OpenCATS

Established open-source ATS with PHP/MySQL stack

UpdatedMay 1, 2026

Free Self-hosted

OpenCATS is one of the most established open-source applicant tracking systems. It runs on a PHP/LAMP stack (PHP, Apache/Nginx, MySQL) and can be self-hosted. The project has an active community but the architecture is dated compared to modern ATS platforms. Free to use under an open-source license.

Key features

Candidate database
Job posting management
Pipeline tracking
Resume parsing
Email integration
Self-hosted — full data control

Notable integrations

EmailResume parsers

In-depth guides

Alternatives

10 Best OpenCATS Alternatives for 2026

Compare the best OpenCATS alternatives for modern ATS workflows, self-hosting, data ownership, pricing, and small-team recruiting.

Compare with alternatives

Reqcore

The ATS for teams with too many applicants — AI sorts every one and puts the best first

Recruitee

Collaborative ATS for fast-growing teams