diff --git a/tests/async/parallel.test.ts b/tests/async/parallel.test.ts
index efe0f57d..ba42126b 100644
--- a/tests/async/parallel.test.ts
+++ b/tests/async/parallel.test.ts
@@ -2,13 +2,10 @@ import * as _ from 'radashi'
 import { AggregateError } from 'radashi'
 
 describe('parallel', () => {
-  beforeEach(() => {
-    vi.useFakeTimers({ shouldAdvanceTime: true })
-  })
   test('returns all results from all functions', async () => {
     const [errors, results] = await _.try(async () => {
       return _.parallel(1, _.list(1, 3), async num => {
-        await _.sleep(1000)
+        await _.sleep(0)
         return `hi_${num}`
       })
     })()
@@ -18,7 +15,7 @@ describe('parallel', () => {
   test('throws errors as array of all errors', async () => {
     const [error, results] = await _.try(async () => {
       return _.parallel(1, _.list(1, 3), async num => {
-        await _.sleep(1000)
+        await _.sleep(0)
         if (num === 2) {
           throw new Error('number is 2')
         }
@@ -36,7 +33,7 @@ describe('parallel', () => {
     await _.parallel(3, _.list(1, 14), async () => {
       numInProgress++
       tracking.push(numInProgress)
-      await _.sleep(300)
+      await _.sleep(0)
       numInProgress--
     })
     expect(Math.max(...tracking)).toBe(3)
diff --git a/tests/async/retry.test.ts b/tests/async/retry.test.ts
index acf6ac2e..05658121 100644
--- a/tests/async/retry.test.ts
+++ b/tests/async/retry.test.ts
@@ -5,7 +5,7 @@ const cast = <T = RetryOptions>(value: any): T => value
 
 describe('retry', () => {
   beforeEach(() => {
-    vi.useFakeTimers({ shouldAdvanceTime: true })
+    vi.useFakeTimers()
   })
   test('returns result of given function', async () => {
     const result = await _.retry(cast(null), async _bail => {
@@ -69,7 +69,9 @@ describe('retry', () => {
       const func = async () => {
         throw 'quitagain'
       }
-      await _.retry({ delay: 100 }, func)
+      const promise = _.retry({ delay: 1000, times: 2 }, func)
+      vi.advanceTimersByTimeAsync(1000)
+      await promise
     } catch (err) {
       expect(err).toBe('quitagain')
       return
@@ -80,7 +82,7 @@ describe('retry', () => {
     let count = 0
     let backoffs = 0
     const start = Date.now()
-    await _.retry(
+    const promise = _.retry(
       {
         times: 3,
         backoff: i => {
@@ -95,13 +97,19 @@ describe('retry', () => {
         }
       },
     )
+    // Two async advances for the first two async attempts, each of which are
+    // followed by sleeps
+    vi.advanceTimersToNextTimerAsync()
+    vi.advanceTimersToNextTimerAsync()
+    await promise
+
     const diff = Date.now() - start
     expect(count).toBe(3)
     // Time taken should at least be the
     // total ms backed off. Using exponential
     // backoff (above) 3 times (passing on
     // the third try) that is:
-    //   - 10**1 + 10**2 = 1025
+    //   - 1**10 + 2**10 = 1025
     // The performance typically comes in 1
     // or 2 milliseconds after.
     expect(diff).toBeGreaterThanOrEqual(backoffs)
diff --git a/tests/async/sleep.test.ts b/tests/async/sleep.test.ts
index 805926e3..a4050081 100644
--- a/tests/async/sleep.test.ts
+++ b/tests/async/sleep.test.ts
@@ -2,12 +2,14 @@ import * as _ from 'radashi'
 
 describe('sleep', () => {
   beforeEach(() => {
-    vi.useFakeTimers({ shouldAdvanceTime: true })
+    vi.useFakeTimers()
   })
   test('suspends a thread for a specified number of milliseconds', async () => {
     const ONE_SECOND = 1000
     const before = Date.now()
-    await _.sleep(ONE_SECOND)
+    const promise = _.sleep(ONE_SECOND)
+    vi.advanceTimersToNextTimerAsync()
+    await promise
     const after = Date.now()
     expect(after).toBeGreaterThanOrEqual(before + ONE_SECOND)
   })
diff --git a/tests/curry/debounce.test.ts b/tests/curry/debounce.test.ts
index 559d3b72..e9513882 100644
--- a/tests/curry/debounce.test.ts
+++ b/tests/curry/debounce.test.ts
@@ -9,9 +9,11 @@ describe('debounce', () => {
     func()
     func()
   }
+  const delay = 600
 
