Cal.com is going closed source

cal.com
April 15, 2026
3 min read
65/100
Summary
Cal.com is transitioning from open source to closed source to enhance customer data protection in response to AI-driven security threats. The Cal.diy platform will remain available as an open-source option for hobbyists.
Key Takeaways
- Cal.com is transitioning from open source to closed source due to increasing security threats posed by AI.
- AI can now systematically scan open source codebases for vulnerabilities, making them more susceptible to exploitation.
- The company will continue to offer an open source version called Cal.diy for developers and hobbyists, while the production codebase will remain closed.
- Advanced AI models have demonstrated the ability to identify and exploit vulnerabilities at unprecedented speeds, highlighting the urgency of the security landscape.
Coverage & discussions
Hacker News · cal.com
Community discussions
Historical count: 5 · 5 saved in sample · Historical sample
Analysis ready
Community Sentiment
Positives
- LLMs are proving to be highly effective at identifying vulnerabilities in code, suggesting a valuable role for AI in enhancing software security practices.
- The discussion around AI's impact on open source highlights the potential for self-hosting to become more accessible, which could empower developers.
Concerns
- The shift to closed source is perceived as a business decision rather than a genuine security concern, raising questions about transparency and trust.
- There are fears that relying on closed source software for security could lead to a dangerous model of security through obscurity, which is widely criticized.
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