowMs = (dateNowMs: EpochMilliseconds): Microseconds =>
-    fromEpochMs(dateNowMs);
+  const fromEntryStartTimeMs = fromPerfMs;
+  const fromDateNowMs = fromEpochMs;
 
   return {
     timeOriginMs,
diff --git a/packages/utils/src/lib/clock-epoch.unit.test.ts b/packages/utils/src/lib/clock-epoch.unit.test.ts
index 4038b4c45..7e0609e87 100644
--- a/packages/utils/src/lib/clock-epoch.unit.test.ts
+++ b/packages/utils/src/lib/clock-epoch.unit.test.ts
@@ -1,5 +1,5 @@
 import { afterEach, describe, expect, it, vi } from 'vitest';
-import { defaultClock, epochClock } from './clock-epoch';
+import { defaultClock, epochClock } from './clock-epoch.js';
 
 describe('epochClock', () => {
   afterEach(() => {
@@ -37,10 +37,9 @@ describe('epochClock', () => {
   });
 
   it('should return undefined if performance.timeOrigin is NOT present', () => {
-    Object.defineProperty(performance, 'timeOrigin', {
-      value: undefined,
-      writable: true,
-      configurable: true,
+    vi.stubGlobal('performance', {
+      ...performance,
+      timeOrigin: undefined,
     });
     const c = epochClock();
     expect(c.hasTimeOrigin()).toBe(false);

From 3fe62f1661763890d59889dafd76e0b9cc0ad5e9 Mon Sep 17 00:00:00 2001
From: John Doe <john.doe@example.com>
Date: Tue, 6 Jan 2026 18:06:23 +0100
Subject: [PATCH 03/20] refactor: fix format

---
 packages/utils/src/lib/clock-epoch.unit.test.ts | 10 +++++-----
 1 file changed, 5 insertions(+), 5 deletions(-)

diff --git a/packages/utils/src/lib/clock-epoch.unit.test.ts b/packages/utils/src/lib/clock-epoch.unit.test.ts
index 7e0609e87..ad09418fe 100644
--- a/packages/utils/src/lib/clock-epoch.unit.test.ts
+++ b/packages/utils/src/lib/clock-epoch.unit.test.ts
@@ -10,7 +10,7 @@ describe('epochClock', () => {
     const c = epochClock();
     expect(c.timeOriginMs).toBe(500_000);
     expect(c.tid).toBe(1);
-    expect(c.pid).toBe(10001);
+    expect(c.pid).toBe(10_001);
     expect(typeof c.fromEpochMs).toBe('function');
     expect(typeof c.fromEpochUs).toBe('function');
     expect(typeof c.fromPerfMs).toBe('function');
@@ -30,7 +30,7 @@ describe('epochClock', () => {
   it('should use tid options', () => {
     expect(epochClock({ tid: 888 })).toStrictEqual(
       expect.objectContaining({
-        pid: 10001,
+        pid: 10_001,
         tid: 888,
       }),
     );
@@ -96,7 +96,7 @@ describe('epochClock', () => {
 
   it.each([
     [0, 500_000_000],
-    [1_000, 501_000_000],
+    [1000, 501_000_000],
   ])(
     'should convert performance milliseconds to microseconds',
     (perfMs, expected) => {
@@ -108,8 +108,8 @@ describe('epochClock', () => {
     const c = epochClock();
     expect([
       c.fromEntryStartTimeMs(0),
-      c.fromEntryStartTimeMs(1_000),
-    ]).toStrictEqual([c.fromPerfMs(0), c.fromPerfMs(1_000)]);
+      c.fromEntryStartTimeMs(1000),
+    ]).toStrictEqual([c.fromPerfMs(0), c.fromPerfMs(1000)]);
   });
 
   it('should convert Date.now() milliseconds to microseconds', () => {

From 0e7a06e11ee5ddb7f297fc89122b64472d689be1 Mon Sep 17 00:00:00 2001
From: John Doe <john.doe@example.com>
Date: Tue, 6 Jan 2026 18:10:05 +0100
Subject: [PATCH 04/20] refactor: fix lint

---
 testing/test-setup/src/lib/clock.setup-file.ts   | 2 ++
 testing/test-setup/src/lib/process.setup-file.ts | 2 +-
 2 files changed, 3 insertions(+), 1 deletion(-)

diff --git a/testing/test-setup/src/lib/clock.setup-file.ts b/testing/test-setup/src/lib/clock.setup-file.ts
index 36fd27577..41f86a580 100644
--- a/testing/test-setup/src/lib/clock.setup-file.ts
+++ b/testing/test-setup/src/lib/clock.setup-file.ts
@@ -6,8 +6,10 @@ const MOCK_TIME_ORIGIN = 500_000;
 const dateNow = MOCK_DATE_NOW_MS;
 const performanceTimeOrigin = MOCK_TIME_ORIGIN;
 
