diff --git a/CONTRIBUTING.md b/CONTRIBUTING.md
index 8898a7c1fa..70e7cd7f95 100644
--- a/CONTRIBUTING.md
+++ b/CONTRIBUTING.md
@@ -70,7 +70,7 @@ follow the conventions of [Keep A CHANGELOG][kacl].
 
 ## Testing
 
-nix has a test suite that you can run with `cargo test`. Ideally, we'd like pull
+nix has a test suite that you can run with `cargo test --all-features`. Ideally, we'd like pull
 requests to include tests where they make sense. For example, when fixing a bug,
 add a test that would have failed without the fix.