diff --git a/etc/notes/CHANGES_5.0.0.md b/etc/notes/CHANGES_5.0.0.md
index 1b509a68e5e..b0a465e8bad 100644
--- a/etc/notes/CHANGES_5.0.0.md
+++ b/etc/notes/CHANGES_5.0.0.md
@@ -28,3 +28,8 @@ npm install --save snappy@7
 ### Minimum supported Node version
 
 The new minimum supported Node.js version is now 14.20.1.
+
+### Custom Promise library support removed
+
+The MongoClient option `promiseLibrary` along with the `Promise.set` export that allows specifying a custom promise library has been removed.
+This allows the driver to adopt async/await syntax which has [performance benefits](https://v8.dev/blog/fast-async) over manual promise construction.
diff --git a/package-lock.json b/package-lock.json
index 606ff375f8d..e4842fc5c62 100644
--- a/package-lock.json
+++ b/package-lock.json
@@ -32,7 +32,6 @@
         "@types/whatwg-url": "^11.0.0",
         "@typescript-eslint/eslint-plugin": "^5.40.0",
         "@typescript-eslint/parser": "^5.40.0",
-        "bluebird": "^3.7.2",
         "chai": "^4.3.6",
         "chai-subset": "^1.6.0",
         "chalk": "^4.1.2",
@@ -2907,12 +2906,6 @@
         "node": ">=8"
       }
     },
-    "node_modules/bluebird": {
-      "version": "3.7.2",
-      "resolved": "https://registry.npmjs.org/bluebird/-/bluebird-3.7.2.tgz",
-      "integrity": "sha512-XpNj6GDQzdfW+r2Wnn7xiSAd7TM3jzkxGXBGTtWKuSXv1xUV+azxAm8jdWZN06QTQk+2N2XB9jRDkvbmQmcRtg==",
-      "dev": true
-    },
     "node_modules/body-parser": {
       "version": "1.20.1",
       "resolved": "https://registry.npmjs.org/body-parser/-/body-parser-1.20.1.tgz",
@@ -11626,12 +11619,6 @@
       "integrity": "sha512-jDctJ/IVQbZoJykoeHbhXpOlNBqGNcwXJKJog42E5HDPUwQTSdjCHdihjj0DlnheQ7blbT6dHOafNAiS8ooQKA==",
       "dev": true
     },
-    "bluebird": {
-      "version": "3.7.2",
-      "resolved": "https://registry.npmjs.org/bluebird/-/bluebird-3.7.2.tgz",
-      "integrity": "sha512-XpNj6GDQzdfW+r2Wnn7xiSAd7TM3jzkxGXBGTtWKuSXv1xUV+azxAm8jdWZN06QTQk+2N2XB9jRDkvbmQmcRtg==",
-      "dev": true
-    },
     "body-parser": {
       "version": "1.20.1",
       "resolved": "https://registry.npmjs.org/body-parser/-/body-parser-1.20.1.tgz",
diff --git a/package.json b/package.json
index 496968de071..3805fea991d 100644
--- a/package.json
+++ b/package.json
@@ -60,7 +60,6 @@
     "@types/whatwg-url": "^11.0.0",
     "@typescript-eslint/eslint-plugin": "^5.40.0",
     "@typescript-eslint/parser": "^5.40.0",
-    "bluebird": "^3.7.2",
     "chai": "^4.3.6",
     "chai-subset": "^1.6.0",
     "chalk": "^4.1.2",
diff --git a/src/connection_string.ts b/src/connection_string.ts
index a1a177433d5..807457ee61b 100644
--- a/src/connection_string.ts
+++ b/src/connection_string.ts
@@ -25,7 +25,6 @@ import {
   ServerApiVersion
 } from './mongo_client';
 import { MongoLogger, MongoLoggerEnvOptions, MongoLoggerMongoClientOptions } from './mongo_logger';
-import { PromiseProvider } from './promise_provider';
 import { ReadConcern, ReadConcernLevel } from './read_concern';
 import { ReadPreference, ReadPreferenceMode } from './read_preference';
 import type { TagSet } from './sdam/server_description';
@@ -431,10 +430,6 @@ export function parseOptions(
     mongoOptions.dbName = 'test';
   }
 