+/* eslint-disable functional/no-let */
 let dateNowSpy: MockInstance<[], number> | undefined;
 let performanceNowSpy: MockInstance<[], number> | undefined;
+/* eslint-enable functional/no-let */
 
 beforeEach(() => {
   dateNowSpy = vi.spyOn(Date, 'now').mockReturnValue(dateNow);
diff --git a/testing/test-setup/src/lib/process.setup-file.ts b/testing/test-setup/src/lib/process.setup-file.ts
index acc884a40..bcc4e627b 100644
--- a/testing/test-setup/src/lib/process.setup-file.ts
+++ b/testing/test-setup/src/lib/process.setup-file.ts
@@ -1,7 +1,7 @@
 import process from 'node:process';
 import { beforeEach, vi } from 'vitest';
 
-export const MOCK_PID = 10001;
+export const MOCK_PID = 10_001;
 
 beforeEach(() => {
   vi.spyOn(process, 'pid', 'get').mockReturnValue(MOCK_PID);

From 69bee3173de2eef36704fada4885253a583f70cf Mon Sep 17 00:00:00 2001
From: John Doe <john.doe@example.com>
Date: Wed, 7 Jan 2026 13:40:04 +0100
Subject: [PATCH 05/20] refactor: add mock restore

---
 testing/test-setup/src/lib/process.setup-file.ts | 9 +++++++--
 1 file changed, 7 insertions(+), 2 deletions(-)

diff --git a/testing/test-setup/src/lib/process.setup-file.ts b/testing/test-setup/src/lib/process.setup-file.ts
index bcc4e627b..057662c20 100644
--- a/testing/test-setup/src/lib/process.setup-file.ts
+++ b/testing/test-setup/src/lib/process.setup-file.ts
@@ -1,8 +1,13 @@
 import process from 'node:process';
-import { beforeEach, vi } from 'vitest';
+import { afterEach, beforeEach, vi } from 'vitest';
 
 export const MOCK_PID = 10_001;
 
+let processMock = vi.spyOn(process, 'pid', 'get');
 beforeEach(() => {
-  vi.spyOn(process, 'pid', 'get').mockReturnValue(MOCK_PID);
+  processMock.mockReturnValue(MOCK_PID);
+});
+
+afterEach(() => {
+  processMock.mockRestore();
 });

From db253450c3f04755b3d8ca2aec9bf8efbc7a49df Mon Sep 17 00:00:00 2001
From: John Doe <john.doe@example.com>
Date: Wed, 7 Jan 2026 14:55:54 +0100
Subject: [PATCH 06/20] refactor: add mock clear

---
 testing/test-setup/src/lib/process.setup-file.ts | 4 ++--
 1 file changed, 2 insertions(+), 2 deletions(-)

diff --git a/testing/test-setup/src/lib/process.setup-file.ts b/testing/test-setup/src/lib/process.setup-file.ts
index 057662c20..770e00803 100644
--- a/testing/test-setup/src/lib/process.setup-file.ts
+++ b/testing/test-setup/src/lib/process.setup-file.ts
@@ -3,11 +3,11 @@ import { afterEach, beforeEach, vi } from 'vitest';
 
 export const MOCK_PID = 10_001;
 
-let processMock = vi.spyOn(process, 'pid', 'get');
+const processMock = vi.spyOn(process, 'pid', 'get');
 beforeEach(() => {
   processMock.mockReturnValue(MOCK_PID);
 });
 
 afterEach(() => {
-  processMock.mockRestore();
+  processMock.mockClear();
 });

From e33cc3b062ea2b36376d2e8d49403a056ae188a3 Mon Sep 17 00:00:00 2001
From: John Doe <john.doe@example.com>
Date: Wed, 7 Jan 2026 17:03:25 +0100
Subject: [PATCH 07/20] refactor: adjust timeOrigin logic

---
 packages/utils/src/lib/clock-epoch.ts          | 18 ++++++++++++------
 .../utils/src/lib/clock-epoch.unit.test.ts     |  4 ++--
 2 files changed, 14 insertions(+), 8 deletions(-)

diff --git a/packages/utils/src/lib/clock-epoch.ts b/packages/utils/src/lib/clock-epoch.ts
index 1a048059a..f5e5cb96f 100644
--- a/packages/utils/src/lib/clock-epoch.ts
+++ b/packages/utils/src/lib/clock-epoch.ts
@@ -25,6 +25,12 @@ export type EpochClockOptions = {
   pid?: number;
   tid?: number;
 };
+
+type MaybePerformance = typeof performance & {
+  timeOrigin?: number;
+  now?: number;
+};
+
 /**
  * Creates epoch-based clock utility.
  * Epoch time has been the time since January 1, 1970 (UNIX epoch).
@@ -36,12 +42,12 @@ export function epochClock(init: EpochClockOptions = {}) {
   const tid = init.tid ?? threadId;
 
   const timeOriginMs = hasTimeOrigin()
-    ? (performance as { timeOrigin: number | undefined }).timeOrigin
-    : undefined;
+    ? (performance as MaybePerformance).timeOrigin
+    : Date.now();
 
   const epochNowUs = (): Microseconds => {
     if (hasTimeOrigin()) {
-      return msToUs(performance.timeOrigin + performance.now());
+      return msToUs(timeOriginMs + performance.now());
     }
     return msToUs(Date.now());
   };
@@ -51,10 +57,10 @@ export function epochClock(init: EpochClockOptions = {}) {
   const fromEpochMs = msToUs;
 
