diff --git a/src/task_queue/array_queue.ts b/src/task_queue/array_queue.ts
index 6d215152..866b8881 100644
--- a/src/task_queue/array_queue.ts
+++ b/src/task_queue/array_queue.ts
@@ -1,4 +1,4 @@
-import assert from 'node:assert';
+import * as assert from 'node:assert';
 
 import type { TaskQueue, Task } from '.';
 
diff --git a/src/task_queue/fixed_queue.ts b/src/task_queue/fixed_queue.ts
index 80213dcb..ff1270a7 100644
--- a/src/task_queue/fixed_queue.ts
+++ b/src/task_queue/fixed_queue.ts
@@ -3,7 +3,7 @@
  * License: MIT License
  * Source: https://github.com/nodejs/node/blob/de7b37880f5a541d5f874c1c2362a65a4be76cd0/lib/internal/fixed_queue.js
  */
-import assert from 'node:assert';
+import * as assert from 'node:assert';
 import type { Task } from './common';
 import { TaskQueue } from '.';
 // Currently optimal queue size, tested on V8 6.0 - 6.6. Must be power of two.
diff --git a/src/worker.ts b/src/worker.ts
index 10f306ca..d43d5363 100644
--- a/src/worker.ts
+++ b/src/worker.ts
@@ -55,16 +55,23 @@ async function getHandler (filename : string, name : string) : Promise<Function
     // With our current set of TypeScript options, this is transpiled to
     // `require(filename)`.
     handler = await import(filename);
-    if (typeof handler !== 'function') {
+
+    if (name?.length > 0) {
+      handler = await ((handler as any)[name]);
+    } else if (typeof handler !== 'function') {
       handler = await ((handler as any)[name]);
     }
   } catch {}
+
   if (typeof handler !== 'function') {
     handler = await getImportESM()(pathToFileURL(filename).href);
-    if (typeof handler !== 'function') {
+    if (name?.length > 0) {
+      handler = await ((handler as any)[name]);
+    } else if (typeof handler !== 'function') {
       handler = await ((handler as any)[name]);
     }
   }
+
   if (typeof handler !== 'function') {
     return null;
   }
diff --git a/src/worker_pool/base.ts b/src/worker_pool/base.ts
index 9c19c1ea..3d592156 100644
--- a/src/worker_pool/base.ts
+++ b/src/worker_pool/base.ts
@@ -1,4 +1,4 @@
-import assert from 'node:assert';
+import * as assert from 'node:assert';
 
 export abstract class AsynchronouslyCreatedResource {
     onreadyListeners : (() => void)[] | null = [];
diff --git a/src/worker_pool/index.ts b/src/worker_pool/index.ts
index 075bfaaa..fdb6a9c8 100644
--- a/src/worker_pool/index.ts
+++ b/src/worker_pool/index.ts
@@ -1,6 +1,6 @@
 import { Worker, MessagePort, receiveMessageOnPort, WorkerOptions, Transferable } from 'node:worker_threads';
 import { createHistogram, RecordableHistogram } from 'node:perf_hooks';
-import assert from 'node:assert';
+import * as assert from 'node:assert';
 
 import { RequestMessage, ResponseMessage, StartupMessage } from '../types';
 import { Errors } from '../errors';
diff --git a/test/abort-task.test.ts b/test/abort-task.test.ts
index f56cf7b0..d298da48 100644
--- a/test/abort-task.test.ts
+++ b/test/abort-task.test.ts
@@ -1,5 +1,5 @@
 import { test } from 'node:test';
-import assert from 'node:assert/strict';
+import * as assert from 'node:assert/strict';
 import { EventEmitter } from 'node:events';
 import Piscina from '..';
 import { resolve } from 'path';
diff --git a/test/async-context.test.ts b/test/async-context.test.ts
index 5a3727b4..0b1a49cc 100644
--- a/test/async-context.test.ts
+++ b/test/async-context.test.ts
@@ -1,4 +1,4 @@
-import assert from 'node:assert/strict';
+import * as assert from 'node:assert/strict';
 import { test } from 'node:test';
 import { resolve } from 'node:path';
 import { createHook, executionAsyncId } from 'node:async_hooks';
diff --git a/test/atomics-optimization.test.ts b/test/atomics-optimization.test.ts
index 1aac801c..917266d7 100644
--- a/test/atomics-optimization.test.ts
+++ b/test/atomics-optimization.test.ts
@@ -1,4 +1,4 @@
-import assert from 'node:assert/strict';
+import * as assert from 'node:assert/strict';
 import { test } from 'node:test';
 import { resolve } from 'node:path';
 import Piscina from '..';
diff --git a/test/console-log.test.ts b/test/console-log.test.ts
index 357effe7..9a910408 100644
--- a/test/console-log.test.ts
+++ b/test/console-log.test.ts
@@ -1,4 +1,4 @@
-import assert from 'node:assert/strict';
+import * as assert from 'node:assert/strict';
 import { resolve } from 'node:path';
 import { spawn } from 'node:child_process';
 import { test } from 'node:test';
diff --git a/test/fixed-queue.test.ts b/test/fixed-queue.test.ts
index 23bf532a..e8a33e60 100644
--- a/test/fixed-queue.test.ts
+++ b/test/fixed-queue.test.ts
@@ -1,4 +1,4 @@
-import assert from 'node:assert';
+import * as assert from 'node:assert/strict';
 import { test } from 'node:test';
 import { resolve } from 'node:path';
 import { kQueueOptions } from '../dist/symbols';
diff --git a/test/fixtures/cjs-default.js b/test/fixtures/cjs-default.js
new file mode 100644
index 00000000..6d7c3206
--- /dev/null
+++ b/test/fixtures/cjs-default.js
@@ -0,0 +1,3 @@
+module.exports.default = async function generate() {
+  return 42;
+}
\ No newline at end of file
diff --git a/test/fixtures/move.ts b/test/fixtures/move.ts
index 0c3ee096..91b35947 100644
--- a/test/fixtures/move.ts
+++ b/test/fixtures/move.ts
@@ -1,10 +1,10 @@
-import assert from 'node:assert';
+import * as assert from 'node:assert/strict';
 import { types } from 'node:util';
 import Piscina from '../..';
 
