The latest articles on DEV Community by Krasimir Popov (@kjpopov). https://dev.to/kjpopov https://media2.dev.to/dynamic/image/width=90,height=90,fit=cover,gravity=auto,format=auto/https:%2F%2Fdev-to-uploads.s3.us-east-2.amazonaws.com%2Fuploads%2Fuser%2Fprofile_image%2F4244722%2Fcbdbc02e-1576-47b0-a0b3-1d250ebfc74e.png https://dev.to/kjpopov en Krasimir Popov Sat, 14 Nov 2026 15:58:54 +0000 https://dev.to/kjpopov/testls-a-lightweight-ssltls-scanner-for-devs-and-website-owners-3lm9 https://dev.to/kjpopov/testls-a-lightweight-ssltls-scanner-for-devs-and-website-owners-3lm9 <p>Your site's TLS config is one bad handshake away from a CVE writeup.</p> <p>I built testls to catch that before it happens. It scans your domain and flags:</p> <p>Expired or near-expiry certs<br> Weak ciphers / protocols (TLS 1.0/1.1)<br> Misconfigured HSTS<br> Chain issues<br> It's a single binary, no dependencies, runs in seconds.</p> <p>testls example.com</p> <p>Built it because existing tools (testssl.sh, SSL Labs) are either overkill, web-only or shell only. I wanted something I could easy drop into CI (currently available on github actions marketplace) or run from a terminal in 5 seconds, but also something organizations can run at scale to create observability dashboards to monitor their websites certificate health over time.</p> <p>Repo: github.com/kjpopov/testls</p> <p>Easy to use in github actions:</p> <ul> <li>uses: kjpopov/<a href="mailto:testls@v0.6.0">testls@v0.6.0</a> with: args: --fail-on medium example.com </li> </ul> <p>Feedback welcome, a star helps and boosts my motivation.</p> devops opensource security showdev