   const fromPerfMs = (perfMs: Milliseconds): Microseconds => {
-    if (timeOriginMs === undefined) {
-      return epochNowUs() - msToUs(performance.now() - perfMs);
+    if (hasTimeOrigin()) {
+      return msToUs(timeOriginMs + perfMs);
     }
-    return msToUs(timeOriginMs + perfMs);
+    return epochNowUs() - msToUs(performance.now() - perfMs);
   };
 
   const fromEntryStartTimeMs = fromPerfMs;
diff --git a/packages/utils/src/lib/clock-epoch.unit.test.ts b/packages/utils/src/lib/clock-epoch.unit.test.ts
index ad09418fe..eca9c68ac 100644
--- a/packages/utils/src/lib/clock-epoch.unit.test.ts
+++ b/packages/utils/src/lib/clock-epoch.unit.test.ts
@@ -62,7 +62,7 @@ describe('epochClock', () => {
       timeOrigin: undefined,
     });
     const c = epochClock();
-    expect(c.timeOriginMs).toBeUndefined();
+    expect(c.timeOriginMs).toBe(1_000_000);
     expect(c.epochNowUs()).toBe(1_000_000_000); // Date.now() * 1000 when performance unavailable
   });
 
@@ -72,7 +72,7 @@ describe('epochClock', () => {
       timeOrigin: undefined,
     });
     const c = epochClock();
-    expect(c.timeOriginMs).toBeUndefined();
+    expect(c.timeOriginMs).toBe(1_000_000);
     expect(c.fromPerfMs(100)).toBe(500_100_000); // epochNowUs() - msToUs(performance.now() - perfMs)
   });
 

From 26a851a5a23a627ca40ba5060665a4ec1913379e Mon Sep 17 00:00:00 2001
From: John Doe <john.doe@example.com>
Date: Wed, 7 Jan 2026 20:08:00 +0100
Subject: [PATCH 08/20] refactor: remove hasTimeorigin

---
 packages/utils/src/lib/clock-epoch.ts         | 33 +++---------------
 .../utils/src/lib/clock-epoch.unit.test.ts    | 34 -------------------
 .../test-setup/src/lib/process.setup-file.ts  | 11 +++++-
 3 files changed, 15 insertions(+), 63 deletions(-)

diff --git a/packages/utils/src/lib/clock-epoch.ts b/packages/utils/src/lib/clock-epoch.ts
index f5e5cb96f..98c9805a7 100644
--- a/packages/utils/src/lib/clock-epoch.ts
+++ b/packages/utils/src/lib/clock-epoch.ts
@@ -5,13 +5,6 @@ export type Microseconds = number;
 export type Milliseconds = number;
 export type EpochMilliseconds = number;
 
-const hasPerf = (): boolean =>
-  typeof performance !== 'undefined' && typeof performance.now === 'function';
-const hasTimeOrigin = (): boolean =>
-  hasPerf() &&
-  typeof (performance as { timeOrigin: number | undefined }).timeOrigin ===
-    'number';
-
 const msToUs = (ms: number): Microseconds => Math.round(ms * 1000);
 const usToUs = (us: number): Microseconds => Math.round(us);
 
@@ -26,11 +19,6 @@ export type EpochClockOptions = {
   tid?: number;
 };
 
-type MaybePerformance = typeof performance & {
-  timeOrigin?: number;
-  now?: number;
-};
-
 /**
  * Creates epoch-based clock utility.
  * Epoch time has been the time since January 1, 1970 (UNIX epoch).
@@ -41,27 +29,17 @@ export function epochClock(init: EpochClockOptions = {}) {
   const pid = init.pid ?? process.pid;
   const tid = init.tid ?? threadId;
 
-  const timeOriginMs = hasTimeOrigin()
-    ? (performance as MaybePerformance).timeOrigin
-    : Date.now();
+  const timeOriginMs = performance.timeOrigin;
 
-  const epochNowUs = (): Microseconds => {
-    if (hasTimeOrigin()) {
-      return msToUs(timeOriginMs + performance.now());
-    }
-    return msToUs(Date.now());
-  };
+  const epochNowUs = (): Microseconds =>
+    msToUs(timeOriginMs + performance.now());
 
   const fromEpochUs = usToUs;
 
   const fromEpochMs = msToUs;
 
-  const fromPerfMs = (perfMs: Milliseconds): Microseconds => {
-    if (hasTimeOrigin()) {
-      return msToUs(timeOriginMs + perfMs);
-    }
-    return epochNowUs() - msToUs(performance.now() - perfMs);
-  };
+  const fromPerfMs = (perfMs: Milliseconds): Microseconds =>
+    msToUs(timeOriginMs + perfMs);
 
   const fromEntryStartTimeMs = fromPerfMs;
   const fromDateNowMs = fromEpochMs;
@@ -71,7 +49,6 @@ export function epochClock(init: EpochClockOptions = {}) {
     pid,
     tid,
 
-    hasTimeOrigin,
     epochNowUs,
     msToUs,
     usToUs,
diff --git a/packages/utils/src/lib/clock-epoch.unit.test.ts b/packages/utils/src/lib/clock-epoch.unit.test.ts
index eca9c68ac..795eeeca5 100644
--- a/packages/utils/src/lib/clock-epoch.unit.test.ts
+++ b/packages/utils/src/lib/clock-epoch.unit.test.ts
@@ -36,46 +36,12 @@ describe('epochClock', () => {
     );
   });
 
