StackClock

Most monitoring tells you something broke. StackClock tells you what will break, and when. One timeline for every deadline in your stack: domain and SSL expiry, API keys and licenses, vendor API shutdowns (OpenAI, Stripe, GitHub...), deprecated npm/PyPI/Go packages, known vulnerabilities and end-of-life runtimes. Import a package.json or lock file and it's checked daily. Alerts by email, Slack or webhook. Never stores secrets. Free plan.