diff --git a/.eslintrc.js b/.eslintrc.json
similarity index 78%
rename from .eslintrc.js
rename to .eslintrc.json
index b155f8c..478ba08 100644
--- a/.eslintrc.js
+++ b/.eslintrc.json
@@ -1,4 +1,4 @@
-module.exports = {
+{
     "env": {
         "commonjs": true,
         "es6": true,
@@ -15,5 +15,7 @@ module.exports = {
         "ecmaVersion": 2018
     },
     "rules": {
+        "import/extensions": "off",
+        "import/prefer-default-export": "off"
     }
-};
\ No newline at end of file
+}
diff --git a/.npmignore b/.npmignore
index 56a4f91..171fdd9 100644
--- a/.npmignore
+++ b/.npmignore
@@ -1,4 +1,4 @@
-.eslintrc.js
+.eslintrc.json
 test
 .cache
 .nyc_output
diff --git a/classes/caching/file_system_cache.js b/classes/caching/file_system_cache.js
index cdc616a..ccaec8a 100644
--- a/classes/caching/file_system_cache.js
+++ b/classes/caching/file_system_cache.js
@@ -1,7 +1,7 @@
-const FPersist = require('fpersist');
-const KeyTimeout = require('./key_timeout.js');
+import FPersist from 'fpersist';
+import { KeyTimeout } from './key_timeout.js';
 
-module.exports = class FileSystemCache {
+export class FileSystemCache {
   constructor(options = {}) {
     this.ttl = options.ttl;
     this.keyTimeout = new KeyTimeout();
@@ -26,4 +26,4 @@ module.exports = class FileSystemCache {
       this.keyTimeout.updateTimeout(key, this.ttl, () => this.remove(key));
     }
   }
-};
+}
diff --git a/classes/caching/key_timeout.js b/classes/caching/key_timeout.js
index 42e1367..f669b72 100644
--- a/classes/caching/key_timeout.js
+++ b/classes/caching/key_timeout.js
@@ -1,4 +1,4 @@
-module.exports = class KeyTimeout {
+export class KeyTimeout {
   constructor() {
     this.timeoutHandleForKey = {};
   }
@@ -13,4 +13,4 @@ module.exports = class KeyTimeout {
       callback();
     }, durationMs);
   }
-};
+}
diff --git a/classes/caching/memory_cache.js b/classes/caching/memory_cache.js
index d6bf0bb..1f69a85 100644
--- a/classes/caching/memory_cache.js
+++ b/classes/caching/memory_cache.js
@@ -1,6 +1,6 @@
-const KeyTimeout = require('./key_timeout.js');
+import { KeyTimeout } from './key_timeout.js';
 
-module.exports = class MemoryCache {
+export class MemoryCache {
   constructor(options = {}) {
     this.ttl = options.ttl;
     this.keyTimeout = new KeyTimeout();
@@ -23,4 +23,4 @@ module.exports = class MemoryCache {
       this.keyTimeout.updateTimeout(key, this.ttl, () => this.remove(key));
     }
   }
-};
+}
diff --git a/classes/headers.js b/classes/headers.js
index 149eb29..fbbc6b0 100644
--- a/classes/headers.js
+++ b/classes/headers.js
@@ -1,4 +1,4 @@
-class Headers {
+export class Headers {
   constructor(rawHeaders) {
     this.rawHeaders = rawHeaders;
   }
@@ -29,5 +29,3 @@ class Headers {
     return this.rawHeaders;
   }
 }
-
-module.exports = Headers;
diff --git a/classes/response.js b/classes/response.js
index f3f6653..47f123e 100644
--- a/classes/response.js
+++ b/classes/response.js
@@ -1,7 +1,7 @@
-const stream = require('stream');
-const Headers = require('./headers.js');
+import stream from 'stream';
+import { Headers } from './headers.js';
 
-class Response {
+export class Response {
   constructor(raw, ejectSelfFromCache, fromCache) {
     Object.assign(this, raw);
     this.ejectSelfFromCache = ejectSelfFromCache;
@@ -43,5 +43,3 @@ class Response {
     return this.ejectSelfFromCache();
   }
 }
-
-module.exports = Response;
diff --git a/index.js b/index.js
index 1713a73..fe6a83f 100644
--- a/index.js
+++ b/index.js
@@ -1,10 +1,9 @@
-const fetch = require('node-fetch');
-const fs = require('fs');
-const { URLSearchParams } = require('url');
-const crypto = require('crypto');
-const Response = require('./classes/response.js');
-const MemoryCache = require('./classes/caching/memory_cache.js');
-const FileSystemCache = require('./classes/caching/file_system_cache.js');
+import fetch from 'node-fetch';
+import fs from 'fs';
+import { URLSearchParams } from 'url';
+import crypto from 'crypto';
+import { Response } from './classes/response.js';
+import { MemoryCache } from './classes/caching/memory_cache.js';
 
 const CACHE_VERSION = 2;
 
@@ -112,7 +111,7 @@ function createFetchWithCache(cache) {
 
 const defaultFetch = createFetchWithCache(new MemoryCache());
 
