---
name: nix-shell-tooling
description: "Any nixpkgs tool can be run ad hoc via nix run / nix shell — a missing command is never a dead end during development"
metadata:
  node_type: memory
  type: feedback
  originSessionId: dfb56b58-518b-4daf-b531-7119bb4a9534
---

Any tool in nixpkgs can be run without installing it into the environment. If a
command is missing during development, pull it from nixpkgs on the fly instead
of working around its absence or reporting the tool as unavailable.

**Why:** Lyra runs NixOS; the ambient PATH is deliberately minimal, but the full
nixpkgs set is always one command away. "command not found" is not a blocker.

**How to apply:**

- One-off run: `nix run nixpkgs#<pkg> -- <args>` (e.g. `nix run nixpkgs#jq -- .`).
- Tools on PATH for a session: `nix shell nixpkgs#<pkg> [nixpkgs#<pkg2> ...]`,
  then run commands normally.
- Legacy form also works: `nix-shell -p <pkg> --run '<cmd>'`.
- Prefer this over hand-rolling a substitute for a tool that exists in nixpkgs.