-  if (options.promiseLibrary) {
-    PromiseProvider.set(options.promiseLibrary);
-  }
-
   validateLoadBalancedOptions(hosts, mongoOptions, isSRV);
 
   if (mongoClient && mongoOptions.autoEncryption) {
@@ -960,10 +955,6 @@ export const OPTIONS = {
       );
     }
   },
-  promiseLibrary: {
-    deprecated: true,
-    type: 'any'
-  },
   promoteBuffers: {
     type: 'boolean'
   },
diff --git a/src/cursor/abstract_cursor.ts b/src/cursor/abstract_cursor.ts
index 8aa59aa651d..95b8bdaef7c 100644
--- a/src/cursor/abstract_cursor.ts
+++ b/src/cursor/abstract_cursor.ts
@@ -17,7 +17,6 @@ import { TODO_NODE_3286, TypedEventEmitter } from '../mongo_types';
 import { executeOperation, ExecutionResult } from '../operations/execute_operation';
 import { GetMoreOperation } from '../operations/get_more';
 import { KillCursorsOperation } from '../operations/kill_cursors';
-import { PromiseProvider } from '../promise_provider';
 import { ReadConcern, ReadConcernLike } from '../read_concern';
 import { ReadPreference, ReadPreferenceLike } from '../read_preference';
 import type { Server } from '../sdam/server';
@@ -297,47 +296,36 @@ export abstract class AbstractCursor<
     return bufferedDocs;
   }
 
-  [Symbol.asyncIterator](): AsyncIterator<TSchema, void> {
-    async function* nativeAsyncIterator(this: AbstractCursor<TSchema>) {
-      if (this.closed) {
-        return;
-      }
+  async *[Symbol.asyncIterator](): AsyncIterator<TSchema, void> {
+    if (this.closed) {
+      return;
+    }
 
-      while (true) {
-        const document = await this.next();
+    while (true) {
+      const document = await this.next();
 
-        // Intentional strict null check, because users can map cursors to falsey values.
-        // We allow mapping to all values except for null.
-        // eslint-disable-next-line no-restricted-syntax
-        if (document === null) {
-          if (!this.closed) {
-            const message =
-              'Cursor returned a `null` document, but the cursor is not exhausted.  Mapping documents to `null` is not supported in the cursor transform.';
+      // Intentional strict null check, because users can map cursors to falsey values.
+      // We allow mapping to all values except for null.
+      // eslint-disable-next-line no-restricted-syntax
+      if (document === null) {
+        if (!this.closed) {
+          const message =
+            'Cursor returned a `null` document, but the cursor is not exhausted.  Mapping documents to `null` is not supported in the cursor transform.';
 
-            await cleanupCursorAsync(this, { needsToEmitClosed: true }).catch(() => null);
+          await cleanupCursorAsync(this, { needsToEmitClosed: true }).catch(() => null);
 
-            throw new MongoAPIError(message);
-          }
-          break;
-        }
-
-        yield document;
-
-        if (this[kId] === Long.ZERO) {
-          // Cursor exhausted
-          break;
+          throw new MongoAPIError(message);
         }
+        break;
       }
-    }
 
-    const iterator = nativeAsyncIterator.call(this);
+      yield document;
 