-module.exports = defaultFetch;
-module.exports.fetchBuilder = defaultFetch;
-module.exports.MemoryCache = MemoryCache;
-module.exports.FileSystemCache = FileSystemCache;
+export default defaultFetch;
+export const fetchBuilder = defaultFetch;
+export { MemoryCache } from './classes/caching/memory_cache.js';
+export { FileSystemCache } from './classes/caching/file_system_cache.js';
diff --git a/package-lock.json b/package-lock.json
index 6d0668e..7756126 100644
--- a/package-lock.json
+++ b/package-lock.json
@@ -1,6 +1,6 @@
 {
   "name": "node-fetch-cache",
-  "version": "2.0.1",
+  "version": "2.0.3",
   "lockfileVersion": 1,
   "requires": true,
   "dependencies": {
diff --git a/package.json b/package.json
index a2f96b5..38c65ee 100644
--- a/package.json
+++ b/package.json
@@ -3,6 +3,7 @@
   "version": "2.0.3",
   "description": "node-fetch with a persistent cache.",
   "main": "index.js",
+  "type": "module",
   "scripts": {
     "test": "mocha --timeout 10000 --exit",
     "coverage": "nyc --reporter=lcov --reporter=text npm test",
@@ -38,7 +39,7 @@
   },
   "dependencies": {
     "fpersist": "^1.0.5",
-    "node-fetch": "*"
+    "node-fetch": "2.6.1"
   },
   "husky": {
     "hooks": {
diff --git a/test/tests.js b/test/tests.js
index b131f33..5a824b6 100644
--- a/test/tests.js
+++ b/test/tests.js
@@ -1,12 +1,16 @@
-const fs = require('fs');
-const FormData = require('form-data');
-const assert = require('assert');
-const rimraf = require('rimraf');
-const path = require('path');
-const { URLSearchParams } = require('url');
-const standardFetch = require('node-fetch');
-const FetchCache = require('../index.js');
-const { Agent } = require('http');
+import { dirname } from 'path';
+import { fileURLToPath } from 'url';
+import fs from 'fs';
+import FormData from 'form-data';
+import assert from 'assert';
+import rimraf from 'rimraf';
+import path from 'path';
+import { URLSearchParams } from 'url';
+import standardFetch from 'node-fetch';
+import FetchCache, { MemoryCache, FileSystemCache } from '../index.js';
+import { Agent } from 'http';
+
+const __dirname = dirname(fileURLToPath(import.meta.url));
 
 const CACHE_PATH = path.join(__dirname, '..', '.cache');
 const expectedPngBuffer = fs.readFileSync(path.join(__dirname, 'expected_png.png'));
@@ -60,9 +64,11 @@ async function dualFetch(...args) {
 
 beforeEach(async function() {
   rimraf.sync(CACHE_PATH);
-  cachedFetch = FetchCache.withCache(new FetchCache.MemoryCache());
+  cachedFetch = FetchCache.withCache(new MemoryCache());
 });
 
+let res;
+
 describe('Basic property tests', function() {
   it('Has a status property', async function() {
     let { cachedFetchResponse, standardFetchResponse } = await dualFetch(TWO_HUNDRED_URL);
@@ -253,7 +259,7 @@ describe('Cache tests', function() {
   });
 
   it('Gives different read streams different cache keys', async function() {
-    const s1 = fs.createReadStream(__filename);
+    const s1 = fs.createReadStream(path.join(__dirname, 'expected_png.png'));
     const s2 = fs.createReadStream(path.join(__dirname, '..', 'index.js'));
 
     res = await cachedFetch(TWO_HUNDRED_URL, post(s1));
@@ -264,7 +270,7 @@ describe('Cache tests', function() {
   });
 
   it('Gives the same read streams the same cache key', async function() {
-    const s1 = fs.createReadStream(__filename);
+    const s1 = fs.createReadStream(path.join(__dirname, 'expected_png.png'));
 
     res = await cachedFetch(TWO_HUNDRED_URL, post(s1));
     assert.strictEqual(res.fromCache, false);
@@ -402,7 +408,7 @@ describe('Data tests', function() {
 
 describe('Memory cache tests', function() {
   it('Supports TTL', async function() {
-    cachedFetch = FetchCache.withCache(new FetchCache.MemoryCache({ ttl: 100 }));
+    cachedFetch = FetchCache.withCache(new MemoryCache({ ttl: 100 }));
     let res = await cachedFetch(TWO_HUNDRED_URL);
     assert.strictEqual(res.fromCache, false);
     res = await cachedFetch(TWO_HUNDRED_URL);
@@ -417,7 +423,7 @@ describe('Memory cache tests', function() {
 
 describe('File system cache tests', function() {
   it('Supports TTL', async function() {
-    cachedFetch = FetchCache.withCache(new FetchCache.FileSystemCache({ ttl: 100 }));
+    cachedFetch = FetchCache.withCache(new FileSystemCache({ ttl: 100 }));
     let res = await cachedFetch(TWO_HUNDRED_URL);
     assert.strictEqual(res.fromCache, false);
     res = await cachedFetch(TWO_HUNDRED_URL);
@@ -430,7 +436,7 @@ describe('File system cache tests', function() {
   });
 
   it('Can get PNG buffer body', async function() {
-    cachedFetch = FetchCache.withCache(new FetchCache.FileSystemCache());
+    cachedFetch = FetchCache.withCache(new FileSystemCache());
     res = await cachedFetch(PNG_BODY_URL);
     body = await res.buffer();
     assert.strictEqual(expectedPngBuffer.equals(body), true);