diff --git a/echidna.nix b/echidna.nix
index e4f6c68..06bebd3 100644
--- a/echidna.nix
+++ b/echidna.nix
@@ -32,7 +32,9 @@ in {
     pkgs.pass
     pkgs.pipenv
     pkgs.ripgrep
+    pkgs.shellcheck
     pkgs.terraform
+    pkgs.tree
     pkgs.vagrant
     pkgs.virtualenv
     pkgs.wget