-    if (PromiseProvider.get() == null) {
-      return iterator;
+      if (this[kId] === Long.ZERO) {
+        // Cursor exhausted
+        break;
+      }
     }
-    return {
-      next: () => maybeCallback(() => iterator.next(), null)
-    };
   }
 
   stream(options?: CursorStreamOptions): Readable & AsyncIterable<TSchema> {
diff --git a/src/index.ts b/src/index.ts
index 68fdd89b422..75d9b9c7dec 100644
--- a/src/index.ts
+++ b/src/index.ts
@@ -16,7 +16,6 @@ import { GridFSBucketWriteStream } from './gridfs/upload';
 import { Logger } from './logger';
 import { MongoClient } from './mongo_client';
 import { CancellationToken } from './mongo_types';
-import { PromiseProvider } from './promise_provider';
 import { ClientSession } from './sessions';
 
 /** @internal */
@@ -100,9 +99,6 @@ export {
   UnorderedBulkOperation
 };
 
-// Deprecated, remove in next major
-export { PromiseProvider as Promise };
-
 // enums
 export { BatchType } from './bulk/common';
 export { GSSAPICanonicalizationValue } from './cmap/auth/gssapi';
diff --git a/src/mongo_client.ts b/src/mongo_client.ts
index 4d94d87747e..63b46cf9ecb 100644
--- a/src/mongo_client.ts
+++ b/src/mongo_client.ts
@@ -228,11 +228,6 @@ export interface MongoClientOptions extends BSONSerializeOptions, SupportedNodeC
   forceServerObjectId?: boolean;
   /** A primary key factory function for generation of custom `_id` keys */
   pkFactory?: PkFactory;
-  /**
-   * A Promise library class the application wishes to use such as Bluebird, must be ES6 compatible
-   * @deprecated Setting a custom promise library is deprecated the next major version will use the global Promise constructor only.
-   */
-  promiseLibrary?: any;
   /** The logging level */
   loggerLevel?: LegacyLoggerLevel;
   /** Custom logger object */
@@ -743,7 +738,6 @@ export interface MongoOptions
         | 'monitorCommands'
         | 'noDelay'
         | 'pkFactory'
-        | 'promiseLibrary'
         | 'raw'
         | 'replicaSet'
         | 'retryReads'
diff --git a/src/promise_provider.ts b/src/promise_provider.ts
deleted file mode 100644
index eb9a28c756e..00000000000
--- a/src/promise_provider.ts
+++ /dev/null
@@ -1,56 +0,0 @@
-import { MongoInvalidArgumentError } from './error';
-
-/** @internal */
-const kPromise = Symbol('promise');
-
-interface PromiseStore {
-  [kPromise]: PromiseConstructor | null;
-}
-
-const store: PromiseStore = {
-  [kPromise]: null
-};
-
-/**
- * Global promise store allowing user-provided promises
- * @deprecated Setting a custom promise library is deprecated the next major version will use the global Promise constructor only.
- * @public
- */
-export class PromiseProvider {
-  /**
-   * Validates the passed in promise library
-   * @deprecated Setting a custom promise library is deprecated the next major version will use the global Promise constructor only.
-   */
-  static validate(lib: unknown): lib is PromiseConstructor {
-    if (typeof lib !== 'function')
-      throw new MongoInvalidArgumentError(`Promise must be a function, got ${lib}`);
-    return !!lib;
-  }
-
-  /**
-   * Sets the promise library
-   * @deprecated Setting a custom promise library is deprecated the next major version will use the global Promise constructor only.
-   */
-  static set(lib: PromiseConstructor | null): void {
-    // eslint-disable-next-line no-restricted-syntax
-    if (lib === null) {
-      // Check explicitly against null since `.set()` (no args) should fall through to validate
-      store[kPromise] = null;
-      return;
-    }
-
-    if (!PromiseProvider.validate(lib)) {
-      // validate
-      return;
-    }
-    store[kPromise] = lib;
-  }
-
-  /**
-   * Get the stored promise library, or resolves passed in
-   * @deprecated Setting a custom promise library is deprecated the next major version will use the global Promise constructor only.
-   */
-  static get(): PromiseConstructor | null {
-    return store[kPromise];
-  }
-}
diff --git a/src/sessions.ts b/src/sessions.ts
index 803a174dec5..1774f7c7806 100644
--- a/src/sessions.ts
+++ b/src/sessions.ts
@@ -25,7 +25,6 @@ import type { MongoClient, MongoOptions } from './mongo_client';
 import { TypedEventEmitter } from './mongo_types';
 import { executeOperation } from './operations/execute_operation';
 import { RunAdminCommandOperation } from './operations/run_command';
-import { PromiseProvider } from './promise_provider';
 import { ReadConcernLevel } from './read_concern';
 import { ReadPreference } from './read_preference';
 import { _advanceClusterTime, ClusterTime, TopologyType } from './sdam/common';
@@ -605,8 +604,7 @@ function attemptTransaction<TSchema>(
   try {
     promise = fn(session);
   } catch (err) {
-    const PromiseConstructor = PromiseProvider.get() ?? Promise;
-    promise = PromiseConstructor.reject(err);
+    promise = Promise.reject(err);
   }
 
