Originally published on NextFuture On April 15, 2026, Cal.com announced it was going closed source . Six days later, a fork called Cal.diy hit 258 points on Hacker News. If you self-host scheduling, sell to technical buyers who hate Calendly, or run a one-person SaaS where every $20/month matters, this changes your tooling math. I've spent the last week wiring up seven scheduling tools as the booking link on a real solo SaaS. This guide ranks them for solo founders, indie makers, and technical PMs who want a Cal.com alternative that fits a 2026 workflow — including AI-driven scheduling, embedded booking widgets, and pricing that survives churn. TL;DR: The 2026 winners by use case Five quick verdicts so you can pick a Cal.com alternative without reading the rest: Use casePickStarts atWhy Open-source self-host**Cal.diy**$0 (self-host)Community fork of the last AGPL-licensed Cal.com release. Replace Cal.com fast, no migration**Calendly**$10/moMost ecosystem coverage, AI Co-Pilot for prep notes.…