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Debug and evaluate Nix flake expressions. An agent skill from r17x/universe.
No licenceAuto-check: notes
Install Nix Flake
$ npx skills add r17x/universe --skill nix-flake -a claude-codeProject install by default; add -g for ~/.claude/skills/.
$ gh skill install r17x/universe nix-flake --agent claude-codeProject scope by default; add --scope user for a personal install. Needs GitHub CLI 2.90.0 or later (public preview).
$ git clone --depth 1 https://github.com/r17x/universe.git skills-src && mkdir -p .claude/skills && cp -r skills-src/.claude/skills/nix/flake .claude/skills/nix-flake && rm -rf skills-srcUse ~/.claude/skills/ instead of .claude/skills for a personal install. The folder must contain SKILL.md.
Claude Code skills documentation · loads skills from .claude/skills/
Install the "nix-flake" agent skill from https://github.com/r17x/universe/tree/main/.claude/skills/nix/flake into .claude/skills/nix-flake/ in this project. Copy the whole folder (SKILL.md and every file beside it), keep the folder name "nix-flake", then confirm the skill loads.Claude Code copies the folder itself, the same result as the manual copy. Check what it changed before you commit it.
$skill-installer install https://github.com/r17x/universe/tree/main/.claude/skills/nix/flakeType this inside Codex. $skill-installer <name> installs a curated skill from openai/skills. The installer writes to $CODEX_HOME/skills (default ~/.codex/skills). Restart Codex if the skill does not show up.
$ npx skills add r17x/universe --skill nix-flake -a codexProject install goes to .agents/skills/; add -g for ~/.codex/skills/.
$ gh skill install r17x/universe nix-flake --agent codexProject scope by default (.agents/skills/); add --scope user for a personal install.
$ git clone --depth 1 https://github.com/r17x/universe.git skills-src && mkdir -p .agents/skills && cp -r skills-src/.claude/skills/nix/flake .agents/skills/nix-flake && rm -rf skills-srcUse ~/.agents/skills/ instead of .agents/skills for a personal install.
Codex skills documentation · loads skills from .agents/skills/
Install the "nix-flake" agent skill from https://github.com/r17x/universe/tree/main/.claude/skills/nix/flake into .agents/skills/nix-flake/ in this project. Copy the whole folder (SKILL.md and every file beside it), keep the folder name "nix-flake", then confirm the skill loads.Codex copies the folder itself, the same result as the manual copy. Check what it changed before you commit it.
$ npx skills add r17x/universe --skill nix-flake -a cursorProject install goes to .agents/skills/; add -g for ~/.cursor/skills/.
$ gh skill install r17x/universe nix-flake --agent cursorProject scope by default (.agents/skills/); add --scope user for a personal install.
$ git clone --depth 1 https://github.com/r17x/universe.git skills-src && mkdir -p .cursor/skills && cp -r skills-src/.claude/skills/nix/flake .cursor/skills/nix-flake && rm -rf skills-srcUse ~/.cursor/skills/ instead of .cursor/skills for a personal install.
Cursor skills documentation · loads skills from .cursor/skills/, .agents/skills/, .claude/skills/, .codex/skills/
Install the "nix-flake" agent skill from https://github.com/r17x/universe/tree/main/.claude/skills/nix/flake into .cursor/skills/nix-flake/ in this project. Copy the whole folder (SKILL.md and every file beside it), keep the folder name "nix-flake", then confirm the skill loads.Cursor copies the folder itself, the same result as the manual copy. Check what it changed before you commit it.
$ gemini skills install https://github.com/r17x/universe.git --path .claude/skills/nix/flake--scope user (default) or --scope workspace; --path is the subfolder of the repo that holds the skill; --consent skips the security confirmation prompt.
$ npx skills add r17x/universe --skill nix-flake -a gemini-cliProject install goes to .agents/skills/; add -g for ~/.gemini/skills/.
$ gh skill install r17x/universe nix-flake --agent gemini-cliProject scope by default (.agents/skills/); add --scope user for a personal install.
$ git clone --depth 1 https://github.com/r17x/universe.git skills-src && mkdir -p .gemini/skills && cp -r skills-src/.claude/skills/nix/flake .gemini/skills/nix-flake && rm -rf skills-srcUse ~/.gemini/skills/ instead of .gemini/skills for a personal install, then run /skills reload.
Gemini CLI skills documentation · loads skills from .gemini/skills/, .agents/skills/
Install the "nix-flake" agent skill from https://github.com/r17x/universe/tree/main/.claude/skills/nix/flake into .gemini/skills/nix-flake/ in this project. Copy the whole folder (SKILL.md and every file beside it), keep the folder name "nix-flake", then confirm the skill loads.Gemini CLI copies the folder itself, the same result as the manual copy. Check what it changed before you commit it.
$ gh skill install r17x/universe nix-flakeInstalls for Copilot at project scope by default; add --scope user for a personal install. Preview a skill first with gh skill preview. Needs GitHub CLI 2.90.0 or later (public preview).