 export default function (moved) {
   if (moved !== undefined) {
-    assert(types.isAnyArrayBuffer(moved));
+    assert.ok(types.isAnyArrayBuffer(moved));
   }
   return Piscina.move(new ArrayBuffer(10));
 }
diff --git a/test/fixtures/notify-then-sleep-or.ts b/test/fixtures/notify-then-sleep-or.ts
index 3b417af9..5fc7b562 100644
--- a/test/fixtures/notify-then-sleep-or.ts
+++ b/test/fixtures/notify-then-sleep-or.ts
@@ -1,5 +1,5 @@
 // Set the index-th bith in i32array[0], then wait for it to be un-set again.
-module.exports = function ({ i32array, index }) {
+export default function ({ i32array, index }) {
   Atomics.or(i32array, 0, 1 << index);
   Atomics.notify(i32array, 0, Infinity);
   do {
diff --git a/test/fixtures/wait-for-notify.ts b/test/fixtures/wait-for-notify.ts
index 1a47fcb5..968e9b0b 100644
--- a/test/fixtures/wait-for-notify.ts
+++ b/test/fixtures/wait-for-notify.ts
@@ -1,4 +1,4 @@
-module.exports = function (i32array) {
+export default function (i32array) {
   Atomics.wait(i32array, 0, 0);
   Atomics.store(i32array, 0, -1);
   Atomics.notify(i32array, 0, Infinity);
diff --git a/test/fixtures/wait-for-others.ts b/test/fixtures/wait-for-others.ts
index 96bd2c93..05dc2011 100644
--- a/test/fixtures/wait-for-others.ts
+++ b/test/fixtures/wait-for-others.ts
@@ -1,6 +1,6 @@
 import { threadId } from 'worker_threads';
 
-module.exports = async function ([i32array, n]) {
+export default async function ([i32array, n]) {
   Atomics.add(i32array, 0, 1);
   Atomics.notify(i32array, 0, Infinity);
   let lastSeenValue;
diff --git a/test/generics.test.ts b/test/generics.test.ts
index 4bb5dd04..4d11613b 100644
--- a/test/generics.test.ts
+++ b/test/generics.test.ts
@@ -1,4 +1,4 @@
-import assert from 'node:assert/strict';
+import * as assert from 'node:assert/strict';
 import { resolve } from 'node:path';
 import { test } from 'node:test';
 import Piscina from '../dist';
diff --git a/test/histogram.test.ts b/test/histogram.test.ts
index 3cc1b876..26f1b696 100644
--- a/test/histogram.test.ts
+++ b/test/histogram.test.ts
@@ -1,4 +1,4 @@
-import assert from 'node:assert/strict';
+import * as assert from 'node:assert/strict';
 import { resolve } from 'node:path';
 import { test } from 'node:test';
 import type { TestContext } from 'node:test';
diff --git a/test/idle-timeout.test.ts b/test/idle-timeout.test.ts
index 6174bc60..b22280ec 100644
--- a/test/idle-timeout.test.ts
+++ b/test/idle-timeout.test.ts
@@ -1,4 +1,4 @@
-import assert from 'node:assert/strict';
+import * as assert from 'node:assert/strict';
 import { test } from 'node:test';
 import { resolve } from 'node:path';
 import { promisify } from 'node:util';
diff --git a/test/issue-513.test.ts b/test/issue-513.test.ts
index 36a0163a..d4899fc2 100644
--- a/test/issue-513.test.ts
+++ b/test/issue-513.test.ts
@@ -1,4 +1,4 @@
-import assert from 'node:assert';
+import * as assert from 'node:assert/strict';
 import { test } from 'node:test';
 import { resolve } from 'node:path';
 import Piscina from '..';
diff --git a/test/load-with-esm.test.ts b/test/load-with-esm.test.ts
index fa5ba723..71d43d4a 100644
--- a/test/load-with-esm.test.ts
+++ b/test/load-with-esm.test.ts
@@ -1,4 +1,4 @@
-import assert from 'node:assert/strict';
+import * as assert from 'node:assert/strict';
 import { test } from 'node:test';
 
