# tz-guard

> tz-guard is a CLI and GitHub Action that statically scans SQL schema, migrations, and application code (TypeScript, JavaScript, Python) for timezone and DST bugs: naive TIMESTAMP columns that should be TIMESTAMPTZ, datetime.utcnow()/datetime.now() without tzinfo, new Date('YYYY-MM-DD') UTC-midnight traps, DST-unsafe millisecond/interval date math, and host-timezone-dependent calls. Each finding includes a plain-English production-risk explanation and a concrete fix.

## Key facts
- Install/run: `npx tz-guard` (Node >= 18). No install or signup required for public repos.
- Detection is deterministic and offline (a curated rule set), not an LLM — fast, free, reproducible, CI-safe.
- Output formats: pretty terminal, JSON, and SARIF 2.1.0 for GitHub code scanning.
- CI gating: `--fail-on error|warning|info` exits non-zero so timezone bugs block merges.
- Optional `--explain` flag enriches findings via a swappable LLM gateway (bring your own key on free tier).

## Pricing
- Free: unlimited public repos + 1 private repo, report-only CI.
- Pro: $19/month (₹1,599) per team — unlimited private repos, enforced CI gating on private repos, hosted LLM explanations.

## Links
- Site: https://tzguard.aiskillhub.info
- Pricing: https://tzguard.aiskillhub.info/pricing