diff --git a/test/fixtures/test-package/esm-export.js b/test/fixtures/test-package/esm-export.js
new file mode 100644
index 000000000..4da61e98d
--- /dev/null
+++ b/test/fixtures/test-package/esm-export.js
@@ -0,0 +1,7 @@
+import { PushActionPlugin } from '@finos/git-proxy/plugin';
+
+// test default export (ESM syntax)
+export default new PushActionPlugin(async (req, action) => {
+  console.log('Dummy plugin: ', action);
+  return action;
+});
diff --git a/test/fixtures/test-package/esm-multiple-export.js b/test/fixtures/test-package/esm-multiple-export.js
new file mode 100644
index 000000000..fb9c290bc
--- /dev/null
+++ b/test/fixtures/test-package/esm-multiple-export.js
@@ -0,0 +1,18 @@
+import { PushActionPlugin, PullActionPlugin } from '@finos/git-proxy/plugin';
+
+// test multiple exports (ESM syntax)
+export default {
+  foo: new PushActionPlugin(async (req, action) => {
+    console.log('PushActionPlugin: ', action);
+    return action;
+  }),
+  bar: new PullActionPlugin(async (req, action) => {
+    console.log('PullActionPlugin: ', action);
+    return action;
+  }),
+  baz: {
+    exec: async (req, action) => {
+      console.log('not a real plugin object');
+    },
+  },
+};
diff --git a/test/fixtures/test-package/esm-subclass.js b/test/fixtures/test-package/esm-subclass.js
new file mode 100644
index 000000000..164419d01
--- /dev/null
+++ b/test/fixtures/test-package/esm-subclass.js
@@ -0,0 +1,14 @@
+import { PushActionPlugin } from '@finos/git-proxy/plugin';
+
+class DummyPlugin extends PushActionPlugin {
+  constructor(exec) {
+    super();
+    this.exec = exec;
+  }
+}
+
+// test default export (ESM syntax)
+export default new DummyPlugin(async (req, action) => {
+  console.log('Dummy plugin: ', action);
+  return action;
+});
diff --git a/test/fixtures/test-package/multiple-export.js b/test/fixtures/test-package/multiple-export.js
index 9a6a5544a..672ffde28 100644
--- a/test/fixtures/test-package/multiple-export.js
+++ b/test/fixtures/test-package/multiple-export.js
@@ -9,4 +9,9 @@ module.exports = {
     console.log('PullActionPlugin: ', action);
     return action;
   }),
+  baz: {
+    exec: async (req, action) => {
+      console.log('not a real plugin object');
+    },
+  },
 };
diff --git a/test/plugin/plugin.test.js b/test/plugin/plugin.test.js
index c26929136..bb1acbdf0 100644
--- a/test/plugin/plugin.test.js
+++ b/test/plugin/plugin.test.js
@@ -2,12 +2,7 @@ import chai from 'chai';
 import { spawnSync } from 'child_process';
 import { rmSync } from 'fs';
 import { join } from 'path';
-import {
-  isCompatiblePlugin,
-  PullActionPlugin,
-  PushActionPlugin,
-  PluginLoader,
-} from '../../src/plugin.ts';
+import { isCompatiblePlugin, PushActionPlugin, PluginLoader } from '../../src/plugin.ts';
 
 chai.should();
 
@@ -22,35 +17,73 @@ describe('loading plugins from packages', function () {
     spawnSync('npm', ['install'], { cwd: testPackagePath, timeout: 5000 });
   });
 
-  it('should load plugins that are the default export (module.exports = pluginObj)', async function () {
-    const loader = new PluginLoader([join(testPackagePath, 'default-export.js')]);
-    await loader.load();
-    expect(loader.pushPlugins.length).to.equal(1);
-    expect(loader.pushPlugins.every((p) => isCompatiblePlugin(p))).to.be.true;
-    expect(loader.pushPlugins.every((p) => isCompatiblePlugin(p, 'isGitProxyPushActionPlugin'))).to
-      .be.true;
-  }).timeout(10000);
+  describe('CommonJS syntax', () => {
+    it('should load plugins that are the default export (module.exports = pluginObj)', async function () {
+      const loader = new PluginLoader([join(testPackagePath, 'default-export.js')]);
+      await loader.load();
+      expect(loader.pushPlugins.length).to.equal(1);
+      expect(loader.pushPlugins.every((p) => isCompatiblePlugin(p))).to.be.true;
+      expect(loader.pushPlugins.every((p) => isCompatiblePlugin(p, 'isGitProxyPushActionPlugin')))
+        .to.be.true;
+    }).timeout(10000);
 
