diff --git a/README.md b/README.md
index 39b09ac..4741215 100644
--- a/README.md
+++ b/README.md
@@ -11,11 +11,19 @@ A shape editor desktop application built with Java Swing. Supports rectangles, c
 
 ### With Nix (recommended)
 
+If you have [direnv](https://direnv.net/) installed, the environment activates automatically:
+
+```sh
+direnv allow   # one-time, then auto-activates on cd
+```
+
+Otherwise, enter the dev shell manually:
+
 ```sh
 nix develop
 ```
 
-This drops you into a shell with JDK 17 and Maven 3.9.x preconfigured. No other setup needed.
+Both provide JDK 17 and Maven 3.9.x preconfigured. No other setup needed.
 
 ### Without Nix