diff --git a/justfile b/justfile
index 9b7c306..523ab23 100644
--- a/justfile
+++ b/justfile
@@ -290,9 +290,14 @@ rebase-commits commit=`cd "$invokedir"; just _a_commit`:
 
 # === speed worktrees ===
 
-@bump +$packages=`just _some_packages`:
-    cd "$(just _new_worktree bump "$(printf "%s\n" $packages | head -n1 | rev | cut -d. -f1 | rev)")"; \
-    just _bump $packages; \
+bump *packages:
+    #!/usr/bin/env -S bash -euo pipefail -x
+    declare -a packages=("$@")
+    [[ -n "${packages[*]}" ]] || packages=($(just _some_packages))
+    worktree=$(just _new_worktree bump "$(printf "%s\n" "${packages[0]}" | rev | cut -d. -f1 | rev)")
+    [[ -n "worktree" ]]
+    cd "$worktree"
+    just _bump "${packages[@]}"
     NIXPKGS_ALLOW_UNFREE=1 "$SHELL"
 
 [no-cd]