I built a GitHub star monitor in a single YAML file — zero dependencies, zero config

#github #opensource #actions #automation

GitHub doesn't notify you when someone stars your repo. Or unstars it. You either refresh your profile page like a maniac, or you just... never find out.

Tools like star-history.com let you look up trends, but you have to visit the site every time. GitHub Apps like Star Notifier automate it, but now a third-party service is handling your tokens. Self-hosted solutions like github-star-notifier need a server running somewhere.

I wanted something automatic that requires zero infrastructure. So I built it using nothing but GitHub Actions.

What it does

GitHub Star Checker monitors star counts across all your public repositories and notifies you when stars change — gains or losses.

Runs every hour by default (configurable from the GitHub UI)
Sends alerts via GitHub Issues or Gmail
Generates weekly and monthly reports
All logic lives in a single workflow file

No server, no database, no dependencies — just one YAML file and GitHub's free compute.

How it works

A cron job triggers every hour on GitHub Actions
Fetches star counts for all your public, non-fork repos via the GitHub API
Compares with the previous snapshot stored in stars.json
If anything changed → sends a notification
Commits the updated data back to the repo

The workflow updates itself — including the schedule and notification settings — so you configure everything from the GitHub UI. No code editing needed.

Since it runs in its own forked repo, your existing repositories stay completely untouched.

What the notifications look like

GitHub Issue alert

Email alert

Weekly report

Setup in 60 seconds

Fork the repo
Enable workflows in the Actions tab
Add your Personal Access Token (repo + workflow scopes) as STAR_MONITOR_TOKEN in Settings > Secrets
Run the workflow — done.

The first run records your current star counts. From the second run onward, you'll get notified about any changes.

That's it. No YAML to write, no config files to edit, no CLI to install.

Why not just use a GitHub App?

Fair question. Apps like Star Notifier are convenient — install and go. But:

They're third-party services processing your GitHub data
You can't customize the logic or notification format
If the service goes down or gets discontinued, you lose it

This project is entirely yours. It's a fork in your account, running on GitHub's own infrastructure. You can read every line of code, modify anything, and it'll keep running as long as GitHub Actions exists.

Interesting technical bits

Self-modifying YAML: When you change settings via workflow_dispatch, the workflow uses sed to update its own cron schedule and env variables, then commits the change. Future runs pick up the new settings automatically.
Zero-conflict git strategy: The workflow stashes local changes, rebases on remote, then pops — handling concurrent scheduled runs gracefully.
32-day history retention: Daily snapshots are stored in stars-history.json for weekly/monthly reports, with automatic pruning.

Limitations

Being honest about the trade-offs:

Not real-time: GitHub Actions cron can delay 5–30 minutes. This is periodic monitoring, not instant webhook-based alerts.
Notification channels: Currently supports GitHub Issues and Gmail. No Slack/Discord/Telegram yet (PRs welcome!).
Commit history: The workflow commits stars.json updates to the forked repo. This is by design (persistence without external storage), but your fork's commit log will grow over time.
API usage: Each run makes one paginated API call. Even with 100+ repos, it stays well within GitHub's rate limits.