diff --git a/README.md b/README.md
index 0023137..9a78ae5 100644
--- a/README.md
+++ b/README.md
@@ -4,6 +4,14 @@ A zero-dependency AT Protocol Personal Data Server written in JavaScript, runnin
 
 > ⚠️ **Work in progress** - This is experimental. You probably shouldn't use this yet.
 
+## Prerequisites
+
+- Node.js 18+
+- [shfmt](https://github.com/mvdan/sh) (optional, for `npm run format`)
+  ```bash
+  brew install shfmt
+  ```
+
 ## Quick Start
 
 ```bash