$ npx skills add r17x/universe --skill nix-flake -a github-copilotProject install goes to .agents/skills/; add -g for ~/.copilot/skills/.
$ git clone --depth 1 https://github.com/r17x/universe.git skills-src && mkdir -p .github/skills && cp -r skills-src/.claude/skills/nix/flake .github/skills/nix-flake && rm -rf skills-srcUse ~/.copilot/skills/ instead of .github/skills for a personal install. Commit .github/skills so cloud agent and code review can use it.
GitHub Copilot skills documentation · loads skills from .github/skills/, .claude/skills/, .agents/skills/
Install the "nix-flake" agent skill from https://github.com/r17x/universe/tree/main/.claude/skills/nix/flake into .github/skills/nix-flake/ in this project. Copy the whole folder (SKILL.md and every file beside it), keep the folder name "nix-flake", then confirm the skill loads.GitHub Copilot copies the folder itself, the same result as the manual copy. Check what it changed before you commit it.
$ npx skills add r17x/universe --skill nix-flake -a opencodeOpenCode documents no install command of its own. Project install goes to .agents/skills/; add -g for ~/.config/opencode/skills/.
$ gh skill install r17x/universe nix-flake --agent opencodeProject scope by default (.agents/skills/); add --scope user for a personal install.
$ git clone --depth 1 https://github.com/r17x/universe.git skills-src && mkdir -p .opencode/skills && cp -r skills-src/.claude/skills/nix/flake .opencode/skills/nix-flake && rm -rf skills-srcUse ~/.config/opencode/skills/ instead of .opencode/skills for a personal install.
OpenCode skills documentation · loads skills from .opencode/skills/, .claude/skills/, .agents/skills/
Install the "nix-flake" agent skill from https://github.com/r17x/universe/tree/main/.claude/skills/nix/flake into .opencode/skills/nix-flake/ in this project. Copy the whole folder (SKILL.md and every file beside it), keep the folder name "nix-flake", then confirm the skill loads.OpenCode copies the folder itself, the same result as the manual copy. Check what it changed before you commit it.
Facts
- Skill name
nix-flake- GitHub stars
- 151
- Token cost
- ~613 tokens
- SKILL.md length
- 48 words
- Files
- 1
- Skills in repo
- 5
- Repo updated
- First seen
- Licence
- None found
At a glance
Debug and evaluate Nix flake expressions. An agent skill from r17x/universe.
- SKILL.md covers Flake Structure, nix eval Patterns, nix repl Deep Dive and Input Management, plus 1 more section
- Calls nix and jq
What it does
Nix Flake is an agent skill from r17x/universe. Debug and evaluate Nix flake expressions
Its SKILL.md is about 610 tokens, which your agent loads only when the skill is triggered. It is a single SKILL.md file with no bundled scripts.
The repository describes itself as: let universe speak itself ❄️ ƛ.
Example prompts
- “/nix-flake”
Requirements
- Pre-approved tools (allowed-tools): Bash, Read
What it can do on your machine
Read from SKILL.md and the folder at commit 489dbda. It shows what the files ask for, not the result of running them.
Tool permissions
Pre-approves these tools, so the agent can use them without asking each time:
BashRead
From allowed-tools in the SKILL.md frontmatter.
Runs code
Shell commands in SKILL.md call:
nixjq
From the folder's file list and the shell code blocks in SKILL.md.
Network
No URLs in SKILL.md.
From URLs in SKILL.md, links to its own repository left out.
Credentials
Names no API keys, tokens, secrets or passwords.
From names ending in _API_KEY, _TOKEN, _SECRET, _KEY or _PASSWORD in SKILL.md.
Context cost
Nix Flake loads about 613 tokens when it runs. Until then it costs about 13 tokens; SKILL.md has 48 words of instructions outside code blocks.
Estimates: characters ÷ 4, the usual rule of thumb; real counts depend on the model's tokenizer. Scripts and assets cost tokens only if the agent reads them.
Safety
Auto-check: notes
The automated check noted patterns worth knowing about, such as sudo or a known installer.
- NotePre-approves every shell command (allowed-tools: Bash)SKILL.md
allowed-tools: Bash, Read
Automated static check — not a guarantee. Review scripts before installing. It scans the text of SKILL.md for risky patterns (piping downloads into a shell, reading credential files, hidden Unicode, destructive commands); files beside SKILL.md are not scanned.
SKILL.md
Without a licence we can't republish the file, so here is its outline and opening line. It has 48 words (~613 tokens).
- name
- nix-flake
- allowed-tools
- Bash, Read
Files
Just SKILL.md in .claude/skills/nix/flake of r17x/universe.