-  it('should return undefined if performance.timeOrigin is NOT present', () => {
-    vi.stubGlobal('performance', {
-      ...performance,
-      timeOrigin: undefined,
-    });
-    const c = epochClock();
-    expect(c.hasTimeOrigin()).toBe(false);
-  });
-
-  it('should return timeorigin if performance.timeOrigin is present', () => {
-    const c = epochClock();
-    expect(c.hasTimeOrigin()).toBe(true);
-  });
-
   it('should support performance clock by default for epochNowUs', () => {
     const c = epochClock();
     expect(c.timeOriginMs).toBe(500_000);
     expect(c.epochNowUs()).toBe(1_000_000_000); // timeOrigin + (Date.now() - timeOrigin) = Date.now()
   });
 
-  it('should fallback to Date clock by if performance clock is not given in epochNowUs', () => {
-    vi.stubGlobal('performance', {
-      ...performance,
-      timeOrigin: undefined,
-    });
-    const c = epochClock();
-    expect(c.timeOriginMs).toBe(1_000_000);
-    expect(c.epochNowUs()).toBe(1_000_000_000); // Date.now() * 1000 when performance unavailable
-  });
-
-  it('should fallback to Date clock by if performance clock is NOT given', () => {
-    vi.stubGlobal('performance', {
-      ...performance,
-      timeOrigin: undefined,
-    });
-    const c = epochClock();
-    expect(c.timeOriginMs).toBe(1_000_000);
-    expect(c.fromPerfMs(100)).toBe(500_100_000); // epochNowUs() - msToUs(performance.now() - perfMs)
-  });
-
   it.each([
     [1_000_000_000, 1_000_000_000],
     [1_001_000_000, 1_001_000_000],
diff --git a/testing/test-setup/src/lib/process.setup-file.ts b/testing/test-setup/src/lib/process.setup-file.ts
index 770e00803..e05a143d5 100644
--- a/testing/test-setup/src/lib/process.setup-file.ts
+++ b/testing/test-setup/src/lib/process.setup-file.ts
@@ -1,13 +1,22 @@
 import process from 'node:process';
+import { threadId } from 'node:worker_threads';
 import { afterEach, beforeEach, vi } from 'vitest';
 
 export const MOCK_PID = 10_001;
+export const MOCK_TID = 1;
+
+// Mock immediately when the setup file loads for default exports using process.pid or threadId
+const processMock = vi.spyOn(process, 'pid', 'get').mockReturnValue(MOCK_PID);
+const threadIdMock = vi
+  .spyOn({ threadId }, 'threadId', 'get')
+  .mockReturnValue(MOCK_TID);
 
-const processMock = vi.spyOn(process, 'pid', 'get');
 beforeEach(() => {
   processMock.mockReturnValue(MOCK_PID);
+  threadIdMock.mockReturnValue(MOCK_TID);
 });
 
 afterEach(() => {
   processMock.mockClear();
+  threadIdMock.mockClear();
 });

From f4848b86e12e379bc1196188b130390c42599004 Mon Sep 17 00:00:00 2001
From: John Doe <john.doe@example.com>
Date: Wed, 7 Jan 2026 20:39:29 +0100
Subject: [PATCH 09/20] refactor: fix unit-test in CI

---
 testing/test-setup/src/lib/process.setup-file.ts | 4 ++--
 1 file changed, 2 insertions(+), 2 deletions(-)

diff --git a/testing/test-setup/src/lib/process.setup-file.ts b/testing/test-setup/src/lib/process.setup-file.ts
index e05a143d5..522829eb2 100644
--- a/testing/test-setup/src/lib/process.setup-file.ts
+++ b/testing/test-setup/src/lib/process.setup-file.ts
@@ -1,5 +1,5 @@
 import process from 'node:process';
-import { threadId } from 'node:worker_threads';
+import workerThreadsModule from 'node:worker_threads';
 import { afterEach, beforeEach, vi } from 'vitest';
 
 export const MOCK_PID = 10_001;
@@ -8,7 +8,7 @@ export const MOCK_TID = 1;
 // Mock immediately when the setup file loads for default exports using process.pid or threadId
 const processMock = vi.spyOn(process, 'pid', 'get').mockReturnValue(MOCK_PID);
 const threadIdMock = vi
-  .spyOn({ threadId }, 'threadId', 'get')
+  .spyOn(workerThreadsModule, 'threadId', 'get')
   .mockReturnValue(MOCK_TID);
 
 beforeEach(() => {

From 173134e91cf4f44bb68c680309e9a92cc860947f Mon Sep 17 00:00:00 2001
From: John Doe <john.doe@example.com>
Date: Wed, 7 Jan 2026 20:53:51 +0100
Subject: [PATCH 10/20] refactor: fix unit-test ci 2

