diff --git a/src/Module.js b/src/Module.js
index 1c65807..74f7b74 100644
--- a/src/Module.js
+++ b/src/Module.js
@@ -315,6 +315,7 @@ export default class Module {
 	toJSON () {
 		return {
 			id: this.id,
+			dependencies: this.dependencies.map( module => module.id ),
 			code: this.code,
 			originalCode: this.originalCode,
 			ast: this.astClone,
diff --git a/test/function/module-tree/_config.js b/test/function/module-tree/_config.js
new file mode 100644
index 0000000..553ab2b
--- /dev/null
+++ b/test/function/module-tree/_config.js
@@ -0,0 +1,37 @@
+const path = require( 'path' );
+const assert = require( 'assert' );
+
+module.exports = {
+	description: 'bundle.modules includes dependencies (#903)',
+	bundle ( bundle ) {
+		const modules = bundle.modules.map( module => {
+			return {
+				id: path.relative( __dirname, module.id ),
+				dependencies: module.dependencies.map( id => path.relative( __dirname, id ) )
+			};
+		});
+
+		assert.deepEqual( modules, [
+			{
+				id: path.normalize( 'nested/qux.js' ),
+				dependencies: []
+			},
+			{
+				id: path.normalize( 'nested/baz.js' ),
+				dependencies: [ path.normalize( 'nested/qux.js' ) ]
+			},
+			{
+				id: 'bar.js',
+				dependencies: [ path.normalize( 'nested/baz.js' ) ]
+			},
+			{
+				id: 'foo.js',
+				dependencies: [ 'bar.js' ]
+			},
+			{
+				id: 'main.js',
+				dependencies: [ 'foo.js', 'bar.js' ]
+			}
+		]);
+	}
+};
diff --git a/test/function/module-tree/bar.js b/test/function/module-tree/bar.js
new file mode 100644
index 0000000..76340f6
--- /dev/null
+++ b/test/function/module-tree/bar.js
@@ -0,0 +1 @@
+import './nested/baz.js';
diff --git a/test/function/module-tree/foo.js b/test/function/module-tree/foo.js
new file mode 100644
index 0000000..1df02c2
--- /dev/null
+++ b/test/function/module-tree/foo.js
@@ -0,0 +1 @@
+import './bar.js';
diff --git a/test/function/module-tree/main.js b/test/function/module-tree/main.js
new file mode 100644
index 0000000..f257022
--- /dev/null
+++ b/test/function/module-tree/main.js
@@ -0,0 +1,2 @@
+import './foo.js';
+import './bar.js';
diff --git a/test/function/module-tree/nested/baz.js b/test/function/module-tree/nested/baz.js
new file mode 100644
index 0000000..0ff2bf9
--- /dev/null
+++ b/test/function/module-tree/nested/baz.js
@@ -0,0 +1 @@
+import qux from './qux.js';
diff --git a/test/function/module-tree/nested/qux.js b/test/function/module-tree/nested/qux.js
new file mode 100644
index 0000000..6d70fec
--- /dev/null
+++ b/test/function/module-tree/nested/qux.js
@@ -0,0 +1 @@
+export default 'whatever';