   if (!isPromiseLike(promise)) {
diff --git a/src/utils.ts b/src/utils.ts
index f0784214204..f6027c8e58b 100644
--- a/src/utils.ts
+++ b/src/utils.ts
@@ -23,7 +23,6 @@ import type { Explain } from './explain';
 import type { MongoClient } from './mongo_client';
 import type { CommandOperationOptions, OperationParent } from './operations/command';
 import type { Hint, OperationOptions } from './operations/operation';
-import { PromiseProvider } from './promise_provider';
 import { ReadConcern } from './read_concern';
 import { ReadPreference } from './read_preference';
 import { ServerType } from './sdam/common';
@@ -445,17 +444,9 @@ export function maybeCallback<T>(
   promiseFn: () => Promise<T>,
   callback?: Callback<T> | null
 ): Promise<T> | void {
-  const PromiseConstructor = PromiseProvider.get();
-
   const promise = promiseFn();
   if (callback == null) {
-    if (PromiseConstructor == null) {
-      return promise;
-    } else {
-      return new PromiseConstructor((resolve, reject) => {
-        promise.then(resolve, reject);
-      });
-    }
+    return promise;
   }
 
   promise.then(
diff --git a/test/integration/collection-management/promise_collection_db_management.test.ts b/test/integration/collection-management/promise_collection_db_management.test.ts
index b7f789ed22a..8277ccdec90 100644
--- a/test/integration/collection-management/promise_collection_db_management.test.ts
+++ b/test/integration/collection-management/promise_collection_db_management.test.ts
@@ -1,9 +1,5 @@
 import { assert as test, setupDatabase } from '../shared';
 
-class CustomPromise extends Promise<void> {}
-// @ts-expect-error: Dynamic addition to detect custom promise
-CustomPromise.prototype.isCustomMongo = true;
-
 describe('Collection Management and Db Management (promise tests)', function () {
   before(function () {
     return setupDatabase(this.configuration);
diff --git a/test/integration/crud/promise_stats.test.js b/test/integration/crud/promise_stats.test.js
index 1de801a2ac7..c41352a0253 100644
--- a/test/integration/crud/promise_stats.test.js
+++ b/test/integration/crud/promise_stats.test.js
@@ -3,9 +3,6 @@
 const { assert: test, setupDatabase } = require('../shared');
 const f = require('util').format;
 
-class CustomPromise extends Promise {}
-CustomPromise.prototype.isCustomMongo = true;
-
 describe('stats', function () {
   before(function () {
     return setupDatabase(this.configuration);
diff --git a/test/integration/mongodb-handshake/promise_handshake.test.js b/test/integration/mongodb-handshake/promise_handshake.test.js
index 1824a8ab77f..ac4abfafbce 100644
--- a/test/integration/mongodb-handshake/promise_handshake.test.js
+++ b/test/integration/mongodb-handshake/promise_handshake.test.js
@@ -3,9 +3,6 @@ const { assert: test, setupDatabase } = require('../shared');
 const f = require('util').format;
 const { LEGACY_HELLO_COMMAND } = require('../../../src/constants');
 