---
 packages/utils/src/lib/clock-epoch.unit.test.ts | 4 +---
 1 file changed, 1 insertion(+), 3 deletions(-)

diff --git a/packages/utils/src/lib/clock-epoch.unit.test.ts b/packages/utils/src/lib/clock-epoch.unit.test.ts
index 795eeeca5..da32b200b 100644
--- a/packages/utils/src/lib/clock-epoch.unit.test.ts
+++ b/packages/utils/src/lib/clock-epoch.unit.test.ts
@@ -9,7 +9,7 @@ describe('epochClock', () => {
   it('should create epoch clock with defaults', () => {
     const c = epochClock();
     expect(c.timeOriginMs).toBe(500_000);
-    expect(c.tid).toBe(1);
+    expect(c.tid).toBeGreaterThan(0);
     expect(c.pid).toBe(10_001);
     expect(typeof c.fromEpochMs).toBe('function');
     expect(typeof c.fromEpochUs).toBe('function');
@@ -22,7 +22,6 @@ describe('epochClock', () => {
     expect(epochClock({ pid: 999 })).toStrictEqual(
       expect.objectContaining({
         pid: 999,
-        tid: 1,
       }),
     );
   });
@@ -30,7 +29,6 @@ describe('epochClock', () => {
   it('should use tid options', () => {
     expect(epochClock({ tid: 888 })).toStrictEqual(
       expect.objectContaining({
-        pid: 10_001,
         tid: 888,
       }),
     );

From 0b1f3358c2784039e94cb017928e92a55e42e88e Mon Sep 17 00:00:00 2001
From: Michael Hladky <10064416+BioPhoton@users.noreply.github.com>
Date: Wed, 7 Jan 2026 21:34:33 +0100
Subject: [PATCH 11/20] Update clock-epoch.unit.test.ts

---
 packages/utils/src/lib/clock-epoch.unit.test.ts | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/packages/utils/src/lib/clock-epoch.unit.test.ts b/packages/utils/src/lib/clock-epoch.unit.test.ts
index da32b200b..06f5b6810 100644
--- a/packages/utils/src/lib/clock-epoch.unit.test.ts
+++ b/packages/utils/src/lib/clock-epoch.unit.test.ts
@@ -9,7 +9,7 @@ describe('epochClock', () => {
   it('should create epoch clock with defaults', () => {
     const c = epochClock();
     expect(c.timeOriginMs).toBe(500_000);
-    expect(c.tid).toBeGreaterThan(0);
+    expect(c.tid).toBe(2);
     expect(c.pid).toBe(10_001);
     expect(typeof c.fromEpochMs).toBe('function');
     expect(typeof c.fromEpochUs).toBe('function');

From 8c2147826670c726b5e473353865a37746dfa970 Mon Sep 17 00:00:00 2001
From: Michael Hladky <10064416+BioPhoton@users.noreply.github.com>
Date: Wed, 7 Jan 2026 21:34:41 +0100
Subject: [PATCH 12/20] Update process.setup-file.ts

---
 testing/test-setup/src/lib/process.setup-file.ts | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/testing/test-setup/src/lib/process.setup-file.ts b/testing/test-setup/src/lib/process.setup-file.ts
index 522829eb2..d11110edf 100644
--- a/testing/test-setup/src/lib/process.setup-file.ts
+++ b/testing/test-setup/src/lib/process.setup-file.ts
@@ -3,7 +3,7 @@ import workerThreadsModule from 'node:worker_threads';
 import { afterEach, beforeEach, vi } from 'vitest';
 
 export const MOCK_PID = 10_001;
-export const MOCK_TID = 1;
+export const MOCK_TID = 2;
 
 // Mock immediately when the setup file loads for default exports using process.pid or threadId
 const processMock = vi.spyOn(process, 'pid', 'get').mockReturnValue(MOCK_PID);

From f192614e19d3d1fafbf742fc843acf20766a45b0 Mon Sep 17 00:00:00 2001
From: John Doe <john.doe@example.com>
Date: Wed, 7 Jan 2026 23:20:34 +0100
Subject: [PATCH 13/20] refactor: add int-test

---
 .../utils/src/lib/clock-epoch.int.test.ts     | 100 ++++++++++++++++++
 .../utils/src/lib/clock-epoch.unit.test.ts    |   6 +-
 .../test-setup/src/lib/process.setup-file.ts  |  15 ++-
 3 files changed, 108 insertions(+), 13 deletions(-)
 create mode 100644 packages/utils/src/lib/clock-epoch.int.test.ts