 
diff --git a/test/messages.test.ts b/test/messages.test.ts
index 66b78b8e..fd66af7e 100644
--- a/test/messages.test.ts
+++ b/test/messages.test.ts
@@ -1,4 +1,4 @@
-import assert from 'node:assert/strict';
+import * as assert from 'node:assert/strict';
 import { test } from 'node:test';
 import { resolve } from 'node:path';
 import { once } from 'node:events';
diff --git a/test/move-test.test.ts b/test/move-test.test.ts
index f6ff2655..39f7eb6f 100644
--- a/test/move-test.test.ts
+++ b/test/move-test.test.ts
@@ -1,4 +1,4 @@
-import assert from 'node:assert';
+import * as assert from 'node:assert/strict';
 import { test } from 'node:test';
 import { types } from 'node:util';
 import { MessageChannel, MessagePort } from 'node:worker_threads';
diff --git a/test/nice.test.ts b/test/nice.test.ts
index f2999be2..b15f25e9 100644
--- a/test/nice.test.ts
+++ b/test/nice.test.ts
@@ -1,4 +1,4 @@
-import assert from 'node:assert/strict';
+import * as assert from 'node:assert/strict';
 import { resolve } from 'node:path';
 import { test } from 'node:test';
 import { getCurrentProcessPriority, WindowsThreadPriority } from '@napi-rs/nice';
diff --git a/test/option-validation.test.ts b/test/option-validation.test.ts
index b4bcb008..771ac3a0 100644
--- a/test/option-validation.test.ts
+++ b/test/option-validation.test.ts
@@ -1,4 +1,4 @@
-import assert from 'node:assert/strict';
+import * as assert from 'node:assert/strict';
 import { test } from 'node:test';
 import Piscina from '..';
 
diff --git a/test/pool-close.test.ts b/test/pool-close.test.ts
index 123acf8a..f6785e4e 100644
--- a/test/pool-close.test.ts
+++ b/test/pool-close.test.ts
@@ -1,4 +1,4 @@
-import assert from 'node:assert/strict';
+import * as assert from 'node:assert/strict';
 import { once } from 'node:events';
 import { resolve } from 'node:path';
 import { describe, it, test } from 'node:test';
diff --git a/test/pool-destroy.test.ts b/test/pool-destroy.test.ts
index 0bf7c902..d8b2e935 100644
--- a/test/pool-destroy.test.ts
+++ b/test/pool-destroy.test.ts
@@ -1,4 +1,4 @@
-import assert from 'node:assert/strict';
+import * as assert from 'node:assert/strict';
 import { test } from 'node:test';
 import { resolve } from 'node:path';
 import Piscina from '..';
diff --git a/test/pool.test.ts b/test/pool.test.ts
index c0718022..f17e275e 100644
--- a/test/pool.test.ts
+++ b/test/pool.test.ts
@@ -1,4 +1,4 @@
-import assert from 'node:assert/strict';
+import * as assert from 'node:assert/strict';
 import { resolve } from 'node:path';
 import { test } from 'node:test';
 import { once } from 'node:events';
diff --git a/test/post-task.test.ts b/test/post-task.test.ts
index aa1bdd19..969f011e 100644
--- a/test/post-task.test.ts
+++ b/test/post-task.test.ts
@@ -1,4 +1,4 @@
-import assert from 'node:assert';
+import * as assert from 'node:assert/strict';
 import { test, TestContext } from 'node:test';
 import { MessageChannel } from 'node:worker_threads';
 import { resolve } from 'node:path';
diff --git a/test/ready-message.test.ts b/test/ready-message.test.ts
index c41c323a..5c886ba9 100644
--- a/test/ready-message.test.ts
+++ b/test/ready-message.test.ts
@@ -1,4 +1,4 @@
-import assert from 'node:assert/strict';
+import * as assert from 'node:assert/strict';
 import { test } from 'node:test';
 import { resolve } from 'node:path';
 import { once } from 'node:events';
diff --git a/test/simple-test.test.ts b/test/simple-test.test.ts
index f7c6b2ea..a40c5f52 100644
--- a/test/simple-test.test.ts
+++ b/test/simple-test.test.ts
@@ -1,4 +1,4 @@
-import assert from 'node:assert';
+import * as assert from 'node:assert/strict';
 import { test } from 'node:test';
 import { pathToFileURL } from 'node:url';
 import { resolve } from 'node:path';
@@ -233,7 +233,7 @@ test('named tasks work', async () => {
   assert.strictEqual(await worker.run({}), 'a');
 });
 
