Best use case
nix-justfile is best used when you need a repeatable AI agent workflow instead of a one-off prompt.
Conventions for writing justfile recipes in Nix-based projects.
Teams using nix-justfile should expect a more consistent output, faster repeated execution, less prompt rewriting.
When to use this skill
- You want a reusable workflow that can be run more than once with consistent structure.
When not to use this skill
- You only need a quick one-off answer and do not need a reusable workflow.
- You cannot install or maintain the underlying files, dependencies, or repository context.
Installation
Claude Code / Cursor / Codex
Manual Installation
- Download SKILL.md from GitHub
- Place it in
.claude/skills/nix-justfile/SKILL.mdinside your project - Restart your AI agent — it will auto-discover the skill
How nix-justfile Compares
| Feature / Agent | nix-justfile | Standard Approach |
|---|---|---|
| Platform Support | Not specified | Limited / Varies |
| Context Awareness | High | Baseline |
| Installation Complexity | Unknown | N/A |
Frequently Asked Questions
What does this skill do?
Conventions for writing justfile recipes in Nix-based projects.
Where can I find the source code?
You can find the source code on GitHub using the link provided at the top of the page.
SKILL.md Source
# Justfile in Nix projects
## Doc comments
Every recipe must have a doc comment (`#` line above the recipe name).
## Devshell detection
Use a `nix_shell` variable to auto-detect whether we're inside `nix develop`:
```just
nix_shell := if env('IN_NIX_SHELL', '') != '' { '' } else { 'nix develop -c' }
```
Prefix commands that need devshell tools (node, trunk, cargo-watch, etc.) with `{{nix_shell}}`. Recipes that invoke `nix` directly (build, run, flake commands) don't need it.
## Legibility
Long chained commands should use multiline `\` continuations.Related Skills
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