diff --git a/packages/utils/src/lib/clock-epoch.int.test.ts b/packages/utils/src/lib/clock-epoch.int.test.ts
new file mode 100644
index 000000000..5ca50a46e
--- /dev/null
+++ b/packages/utils/src/lib/clock-epoch.int.test.ts
@@ -0,0 +1,100 @@
+import process from 'node:process';
+import { threadId } from 'node:worker_threads';
+import { describe, expect, it } from 'vitest';
+import { defaultClock, epochClock } from './clock-epoch.js';
+
+describe('epochClock', () => {
+  it('should create epoch clock with defaults', () => {
+    const c = epochClock();
+    expect(c).toStrictEqual(
+      expect.objectContaining({
+        tid: threadId,
+        pid: process.pid,
+        timeOriginMs: performance.timeOrigin,
+      }),
+    );
+    expect(typeof c.fromEpochMs).toBe('function');
+    expect(typeof c.fromEpochUs).toBe('function');
+    expect(typeof c.fromPerfMs).toBe('function');
+    expect(typeof c.fromEntryStartTimeMs).toBe('function');
+    expect(typeof c.fromDateNowMs).toBe('function');
+  });
+
+  it('should support performance clock by default for epochNowUs', () => {
+    const c = epochClock();
+    expect(c.timeOriginMs).toBe(performance.timeOrigin);
+    const nowUs = c.epochNowUs();
+    expect(nowUs).toBe(Math.round(nowUs));
+    const expectedUs = Date.now() * 1000;
+
+    expect(nowUs).toBeGreaterThan(expectedUs - 1000);
+    expect(nowUs).toBeLessThan(expectedUs + 1000);
+  });
+
+  it('should convert epoch milliseconds to microseconds correctly', () => {
+    const c = epochClock();
+    const epochMs = Date.now();
+
+    const result = c.fromEpochMs(epochMs);
+    expect(result).toBe(Math.round(epochMs * 1000));
+    expect(result).toBe(Math.round(result));
+  });
+
+  it('should convert epoch microseconds to microseconds correctly', () => {
+    const c = epochClock();
+    const epochUs = Date.now() * 1000;
+    const expectedUs = Math.round(epochUs);
+
+    const result = c.fromEpochUs(epochUs);
+    expect(result).toBe(expectedUs);
+    expect(result).toBe(Math.round(result));
+  });
+
+  it('should convert performance milliseconds to epoch microseconds correctly', () => {
+    const c = epochClock();
+    const perfMs = performance.now();
+    const expectedUs = Math.round((c.timeOriginMs + perfMs) * 1000);
+
+    const result = c.fromPerfMs(perfMs);
+    expect(result).toBe(expectedUs);
+    expect(result).toBe(Math.round(result));
+  });
+
+  it('should convert entry start time milliseconds to epoch microseconds correctly', () => {
+    const c = epochClock();
+    const entryStartMs = performance.mark('fromPerfMs').startTime;
+    const expectedUs = Math.round((c.timeOriginMs + entryStartMs) * 1000);
+
+    const result = c.fromEntryStartTimeMs(entryStartMs);
+    expect(result).toBe(expectedUs);
+    expect(result).toBe(Math.round(result));
+  });
+
+  it('should convert Date.now milliseconds to epoch microseconds correctly', () => {
+    const c = epochClock();
+    const dateNowMs = Date.now();
+
+    const result = c.fromDateNowMs(dateNowMs);
+    expect(result).toBe(Math.round(dateNowMs * 1000));
+    expect(result).toBe(Math.round(result));
+  });
+});
+
+describe('defaultClock', () => {
+  it('should have valid defaultClock export', () => {
+    const c = defaultClock;
+    expect(c).toStrictEqual(
+      expect.objectContaining({
+        tid: threadId,
+        pid: process.pid,
+        timeOriginMs: performance.timeOrigin,
+      }),
+    );
+
+    expect(typeof c.fromEpochMs).toBe('function');
+    expect(typeof c.fromEpochUs).toBe('function');
+    expect(typeof c.fromPerfMs).toBe('function');
+    expect(typeof c.fromEntryStartTimeMs).toBe('function');
+    expect(typeof c.fromDateNowMs).toBe('function');
+  });
+});
diff --git a/packages/utils/src/lib/clock-epoch.unit.test.ts b/packages/utils/src/lib/clock-epoch.unit.test.ts
index 06f5b6810..dc1eaef5b 100644
--- a/packages/utils/src/lib/clock-epoch.unit.test.ts
+++ b/packages/utils/src/lib/clock-epoch.unit.test.ts
@@ -1,11 +1,7 @@
-import { afterEach, describe, expect, it, vi } from 'vitest';
+import { describe, expect, it } from 'vitest';
 import { defaultClock, epochClock } from './clock-epoch.js';
 
 describe('epochClock', () => {
-  afterEach(() => {
-    vi.unstubAllGlobals();
-  });
-
   it('should create epoch clock with defaults', () => {
     const c = epochClock();
     expect(c.timeOriginMs).toBe(500_000);
diff --git a/testing/test-setup/src/lib/process.setup-file.ts b/testing/test-setup/src/lib/process.setup-file.ts
index d11110edf..714e2aaf9 100644
--- a/testing/test-setup/src/lib/process.setup-file.ts
+++ b/testing/test-setup/src/lib/process.setup-file.ts
@@ -1,22 +1,21 @@
 import process from 'node:process';
-import workerThreadsModule from 'node:worker_threads';
 import { afterEach, beforeEach, vi } from 'vitest';
 
 export const MOCK_PID = 10_001;
 export const MOCK_TID = 2;
 
-// Mock immediately when the setup file loads for default exports using process.pid or threadId
-const processMock = vi.spyOn(process, 'pid', 'get').mockReturnValue(MOCK_PID);
-const threadIdMock = vi
-  .spyOn(workerThreadsModule, 'threadId', 'get')
-  .mockReturnValue(MOCK_TID);
+vi.mock('node:worker_threads', () => ({
+  get threadId() {
+    return MOCK_TID;
+  },
+}));
+
+const processMock = vi.spyOn(process, 'pid', 'get');
 
 beforeEach(() => {
   processMock.mockReturnValue(MOCK_PID);
-  threadIdMock.mockReturnValue(MOCK_TID);
 });
 
 afterEach(() => {
   processMock.mockClear();
-  threadIdMock.mockClear();
 });

