The time-management platform Cal.com is transitioning to a closed development model.

On April 14, 2026, the company announced that Cal.com is moving to closed source. On April 15, this was confirmed in the changelog v6.4: the open part of the project is being relaunched under the name Cal.diy, and the code of the commercial edition of Cal.com will no longer be published. The team emphasizes that the commercial part was not fully open source before, but source-available; now it is becoming completely closed.

The official reason given by Cal.com is the increase in security risks in the AI era. The company explicitly states that AI coding assistants and automated analysis tools have significantly simplified the search for vulnerabilities in public code, and for a service that handles schedules, customer data, and corporate processes, this has become a highly sensitive factor. According to the company's wording, the priority now is to protect customer data and managed infrastructure.

What exactly has been closed. According to the company, it is the code of the commercial edition that is being closed—the version used by Cal.com clients as a managed service. Features related to the commercial and enterprise model are being removed from the open branch. However, for self-hosting, the team promises to keep all “free features” in Cal.diy.

Cal.com is an online booking and meeting coordination platform that the project describes as “infrastructure for time”: from simple personal booking links to embedded scheduling for products, teams, marketplaces, sales, HR, healthcare, and enterprise scenarios. The service has a public API, a self-hosted option, workflow automation mechanisms, routing forms for request routing, integrations, and an app framework.

To elaborate, Cal.com developed not just a “Cal endly alternative,” but rather a planning platform:

• personal and team booking pages;
• meeting distribution among employees, including round-robin;
• lead and client routing forms;
• workflow automation for notifications and actions;
• API and OAuth for embedding scheduling in third-party products;
• self-hosted and enterprise editions for companies that prioritize control, customization, and security requirements.

What remains open. The open project features a Cal.diy MIT-licensed self-hosted option. On GitHub, it is described as a community-driven fork/platform with removed enterprise/commercial code. In a technical explanation, Cal.com states that Cal.diy retains the core scheduling engine, booking infrastructure, and app store framework., which means that the basic functionality for self-hosting remains.

Source: linux.org.ru