-test('named tasks work', async () => {
+test('named tasks work (2)', async () => {
   const worker = new Piscina({
     filename: resolve(__dirname, 'fixtures/multiple.js'),
     name: 'b'
@@ -243,3 +243,12 @@ test('named tasks work', async () => {
   assert.strictEqual(await worker.run({}, { name: 'b' }), 'b');
   assert.strictEqual(await worker.run({}), 'b');
 });
+
+test('cjs#default named export works (#1012)', async () => {
+  const worker = new Piscina({
+    filename: resolve(__dirname, 'fixtures/cjs-default.js'),
+    name: 'default'
+  });
+
+  assert.strictEqual(await worker.run({}), 42);
+});
diff --git a/test/task-queue.test.ts b/test/task-queue.test.ts
index 11d5a6d6..01f922d0 100644
--- a/test/task-queue.test.ts
+++ b/test/task-queue.test.ts
@@ -1,4 +1,4 @@
-import assert from 'node:assert/strict';
+import * as assert from 'node:assert/strict';
 import { test } from 'node:test';
 import { resolve } from 'node:path';
 import Piscina, { PiscinaTask, TaskQueue } from '..';
diff --git a/test/test-is-buffer-transferred.test.ts b/test/test-is-buffer-transferred.test.ts
index aa2617f5..b6c272ef 100644
--- a/test/test-is-buffer-transferred.test.ts
+++ b/test/test-is-buffer-transferred.test.ts
@@ -1,4 +1,4 @@
-import assert from 'node:assert/strict';
+import * as assert from 'node:assert/strict';
 import { test } from 'node:test';
 import { resolve } from 'node:path';
 import Piscina from '..';
diff --git a/test/test-resourcelimits.test.ts b/test/test-resourcelimits.test.ts
index 02b5a0ed..33289e71 100644
--- a/test/test-resourcelimits.test.ts
+++ b/test/test-resourcelimits.test.ts
@@ -1,4 +1,4 @@
-import assert from 'node:assert/strict';
+import * as assert from 'node:assert/strict';
 import { test } from 'node:test';
 import { resolve } from 'node:path';
 import Piscina from '..';
diff --git a/test/test-uncaught-exception-from-handler.test.ts b/test/test-uncaught-exception-from-handler.test.ts
index 2fd392d9..2a8438e9 100644
--- a/test/test-uncaught-exception-from-handler.test.ts
+++ b/test/test-uncaught-exception-from-handler.test.ts
@@ -1,4 +1,4 @@
-import assert from 'node:assert/strict';
+import * as assert from 'node:assert/strict';
 import { test } from 'node:test';
 import { resolve } from 'node:path';
 import { once } from 'node:events';
diff --git a/test/thread-count.test.ts b/test/thread-count.test.ts
index ef180cac..faaf5b79 100644
--- a/test/thread-count.test.ts
+++ b/test/thread-count.test.ts
@@ -1,4 +1,4 @@
-import assert from 'node:assert/strict';
+import * as assert from 'node:assert/strict';
 import { test } from 'node:test';
 import { resolve } from 'node:path';
 import { cpus } from 'node:os';
diff --git a/test/workers.test.ts b/test/workers.test.ts
index b0b1f47f..0de37882 100644
--- a/test/workers.test.ts
+++ b/test/workers.test.ts
@@ -1,4 +1,4 @@
-import assert from 'node:assert';
+import * as assert from 'node:assert/strict';
 import { test } from 'node:test';
 import { resolve } from 'node:path';
 import Piscina from '../dist';
diff --git a/tsconfig.json b/tsconfig.json
index 1cb3ed5f..1a056eaa 100644
--- a/tsconfig.json
+++ b/tsconfig.json
@@ -15,7 +15,6 @@
     "noUnusedParameters": true,
     "noImplicitReturns": true,
     "noFallthroughCasesInSwitch": true,
-    "esModuleInterop": true,
 
     "resolveJsonModule": true,                /* Include modules imported with '.json' extension */
     "forceConsistentCasingInFileNames": true  /* Disallow inconsistently-cased references to the same file. */