-class CustomPromise extends Promise {}
-CustomPromise.prototype.isCustomMongo = true;
-
 describe('Handshake', function () {
   before(function () {
     return setupDatabase(this.configuration);
diff --git a/test/integration/node-specific/cursor_async_iterator.test.js b/test/integration/node-specific/cursor_async_iterator.test.js
index 944362bf346..4635c414541 100644
--- a/test/integration/node-specific/cursor_async_iterator.test.js
+++ b/test/integration/node-specific/cursor_async_iterator.test.js
@@ -1,9 +1,6 @@
 'use strict';
 
 const { expect } = require('chai');
-const Sinon = require('sinon');
-const { Promise: BluebirdPromise } = require('bluebird');
-const { PromiseProvider } = require('../../../src/promise_provider');
 
 describe('Cursor Async Iterator Tests', function () {
   context('default promise library', function () {
@@ -83,58 +80,4 @@ describe('Cursor Async Iterator Tests', function () {
       expect(count).to.equal(1);
     });
   });
-  context('custom promise library', () => {
-    let client, collection, promiseSpy;
-    beforeEach(async function () {
-      promiseSpy = Sinon.spy(BluebirdPromise.prototype, 'then');
-      client = this.configuration.newClient({}, { promiseLibrary: BluebirdPromise });
-
-      const connectPromise = client.connect();
-      expect(connectPromise).to.be.instanceOf(BluebirdPromise);
-      await connectPromise;
-      const docs = Array.from({ length: 1 }).map((_, index) => ({ foo: index, bar: 1 }));
-
-      collection = client.db(this.configuration.db).collection('async_cursor_tests');
-
-      await collection.deleteMany({});
-      await collection.insertMany(docs);
-      await client.close();
-    });
-
-    beforeEach(async function () {
-      client = this.configuration.newClient();
-      await client.connect();
-      collection = client.db(this.configuration.db).collection('async_cursor_tests');
-    });
-
-    afterEach(() => {
-      promiseSpy.restore();
-      PromiseProvider.set(null);
-      return client.close();
-    });
-
-    it('should properly use custom promise', async function () {
-      const cursor = collection.find();
-      const countBeforeIteration = promiseSpy.callCount;
-      for await (const doc of cursor) {
-        expect(doc).to.exist;
-      }
-      expect(countBeforeIteration).to.not.equal(promiseSpy.callCount);
-      expect(promiseSpy.called).to.equal(true);
-    });
-
-    it('should properly use custom promise manual iteration', async function () {
-      const cursor = collection.find();
-
-      const iterator = cursor[Symbol.asyncIterator]();
-      let isDone;
-      do {
-        const promiseFromIterator = iterator.next();
-        expect(promiseFromIterator).to.be.instanceOf(BluebirdPromise);
-        const { done, value } = await promiseFromIterator;
-        if (done) expect(value).to.be.a('undefined');
-        isDone = done;
-      } while (!isDone);
-    });
-  });
 });
diff --git a/test/integration/node-specific/custom_promise_library.test.js b/test/integration/node-specific/custom_promise_library.test.js
deleted file mode 100644
index 3a93bb28118..00000000000
--- a/test/integration/node-specific/custom_promise_library.test.js
+++ /dev/null
@@ -1,80 +0,0 @@
-'use strict';
-
-const { once } = require('events');
-const { expect } = require('chai');
-const { PromiseProvider } = require('../../../src/promise_provider');
-const { MongoClient } = require('../../../src/mongo_client');
-
-class CustomPromise extends Promise {}
-CustomPromise.prototype.isCustomMongo = true;
-
-describe('Optional PromiseLibrary', function () {
-  beforeEach(() => {
-    PromiseProvider.set(null);
-  });
-
-  afterEach(() => {
-    PromiseProvider.set(null);
-  });
-
-  it('should initially be set to null', () => {
-    expect(PromiseProvider.get()).to.be.null;
-  });
-
