diff --git a/.envrc b/.envrc
index 7ee2b88b4..c57ee1c4f 100644
--- a/.envrc
+++ b/.envrc
@@ -1,5 +1,6 @@
 # If we are a computer with nix-shell available, then use that to setup
 # the build environment with exactly what we need.
 if has nix; then
+  watch_file nix/{devShell,package,wraptest}.nix
   use flake
 fi