   beforeEach(() => {
-    func = _.debounce({ delay: 600 }, mockFunc)
+    vi.useFakeTimers()
+    func = _.debounce({ delay }, mockFunc)
   })
 
   afterEach(() => {
@@ -21,7 +23,7 @@ describe('debounce', () => {
   test('only executes once when called rapidly', async () => {
     runFunc3Times()
     expect(mockFunc).toHaveBeenCalledTimes(0)
-    await _.sleep(610)
+    vi.advanceTimersByTime(delay + 10)
     expect(mockFunc).toHaveBeenCalledTimes(1)
   })
 
@@ -47,7 +49,7 @@ describe('debounce', () => {
     expect(mockFunc).toHaveBeenCalledTimes(1)
     func()
     expect(mockFunc).toHaveBeenCalledTimes(1)
-    await _.sleep(610)
+    vi.advanceTimersByTime(delay + 10)
     expect(mockFunc).toHaveBeenCalledTimes(2)
     func.flush()
     expect(mockFunc).toHaveBeenCalledTimes(3)
@@ -58,11 +60,11 @@ describe('debounce', () => {
     func()
     results.push(func.isPending())
     results.push(func.isPending())
-    await _.sleep(610)
+    vi.advanceTimersByTime(delay + 10)
     results.push(func.isPending())
     func()
     results.push(func.isPending())
-    await _.sleep(610)
+    vi.advanceTimersByTime(delay + 10)
     results.push(func.isPending())
     assert.deepEqual(results, [true, true, false, true, false])
   })
@@ -70,7 +72,7 @@ describe('debounce', () => {
   test('returns if there is any pending invocation when the pending method is called', async () => {
     func()
     func.cancel()
-    await _.sleep(610)
+    vi.advanceTimersByTime(delay + 10)
     expect(mockFunc).toHaveBeenCalledTimes(0)
   })
 })
diff --git a/tests/curry/memo.test.ts b/tests/curry/memo.test.ts
index d76284d3..e2f8d11f 100644
--- a/tests/curry/memo.test.ts
+++ b/tests/curry/memo.test.ts
@@ -24,20 +24,22 @@ describe('memo', () => {
     expect(resultB).not.toBe(resultA)
   })
   test('calls function again when first value expires', async () => {
+    vi.useFakeTimers()
     const func = _.memo(() => new Date().getTime(), {
       ttl: 1,
     })
     const resultA = func()
-    await new Promise(res => setTimeout(res, 100))
+    vi.advanceTimersByTime(100)
     const resultB = func()
     expect(resultA).not.toBe(resultB)
   })
   test('does not call function again when first value has not expired', async () => {
+    vi.useFakeTimers()
     const func = _.memo(() => new Date().getTime(), {
       ttl: 1000,
     })
     const resultA = func()
-    await new Promise(res => setTimeout(res, 100))
+    vi.advanceTimersByTime(100)
     const resultB = func()
     expect(resultA).toBe(resultB)
   })
diff --git a/tests/curry/throttle.test.ts b/tests/curry/throttle.test.ts
index a46e3034..edfacce1 100644
--- a/tests/curry/throttle.test.ts
+++ b/tests/curry/throttle.test.ts
@@ -1,14 +1,20 @@
 import * as _ from 'radashi'
 
 describe('throttle', () => {
+  const interval = 600
+
+  beforeEach(() => {
+    vi.useFakeTimers()
+  })
+
   test('throttles!', async () => {
     let calls = 0
-    const func = _.throttle({ interval: 600 }, () => calls++)
+    const func = _.throttle({ interval }, () => calls++)
     func()
     func()
     func()
     expect(calls).toBe(1)
-    await _.sleep(610)
+    vi.advanceTimersByTime(interval + 10)
     func()
     func()
     func()
@@ -17,7 +23,7 @@ describe('throttle', () => {
 
   test('returns if the throttle is active', async () => {
     const results = []
-    const func = _.throttle({ interval: 600 }, () => {})
+    const func = _.throttle({ interval }, () => {})
     results.push(func.isThrottled())
     func()
     results.push(func.isThrottled())
@@ -25,7 +31,7 @@ describe('throttle', () => {
     results.push(func.isThrottled())
     func()
     results.push(func.isThrottled())
-    await _.sleep(610)
+    vi.advanceTimersByTime(interval + 10)
     results.push(func.isThrottled())
     assert.deepEqual(results, [false, true, true, true, false])
   })