diff --git a/nix/shell.nix b/nix/shell.nix
index d672b69..c9d2e74 100644
--- a/nix/shell.nix
+++ b/nix/shell.nix
@@ -17,7 +17,7 @@ mkShell {
     cargo
 
     # Tools
-    rustfmt
+    (rustfmt.override {asNightly = true;})
     clippy
     cargo
     taplo