diff --git a/README.md b/README.md
index 2c5c1ff..1455897 100644
--- a/README.md
+++ b/README.md
@@ -226,7 +226,7 @@ If you want to try the main branch from the repository instead of a
 release version, you can run
 
 ```bash
-cargo install --git https://github.com/NLnetLabs/routinator.git --branch main
+cargo install --locked --git https://github.com/NLnetLabs/routinator.git --branch main
 ```
 
 If you want to update an installed version, you run the same command but