---
title: Fumadocs MDX 15
description: Bump minimum Fumadocs version.
author: Fuma Nama
date: 2026-05-07
---

## Overview

This is a boring major release mainly to reduce package size. Breaking changes:

- `fumadocs-core` must be `16.7.0` or above.
- `next.config` must be ESM.

For Next.js users, if you encounter any error when upgrading, it could be due to ESM compatibility issues, you might be accidentally using CommonJS in `next.config`.
Consider to rename your config to `next.config.mjs` or `next.config.mts`.

If you prefer to use ESM in your entire project, set this in your `package.json`:

```json title="package.json"
{
  "name": "my-app",
  // [!code ++]
  "type": "module"
}
```

For other unexpected breakages, please open a bug report on our GitHub repository.