-  it('should allow passing null to .set() to clear the set promise', () => {
-    PromiseProvider.set(Promise);
-    expect(PromiseProvider.get()).to.equal(Promise);
-    expect(() => PromiseProvider.set(null)).to.not.throw();
-    expect(PromiseProvider.get()).to.be.null;
-  });
-
-  it('should emit a deprecation warning when a promiseLibrary is set', async () => {
-    const willEmitWarning = once(process, 'warning');
-    new MongoClient('mongodb://iLoveJavascript', { promiseLibrary: () => {} });
-    const [warning] = await willEmitWarning;
-    expect(warning).to.have.property('message', 'promiseLibrary is a deprecated option');
-  });
-
-  it('should correctly implement custom dependency-less promise', function (done) {
-    const getCustomPromise = v => new CustomPromise(resolve => resolve(v));
-    const getNativePromise = v => new Promise(resolve => resolve(v));
-    expect(getNativePromise()).to.not.have.property('isCustomMongo');
-    expect(getCustomPromise()).to.have.property('isCustomMongo');
-    expect(getNativePromise()).to.have.property('then');
-    expect(getCustomPromise()).to.have.property('then');
-    done();
-  });
-
-  it('should have cursor return native promise', function (done) {
-    const configuration = this.configuration;
-    const client = this.configuration.newClient({ w: 1 }, { maxPoolSize: 1 });
-    client.connect((err, client) => {
-      expect(err).to.not.exist;
-      const db = client.db(configuration.db);
-      const collection = db.collection('test');
-      const cursor = collection.find({});
-      const isPromise = cursor.toArray();
-      expect(isPromise).to.not.have.property('isCustomMongo');
-      expect(isPromise).to.have.property('then');
-      isPromise.then(() => client.close(done));
-    });
-  });
-
-  it('should have cursor return custom promise from new client options', function (done) {
-    const configuration = this.configuration;
-    const client = this.configuration.newClient(
-      { w: 1 },
-      { maxPoolSize: 1, promiseLibrary: CustomPromise }
-    );
-    client.connect((err, client) => {
-      const db = client.db(configuration.db);
-      expect(err).to.not.exist;
-      const collection = db.collection('test');
-      const cursor = collection.find({});
-      const isPromise = cursor.toArray();
-      expect(isPromise).to.have.property('isCustomMongo');
-      expect(isPromise).to.have.property('then');
-      isPromise.then(() => client.close(done));
-    });
-  });
-});
diff --git a/test/integration/server_write_command.js b/test/integration/server_write_command.js
deleted file mode 100644
index 7355c24e6c7..00000000000
--- a/test/integration/server_write_command.js
+++ /dev/null
@@ -1,33 +0,0 @@
-'use strict';
-const { setupDatabase } = require('./shared');
-
-class CustomPromise extends Promise {}
-CustomPromise.prototype.isCustomMongo = true;
-
-describe('Server Write Command', function () {
-  before(function () {
-    return setupDatabase(this.configuration);
-  });
-
-  it('Should correctly catch command error using Promise', {
-    metadata: {
-      requires: {
-        topology: ['single']
-      }
-    },
-
-    test: function (done) {
-      const client = this.configuration.newClient({ maxPoolSize: 5 });
-      client
-        .db(this.configuration.db)
-        .command({ nosuchcommand: true })
-        .then(function () {})
-        .catch(function () {
-          // Execute close using promise
-          client.close().then(function () {
-            done();
-          });
-        });
-    }
-  });
-});
diff --git a/test/types/mongodb.test-d.ts b/test/types/mongodb.test-d.ts
index fe75b1e223b..eb9164659e4 100644
--- a/test/types/mongodb.test-d.ts
+++ b/test/types/mongodb.test-d.ts
@@ -22,20 +22,10 @@ expectDeprecated(Db.prototype.unref);
 expectDeprecated(MongoDBDriver.ObjectID);
 expectNotDeprecated(MongoDBDriver.ObjectId);
 