Open the folder on GitHubat commit 489dbda
Compare with similar skills
Nix Flake next to the 5 skills that share the most tags, products or categories with it. Stars are the repository's; “used in” counts other GitHub owners with a copy.
| Skill | Stars | Used in | Tokens | Auto-check | Licence | Repo updated |
|---|---|---|---|---|---|---|
| Nix Flake this skillr17x/universe | 151 | — | ~613 | Automated safety check: Notes | None | |
| Debugasgeirtj/system_prompts_leaks | 69k | — | ~439 | Automated safety check: Pass | CC0-1.0 | |
| Openclaw Debuggingopenclaw/openclaw | 392k | — | ~1.9k | Automated safety check: Pass | MIT | |
| Debugging Executionsn8n-io/n8n | 207k | — | ~2.6k | Automated safety check: Pass | Custom licence | |
| Debugging Toolkitsickn33/agentic-awesome-skills | 47k | 1 repos | ~344 | Automated safety check: Pass | MIT | |
| Runtime Debugvercel/next.js | 143k | 1 repos | ~618 | Automated safety check: Pass | MIT |
Similar skills
Openclaw Debugging
openclaw/openclaw
Debug OpenClaw model, provider, tool-surface, code-mode, streaming, and live/Crabbox behavior by choosing the right logs, probes, and proof path before changing code, including fetching stored…
- Official
Debugging Executions
n8n-io/n8n
Debug failed or wrong-output workflow executions using executions tools.
Debugging Toolkit
sickn33/agentic-awesome-skills
A skill your agent uses when working with debugging toolkit smart debug (Alias for debugging-toolkit-smart-debug)
- Official
Runtime Debug
vercel/next.js
Debug and verification workflow for runtime-bundle and module-resolution regressions.
Hypothesis-Driven Debugging
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Runs a hypothesis-driven debugging loop for crashes, hangs and silent failures in any language, grounding every claim in runtime evidence and locking the fix with a test.
More from r17x/universe
Nix
r17x/universe
Nix flakes, nix-darwin, NixOS, and home-manager development assistance
Nix Debug
r17x/universe
Deep debugging of Nix expressions, evaluation, and derivations
Nix Module
r17x/universe
Create and structure Nix modules for darwin, NixOS, or home-manager
Nix Service
r17x/universe
Manage nix-managed launchd and systemd services. An agent skill from r17x/universe.
Questions about Nix Flake
What does Nix Flake do?
Debug and evaluate Nix flake expressions. An agent skill from r17x/universe. Nix Flake is an agent skill from r17x/universe.
How do I install Nix Flake in Claude Code?
Run `npx skills add r17x/universe --skill nix-flake -a claude-code`. Or copy the skill folder (.claude/skills/nix/flake in r17x/universe) into .claude/skills/nix-flake in your project. Claude Code loads it when a task matches its description.
How do I install Nix Flake in Codex?
Run `npx skills add r17x/universe --skill nix-flake -a codex`. Or copy the skill folder (.claude/skills/nix/flake in r17x/universe) into .agents/skills/nix-flake in your project. Codex loads it when a task matches its description.
Can I use Nix Flake in Cursor, Gemini CLI or GitHub Copilot?
Cursor, Gemini CLI, GitHub Copilot and OpenCode also load SKILL.md folders. With the skills CLI, run `npx skills add r17x/universe --skill nix-flake -a cursor` (or -a gemini-cli, github-copilot or opencode for the others). To copy it by hand, put the folder in .cursor/skills/nix-flake, .gemini/skills/nix-flake, .github/skills/nix-flake and .opencode/skills/nix-flake in your project.
What does Nix Flake need to run?
Going by SKILL.md and its folder, Nix Flake needs the command-line tools its instructions call (nix and jq). Its frontmatter pre-approves these tools: Bash, Read.
Does Nix Flake access the network?
SKILL.md contains no URLs. Any network use would come from the scripts or tools the agent runs. This is read from the text; nothing was executed.
Is Nix Flake safe to install?
Our automated static check of SKILL.md found notes only (pre-approves every shell command (allowed-tools: bash)), nothing it rates as a warning. It is not a guarantee. Review the folder before installing.
What licence does Nix Flake use?
No licence was found for Nix Flake or its repository. Without one, default copyright applies: ask the author before reusing or redistributing it.
How many tokens does Nix Flake use?
About 613 tokens (SKILL.md is roughly 2.5k characters). Agents keep only the skill's name and description in context until a task matches; then they load SKILL.md in full.
What are the alternatives to Nix Flake?
Skills that share tags, products or a category with Nix Flake: Debug (asgeirtj/system_prompts_leaks, 69k stars), Openclaw Debugging (openclaw/openclaw, 392k stars), Debugging Executions (n8n-io/n8n, 207k stars) and Debugging Toolkit (sickn33/agentic-awesome-skills, 47k stars). The comparison table on this page puts their stars, adoption, token cost, safety result and licence side by side.
Who maintains Nix Flake?
r17x (a GitHub user) maintains it in r17x/universe, which has 151 GitHub stars. The repository holds 5 skills in this directory. The repository was last updated on October 4, 2026.
Source: r17x/universe on GitHub. Facts on this page come from the repository at the commit we read; the author's words are quoted as theirs.