niksi: skills CLI for coding agents

niksi installs, updates, and links community skills into your coding agent. add and update scan every file before writing it and record what you installed in niksi-lock.json. install verifies that record, so your team runs the same reviewed skills.

The command is nik. The name is Finnish for a trick or knack.

Features

• Pick what you install: nik add owner/repo lists the skills in a repository and lets you choose.
• One install, every agent: Claude Code, Codex, Cursor, Gemini CLI, GitHub Copilot, OpenCode, Windsurf, Amp, Kiro, Cline, Qwen Code, and every other agent that reads .agents/skills. Each skill is stored once and symlinked into every skills directory.
• Reviewed updates: nik update compares each installed skill with its source and shows the diff before it changes anything.
• Dependencies: skills that depend on other skills from the same source are detected, and nik add offers to add them too.
• Security scan: add and update scan every file before it is written. A critical finding stops the install until you approve it. See Security scan.

Install

Homebrew, on macOS or Linux:

brew install osrim/tap/niksi

Or download the binary for your platform from the latest release and put it on your PATH. niksi needs git. For CI, see Commands.

Quickstart

nik add mattpocock/skills   # pick skills, review them, write niksi-lock.json
nik install                 # restore every skill in niksi-lock.json on a fresh checkout
nik update                  # check upstream and review what changed

Commit niksi-lock.json. nik install checks each skill against the integrity recorded in niksi-lock.json before writing it, so teammates get the files you approved.

Docs

• Commands: every command, flag, and exit code, plus non-interactive use.
• Configuration: scope, agents, paths, environment variables, and the lockfile.
• Security scan: what the scan catches and what it cannot.

Contributing

See CONTRIBUTING.md.

License

MIT