Fingerprint Ci Gate

Fingerprint regressions usually surface weeks later as a spike in rejected traffic, so this skill moves that check into CI. It wraps liarjs to save a baseline scan as JSON, diffs each later run against it, and fails the job if the consistency score drops below a floor you set. The examples cover GitHub Actions and GitLab CI, and the notes are worth reading: pin the liarjs version, take the baseline in the same headless or headed mode the job uses, and avoid a hard floor on datacenter runners, where the timezone check will always trip. The diff mode is the more practical choice there, since it reports only checks whose status moved. Browser sandboxing stays on, so a container that fails to start needs an image fix, not a flag.

skills.sh installs: 119K
GitHub stars: 5
last updated: Oct 26, 2026

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Install

$ npx -y skills add liarjsdev/liarjs-skills --skill fingerprint-ci-gate --agent claude-code

Installs into .claude/skills of the current project.

Files

Fail the build, not the ban rate

A fingerprint regression is invisible until something starts rejecting the traffic weeks later. liarjs turns it into a diff in a pull request: scan, save the JSON, compare the next run against the saved baseline.

Node 22 or newer, a Chromium in the image, zero runtime dependencies.

Runner note: give the container enough shared memory (--shm-size=1g on Docker, or a /dev/shm mount) and the capabilities Chrome's own sandbox needs. Leave the browser sandbox enabled; a scan that will not start is an image problem to fix in the image.

The two mechanisms

Absolute floor. Exits 1 when the score is below the number given, so the job fails:

npx liarjs@0.3 --headless --min-score 60

Baseline diff. Prints only the checks whose status moved between two saved scans:

npx liarjs@0.3 --json scan.json                # write the current result
npx liarjs@0.3 diff baseline.json scan.json    # what changed since the known-good run

SKILL.md on GitHub