From 03a388678ab8fcc1740c4d07e945af4a2add6a59 Mon Sep 17 00:00:00 2001
From: Michael Hladky <10064416+BioPhoton@users.noreply.github.com>
Date: Thu, 8 Jan 2026 12:24:28 +0100
Subject: [PATCH 14/20] Update clock-epoch.int.test.ts

Co-authored-by: Hanna Skryl <80118140+hanna-skryl@users.noreply.github.com>
---
 packages/utils/src/lib/clock-epoch.int.test.ts | 10 +++++-----
 1 file changed, 5 insertions(+), 5 deletions(-)

diff --git a/packages/utils/src/lib/clock-epoch.int.test.ts b/packages/utils/src/lib/clock-epoch.int.test.ts
index 5ca50a46e..420893187 100644
--- a/packages/utils/src/lib/clock-epoch.int.test.ts
+++ b/packages/utils/src/lib/clock-epoch.int.test.ts
@@ -13,11 +13,11 @@ describe('epochClock', () => {
         timeOriginMs: performance.timeOrigin,
       }),
     );
-    expect(typeof c.fromEpochMs).toBe('function');
-    expect(typeof c.fromEpochUs).toBe('function');
-    expect(typeof c.fromPerfMs).toBe('function');
-    expect(typeof c.fromEntryStartTimeMs).toBe('function');
-    expect(typeof c.fromDateNowMs).toBe('function');
+    expect(c.fromEpochMs).toBeFunction();
+    expect(c.fromEpochUs).toBeFunction();
+    expect(c.fromPerfMs).toBeFunction();
+    expect(c.fromEntryStartTimeMs).toBeFunction();
+    expect(c.fromDateNowMs).toBeFunction();
   });
 
   it('should support performance clock by default for epochNowUs', () => {

From 277d329c68a5e96fb646f8f8bba0ed31b8237889 Mon Sep 17 00:00:00 2001
From: Michael Hladky <10064416+BioPhoton@users.noreply.github.com>
Date: Thu, 8 Jan 2026 12:24:39 +0100
Subject: [PATCH 15/20] Update clock-epoch.int.test.ts

Co-authored-by: Hanna Skryl <80118140+hanna-skryl@users.noreply.github.com>
---
 packages/utils/src/lib/clock-epoch.int.test.ts | 3 +--
 1 file changed, 1 insertion(+), 2 deletions(-)

diff --git a/packages/utils/src/lib/clock-epoch.int.test.ts b/packages/utils/src/lib/clock-epoch.int.test.ts
index 420893187..1b20d5ad5 100644
--- a/packages/utils/src/lib/clock-epoch.int.test.ts
+++ b/packages/utils/src/lib/clock-epoch.int.test.ts
@@ -27,8 +27,7 @@ describe('epochClock', () => {
     expect(nowUs).toBe(Math.round(nowUs));
     const expectedUs = Date.now() * 1000;
 
-    expect(nowUs).toBeGreaterThan(expectedUs - 1000);
-    expect(nowUs).toBeLessThan(expectedUs + 1000);
+    expect(nowUs).toBeWithin(expectedUs - 1000, expectedUs + 1000);
   });
 
   it('should convert epoch milliseconds to microseconds correctly', () => {

From 952d8b72a6864dd58a4fdc7e420451ca5c090fab Mon Sep 17 00:00:00 2001
From: Michael Hladky <10064416+BioPhoton@users.noreply.github.com>
Date: Thu, 8 Jan 2026 12:24:49 +0100
Subject: [PATCH 16/20] Update clock-epoch.int.test.ts

Co-authored-by: Hanna Skryl <80118140+hanna-skryl@users.noreply.github.com>
---
 packages/utils/src/lib/clock-epoch.int.test.ts | 10 +++++-----
 1 file changed, 5 insertions(+), 5 deletions(-)

diff --git a/packages/utils/src/lib/clock-epoch.int.test.ts b/packages/utils/src/lib/clock-epoch.int.test.ts
index 1b20d5ad5..18d85b7f7 100644
--- a/packages/utils/src/lib/clock-epoch.int.test.ts
+++ b/packages/utils/src/lib/clock-epoch.int.test.ts
@@ -90,10 +90,10 @@ describe('defaultClock', () => {
       }),
     );
 
-    expect(typeof c.fromEpochMs).toBe('function');
-    expect(typeof c.fromEpochUs).toBe('function');
-    expect(typeof c.fromPerfMs).toBe('function');
-    expect(typeof c.fromEntryStartTimeMs).toBe('function');
-    expect(typeof c.fromDateNowMs).toBe('function');
+    expect(c.fromEpochMs).toBeFunction();
+    expect(c.fromEpochUs).toBeFunction();
+    expect(c.fromPerfMs).toBeFunction();
+    expect(c.fromEntryStartTimeMs).toBeFunction();
+    expect(c.fromDateNowMs).toBeFunction();
   });
 });

From 9487a3fa5ded1c5bb0fc6c75e30a4040c20d0901 Mon Sep 17 00:00:00 2001
From: Michael Hladky <10064416+BioPhoton@users.noreply.github.com>
Date: Thu, 8 Jan 2026 12:25:13 +0100
Subject: [PATCH 17/20] Update clock-epoch.unit.test.ts

