diff --git a/tvix/shell.nix b/tvix/shell.nix
index 9d091ae5f..3af24b1f9 100644
--- a/tvix/shell.nix
+++ b/tvix/shell.nix
@@ -18,6 +18,7 @@ pkgs.mkShell {
     pkgs.buf-language-server
     pkgs.cargo
     pkgs.cargo-machete
+    pkgs.cargo-expand
     pkgs.clippy
     pkgs.evans
     pkgs.fuse