diff --git a/packages/backend-test-utils/src/filesystem/MockDirectory.test.ts b/packages/backend-test-utils/src/filesystem/MockDirectory.test.ts
index 9e3efdaec0..8040d03f44 100644
--- a/packages/backend-test-utils/src/filesystem/MockDirectory.test.ts
+++ b/packages/backend-test-utils/src/filesystem/MockDirectory.test.ts
@@ -91,7 +91,7 @@ describe('createMockDirectory', () => {
 
     mockDir.addContent({
       'b.txt': 'b',
-      b: {
+      [mockDir.resolve('b')]: {
         'c.txt': 'c',
       },
     });
diff --git a/packages/backend-test-utils/src/filesystem/MockDirectory.ts b/packages/backend-test-utils/src/filesystem/MockDirectory.ts
index 20345e4ff9..61eb4fce24 100644
--- a/packages/backend-test-utils/src/filesystem/MockDirectory.ts
+++ b/packages/backend-test-utils/src/filesystem/MockDirectory.ts
@@ -279,19 +279,18 @@ class MockDirectoryImpl {
     const entries: MockEntry[] = [];
 
     function traverse(node: MockDirectoryContent[string], path: string) {
-      const trimmedPath = path.startsWith('/') ? path.slice(1) : path; // trim leading slash
       if (typeof node === 'string') {
         entries.push({
           type: 'file',
-          path: trimmedPath,
+          path,
           content: Buffer.from(node, 'utf8'),
         });
       } else if (node instanceof Buffer) {
-        entries.push({ type: 'file', path: trimmedPath, content: node });
+        entries.push({ type: 'file', path, content: node });
       } else {
-        entries.push({ type: 'dir', path: trimmedPath });
+        entries.push({ type: 'dir', path });
         for (const [name, child] of Object.entries(node)) {
-          traverse(child, `${trimmedPath}/${name}`);
+          traverse(child, path ? `${path}/${name}` : name);
         }
       }
     }