Co-authored-by: Hanna Skryl <80118140+hanna-skryl@users.noreply.github.com>
---
 packages/utils/src/lib/clock-epoch.unit.test.ts | 10 +++++-----
 1 file changed, 5 insertions(+), 5 deletions(-)

diff --git a/packages/utils/src/lib/clock-epoch.unit.test.ts b/packages/utils/src/lib/clock-epoch.unit.test.ts
index dc1eaef5b..cc70ecf99 100644
--- a/packages/utils/src/lib/clock-epoch.unit.test.ts
+++ b/packages/utils/src/lib/clock-epoch.unit.test.ts
@@ -7,11 +7,11 @@ describe('epochClock', () => {
     expect(c.timeOriginMs).toBe(500_000);
     expect(c.tid).toBe(2);
     expect(c.pid).toBe(10_001);
-    expect(typeof c.fromEpochMs).toBe('function');
-    expect(typeof c.fromEpochUs).toBe('function');
-    expect(typeof c.fromPerfMs).toBe('function');
-    expect(typeof c.fromEntryStartTimeMs).toBe('function');
-    expect(typeof c.fromDateNowMs).toBe('function');
+    expect(c.fromEpochMs).toBeFunction();
+    expect(c.fromEpochUs).toBeFunction();
+    expect(c.fromPerfMs).toBeFunction();
+    expect(c.fromEntryStartTimeMs).toBeFunction();
+    expect(c.fromDateNowMs).toBeFunction();
   });
 
   it('should use pid options', () => {

From aaac230aceb925ca0b8166e5a815da50f88a524d Mon Sep 17 00:00:00 2001
From: John Doe <john.doe@example.com>
Date: Thu, 8 Jan 2026 17:25:24 +0100
Subject: [PATCH 18/20] refactor: adjust unit test

---
 packages/utils/src/lib/clock-epoch.int.test.ts | 4 ++--
 1 file changed, 2 insertions(+), 2 deletions(-)

diff --git a/packages/utils/src/lib/clock-epoch.int.test.ts b/packages/utils/src/lib/clock-epoch.int.test.ts
index 18d85b7f7..4b3aa0cd3 100644
--- a/packages/utils/src/lib/clock-epoch.int.test.ts
+++ b/packages/utils/src/lib/clock-epoch.int.test.ts
@@ -35,8 +35,8 @@ describe('epochClock', () => {
     const epochMs = Date.now();
 
     const result = c.fromEpochMs(epochMs);
+    expect(result).toBeInteger();
     expect(result).toBe(Math.round(epochMs * 1000));
-    expect(result).toBe(Math.round(result));
   });
 
   it('should convert epoch microseconds to microseconds correctly', () => {
@@ -56,7 +56,7 @@ describe('epochClock', () => {
 
     const result = c.fromPerfMs(perfMs);
     expect(result).toBe(expectedUs);
-    expect(result).toBe(Math.round(result));
+    expect(result).toBeInteger();
   });
 
   it('should convert entry start time milliseconds to epoch microseconds correctly', () => {

From 7d02d56f60367fe062f2ae05112a929e90e78ffa Mon Sep 17 00:00:00 2001
From: John Doe <john.doe@example.com>
Date: Thu, 8 Jan 2026 17:26:32 +0100
Subject: [PATCH 19/20] refactor: adjust types

---
 packages/utils/src/lib/clock-epoch.ts | 1 -
 1 file changed, 1 deletion(-)

diff --git a/packages/utils/src/lib/clock-epoch.ts b/packages/utils/src/lib/clock-epoch.ts
index 98c9805a7..b4380e6af 100644
--- a/packages/utils/src/lib/clock-epoch.ts
+++ b/packages/utils/src/lib/clock-epoch.ts
@@ -3,7 +3,6 @@ import { threadId } from 'node:worker_threads';
 
 export type Microseconds = number;
 export type Milliseconds = number;
-export type EpochMilliseconds = number;
 
 const msToUs = (ms: number): Microseconds => Math.round(ms * 1000);
 const usToUs = (us: number): Microseconds => Math.round(us);

From 04a86551ebb4f597ca762be38b978174a729c15f Mon Sep 17 00:00:00 2001
From: John Doe <john.doe@example.com>
Date: Thu, 8 Jan 2026 17:43:43 +0100
Subject: [PATCH 20/20] refactor: fix timing range test issue in CI

---
 packages/utils/src/lib/clock-epoch.int.test.ts | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/packages/utils/src/lib/clock-epoch.int.test.ts b/packages/utils/src/lib/clock-epoch.int.test.ts
index 4b3aa0cd3..37ca8e546 100644
--- a/packages/utils/src/lib/clock-epoch.int.test.ts
+++ b/packages/utils/src/lib/clock-epoch.int.test.ts
@@ -27,7 +27,7 @@ describe('epochClock', () => {
     expect(nowUs).toBe(Math.round(nowUs));
     const expectedUs = Date.now() * 1000;
 
-    expect(nowUs).toBeWithin(expectedUs - 1000, expectedUs + 1000);
+    expect(nowUs).toBeWithin(expectedUs - 2000, expectedUs + 1000);
   });
 
   it('should convert epoch milliseconds to microseconds correctly', () => {