-// We cannot attach a deprecation tag to an export
-// We tried export const Promise = PromiseProvider;
-// but then api-extractor claims PromiseProvider is not exported
-// Instead we've deprecated all the methods on the class
-expectNotDeprecated(MongoDBDriver.Promise);
-expectDeprecated(MongoDBDriver.Promise.validate);
-expectDeprecated(MongoDBDriver.Promise.get);
-expectDeprecated(MongoDBDriver.Promise.set);
-
 declare const options: MongoDBDriver.MongoClientOptions;
 expectDeprecated(options.w);
 expectDeprecated(options.journal);
 expectDeprecated(options.wtimeoutMS);
-expectDeprecated(options.promiseLibrary);
 expectNotDeprecated(options.writeConcern);
 expectType<WriteConcernSettings | WriteConcern | undefined>(options.writeConcern);
 
diff --git a/test/unit/index.test.ts b/test/unit/index.test.ts
index 2ebd2293c94..115a2363293 100644
--- a/test/unit/index.test.ts
+++ b/test/unit/index.test.ts
@@ -102,7 +102,6 @@ const EXPECTED_EXPORTS = [
   'ObjectID',
   'OrderedBulkOperation',
   'ProfilingLevel',
-  'Promise',
   'ReadConcern',
   'ReadConcernLevel',
   'ReadPreference',
diff --git a/test/unit/utils.test.ts b/test/unit/utils.test.ts
index fccfa524732..205f8c7bbae 100644
--- a/test/unit/utils.test.ts
+++ b/test/unit/utils.test.ts
@@ -1,9 +1,8 @@
-import { Promise as BluebirdPromise } from 'bluebird';
 import { expect } from 'chai';
 
 import { LEGACY_HELLO_COMMAND } from '../../src/constants';
 import { MongoRuntimeError } from '../../src/error';
-import { ObjectId, Promise as PromiseProvider } from '../../src/index';
+import { ObjectId } from '../../src/index';
 import {
   BufferPool,
   compareObjectId,
@@ -775,44 +774,6 @@ describe('driver utils', function () {
         expect(await result).to.equal(2);
       });
     });
-
-    describe('when a custom promise constructor is set', () => {
-      beforeEach(() => {
-        PromiseProvider.set(BluebirdPromise);
-      });
-
-      afterEach(() => {
-        PromiseProvider.set(null);
-      });
-
-      it('should return the custom promise if no callback is provided', async () => {
-        const superPromiseSuccess = Promise.resolve(2);
-        const result = maybeCallback(() => superPromiseSuccess);
-        expect(result).to.not.equal(superPromiseSuccess);
-        expect(result).to.be.instanceOf(BluebirdPromise);
-      });
-
-      it('should return a rejected custom promise instance if promiseFn rejects', async () => {
-        const superPromiseFailure = Promise.reject(new Error('ah!'));
-        const result = maybeCallback(() => superPromiseFailure);
-        expect(result).to.not.equal(superPromiseFailure);
-        expect(result).to.be.instanceOf(BluebirdPromise);
-        // @ts-expect-error: There is no overload to change the return type not be nullish,
-        // and we do not want to add one in fear of making it too easy to neglect adding the callback argument
-        expect(await result.catch(e => e)).to.have.property('message', 'ah!');
-      });
-
-      it('should return void even if a custom promise is set and a callback is provided', async () => {
-        const superPromiseSuccess = Promise.resolve(2);
-        const result = maybeCallback(
-          () => superPromiseSuccess,
-          () => {
-            // ignore
-          }
-        );
-        expect(result).to.be.undefined;
-      });
-    });
   });
 
   describe('compareObjectId()', () => {