diff --git a/CHANGES.md b/CHANGES.md
index c3bfb15..16c212f 100644
--- a/CHANGES.md
+++ b/CHANGES.md
@@ -7,7 +7,7 @@ but this file may sometimes contain later improvements (e.g. typo fixes).
 
 ## next (not yet released)
 
-No changes yet.
+- Updated dependencies.
 
 ## v0.8.4 (2024-09-22)
 
diff --git a/package-lock.json b/package-lock.json
index b06896f..d140dbc 100644
--- a/package-lock.json
+++ b/package-lock.json
@@ -14,7 +14,7 @@
 				"undici": "^6.12.0"
 			},
 			"devDependencies": {
-				"@sinonjs/fake-timers": "^12.0.0",
+				"@sinonjs/fake-timers": "^13.0.2",
 				"chai": "^5.1.0",
 				"chai-as-promised": "^8.0.0",
 				"eslint": "^8.57.0",
@@ -370,9 +370,9 @@
 			}
 		},
 		"node_modules/@sinonjs/fake-timers": {
-			"version": "12.0.0",
-			"resolved": "https://registry.npmjs.org/@sinonjs/fake-timers/-/fake-timers-12.0.0.tgz",
-			"integrity": "sha512-bockPohsu/W5uL2w7km2fQcLBm0hi4k2h6Z3/tfzNGQ2BTuFEhJoFrMMpmGAW7zHqop0wtuXDm/WHPNY6JLoHA==",
+			"version": "13.0.2",
+			"resolved": "https://registry.npmjs.org/@sinonjs/fake-timers/-/fake-timers-13.0.2.tgz",
+			"integrity": "sha512-4Bb+oqXZTSTZ1q27Izly9lv8B9dlV61CROxPiVtywwzv5SnytJqhvYe6FclHYuXml4cd1VHPo1zd5PmTeJozvA==",
 			"dev": true,
 			"license": "BSD-3-Clause",
 			"dependencies": {
diff --git a/package.json b/package.json
index 8debc41..7fc80b0 100644
--- a/package.json
+++ b/package.json
@@ -34,7 +34,7 @@
 		"undici": "^6.12.0"
 	},
 	"devDependencies": {
-		"@sinonjs/fake-timers": "^12.0.0",
+		"@sinonjs/fake-timers": "^13.0.2",
 		"chai": "^5.1.0",
 		"chai-as-promised": "^8.0.0",
 		"eslint": "^8.57.0",
diff --git a/test/unit/core.test.js b/test/unit/core.test.js
index 91e419e..9554898 100644
--- a/test/unit/core.test.js
+++ b/test/unit/core.test.js
@@ -378,7 +378,7 @@ describe( 'Session', () => {
 
 			it( 'uses retry options for token request', async () => {
 				const clock = FakeTimers.install();
-				clock.tickAsync( 1000 ); // just so it doesn’t start at 0
+				await clock.tickAsync( 1000 ); // just so it doesn’t start at 0
 
 				try {
 					const expectedParams = {
@@ -406,7 +406,7 @@ describe( 'Session', () => {
 						retryAfterReadonlySeconds: 3,
 						tokenType: 'csrf',
 					} );
-					clock.tickAsync( 5000 );
+					await clock.tickAsync( 5000 );
 					await expect( promise )
 						.to.be.rejectedWith( ApiErrors );
 				} finally {
@@ -638,6 +638,16 @@ describe( 'Session', () => {
 				clock = FakeTimers.install();
 			} );
 			afterEach( () => {
+				/*
+				 * For some reason, since @sinonjs/fake-timers v13,
+				 * the first test in this block which runs (no matter which specific test it is)
+				 * creates a Node-internal afterWriteTick microtask / job
+				 * in between the test returning and the afterEach hook running,
+				 * which fails the countTimers expectation below unless we run it first.
+				 * It’s weird, but at least this keeps the tests working 🤷
+				 */
+				clock.runMicrotasks();
+
 				clock.uninstall();
 				expect( clock.countTimers() ).to.equal( 0 );
 			} );
@@ -651,7 +661,7 @@ describe( 'Session', () => {
 					{ response: { response: true } },
 				] );
 				const promise = session.request( {} );
-				clock.tickAsync( 60000 );
+				await clock.tickAsync( 60000 );
 				const response = await promise;
 				expect( response ).to.eql( { response: true } );
 			} );
@@ -682,7 +692,7 @@ describe( 'Session', () => {
 					{ response: { response: true } },
 				] );
 				const promise = session.request( {} );
-				clock.tickAsync( 65000 );
+				await clock.tickAsync( 65000 );
 				const response = await promise;
 				expect( response ).to.eql( { response: true } );
 			} );
@@ -699,7 +709,7 @@ describe( 'Session', () => {
 					} },
 				] );
 				const promise = session.request( {}, { maxRetriesSeconds: 5 } );
-				clock.tickAsync( 5000 );
+				await clock.tickAsync( 5000 );
 				await expect( promise )
 					.to.be.rejectedWith( ApiErrors );
 			} );
@@ -730,7 +740,7 @@ describe( 'Session', () => {
 					{ response: { response: true } },
 				] );
 				const promise = session.request( {} );
-				clock.tickAsync( 5000 );
+				await clock.tickAsync( 5000 );
 				const response = await promise;
 				expect( response ).to.eql( { response: true } );
 			} );
@@ -741,7 +751,7 @@ describe( 'Session', () => {
 					{ response: { response: true } },
 				] );
 				const promise = session.request( {} );
-				clock.tickAsync( 30000 );
+				await clock.tickAsync( 30000 );
 				const response = await promise;
 				expect( response ).to.eql( { response: true } );
 			} );
@@ -752,7 +762,7 @@ describe( 'Session', () => {
 					{ response: { response: true } },
 				] );
 				const promise = session.request( {}, { retryAfterMaxlagSeconds: 2 } );
-				clock.tickAsync( 2000 );
+				await clock.tickAsync( 2000 );
 				const response = await promise;
 				expect( response ).to.eql( { response: true } );
 			} );
@@ -763,7 +773,7 @@ describe( 'Session', () => {
 					{ response: { response: true } },
 				] );
 				const promise = session.request( {}, { retryAfterReadonlySeconds: 10 } );
-				clock.tickAsync( 10000 );
+				await clock.tickAsync( 10000 );
 				const response = await promise;
 				expect( response ).to.eql( { response: true } );
 			} );