-  it('should load multiple plugins from a module that match the plugin class (module.exports = { pluginFoo, pluginBar })', async function () {
-    const loader = new PluginLoader([join(testPackagePath, 'multiple-export.js')]);
-    await loader.load();
-    expect(loader.pushPlugins.length).to.equal(1);
-    expect(loader.pullPlugins.length).to.equal(1);
-    expect(loader.pushPlugins.every((p) => isCompatiblePlugin(p))).to.be.true;
-    expect(loader.pushPlugins.every((p) => isCompatiblePlugin(p, 'isGitProxyPushActionPlugin'))).to
-      .be.true;
-    expect(loader.pullPlugins.every((p) => isCompatiblePlugin(p, 'isGitProxyPullActionPlugin'))).to
-      .be.true;
-  }).timeout(10000);
+    it('should load multiple plugins from a module that match the plugin class (module.exports = { pluginFoo, pluginBar })', async function () {
+      const loader = new PluginLoader([join(testPackagePath, 'multiple-export.js')]);
+      await loader.load();
 
-  it('should load plugins that are subclassed from plugin classes', async function () {
-    const loader = new PluginLoader([join(testPackagePath, 'subclass.js')]);
-    await loader.load();
-    expect(loader.pushPlugins.length).to.equal(1);
-    expect(loader.pushPlugins.every((p) => isCompatiblePlugin(p))).to.be.true;
-    expect(loader.pushPlugins.every((p) => isCompatiblePlugin(p, 'isGitProxyPushActionPlugin'))).to
-      .be.true;
-  }).timeout(10000);
+      // Should load the foo and bar plugins, but not the baz object which isn't a plugin
+      expect(loader.pushPlugins.length).to.equal(1);
+      expect(loader.pullPlugins.length).to.equal(1);
+      expect(loader.pushPlugins.every((p) => isCompatiblePlugin(p))).to.be.true;
+      expect(loader.pushPlugins.every((p) => isCompatiblePlugin(p, 'isGitProxyPushActionPlugin')))
+        .to.be.true;
+      expect(loader.pullPlugins.every((p) => isCompatiblePlugin(p, 'isGitProxyPullActionPlugin')))
+        .to.be.true;
+    }).timeout(10000);
+
+    it('should load plugins that are subclassed from plugin classes', async function () {
+      const loader = new PluginLoader([join(testPackagePath, 'subclass.js')]);
+      await loader.load();
+      expect(loader.pushPlugins.length).to.equal(1);
+      expect(loader.pushPlugins.every((p) => isCompatiblePlugin(p))).to.be.true;
+      expect(loader.pushPlugins.every((p) => isCompatiblePlugin(p, 'isGitProxyPushActionPlugin')))
+        .to.be.true;
+    }).timeout(10000);
+  });
+
+  describe('ESM syntax', () => {
+    it('should load plugins that are the default export (exports default pluginObj)', async function () {
+      const loader = new PluginLoader([join(testPackagePath, 'esm-export.js')]);
+      await loader.load();
+      expect(loader.pushPlugins.length).to.equal(1);
+      expect(loader.pushPlugins.every((p) => isCompatiblePlugin(p))).to.be.true;
+      expect(loader.pushPlugins.every((p) => isCompatiblePlugin(p, 'isGitProxyPushActionPlugin')))
+        .to.be.true;
+    }).timeout(10000);
+
+    it('should load multiple plugins from a module that match the plugin class (exports default { pluginFoo, pluginBar })', async function () {
+      const loader = new PluginLoader([join(testPackagePath, 'esm-multiple-export.js')]);
+      await loader.load();
+
+      // Should load the foo and bar plugins, but not the baz object which isn't a plugin
+      expect(loader.pushPlugins.length).to.equal(1);
+      expect(loader.pullPlugins.length).to.equal(1);
+      expect(loader.pushPlugins.every((p) => isCompatiblePlugin(p))).to.be.true;
+      expect(loader.pushPlugins.every((p) => isCompatiblePlugin(p, 'isGitProxyPushActionPlugin')))
+        .to.be.true;
+      expect(loader.pullPlugins.every((p) => isCompatiblePlugin(p, 'isGitProxyPullActionPlugin')))
+        .to.be.true;
+    }).timeout(10000);
+
+    it('should load plugins that are subclassed from plugin classes (exports default class DummyPlugin extends PushActionPlugin {})', async function () {
+      const loader = new PluginLoader([join(testPackagePath, 'esm-subclass.js')]);
+      await loader.load();
+      expect(loader.pushPlugins.length).to.equal(1);
+      expect(loader.pushPlugins.every((p) => isCompatiblePlugin(p))).to.be.true;
+      expect(loader.pushPlugins.every((p) => isCompatiblePlugin(p, 'isGitProxyPushActionPlugin')))
+        .to.be.true;
+    }).timeout(10000);
+  });
 
   it('should not load plugins that are not valid modules', async function () {
     const loader = new PluginLoader([join(__dirname, './dummy.js')]);