Alf.io vs Cal.com
| Tagline | Open-source ticket reservation platform for events of any size | Scheduling infrastructure for everyone, the open-source Calendly alternative |
| Category | Scheduling & Booking | Scheduling & Booking |
| Replaces | Calendly, Acuity Scheduling | Calendly, Acuity Scheduling |
| GitHub stars | 1.6k | 46k |
| Language | Java | TypeScript |
| License | GPL-3.0 | AGPL-3.0 |
| Self-host difficulty | 4/5 Involved | 3/5 Moderate |
| Deploy options | Docker Docker Compose Manual | One-Click Docker Docker Compose Manual |
| Managed hosting | ||
| Last updated | 4 days ago | 2 days ago |
| View repo | View repo |
Where each falls short
The honest trade-offs — what you give up with each, versus the proprietary tools they replace.
Alf.io
- No built-in recurring appointment booking (1:1 scheduling like Calendly)
- Mobile app for attendees is not provided; check-in relies on a separate web view
- Analytics and post-event reporting are basic compared to Eventbrite or Cvent
- Initial Java/PostgreSQL setup is heavier than typical SaaS onboarding
Cal.com
- Some enterprise features (e.g. SAML SSO, advanced admin/insights, certain platform features) are gated behind a commercial/EE license even when self-hosting.
- Self-hosting requires PostgreSQL plus configuring numerous environment variables and OAuth credentials for calendar integrations.
- The core code is AGPL-3.0, which imposes copyleft obligations on modified network deployments.
- Upgrades between major versions occasionally require manual database migration work.
Bottom line
Choose Cal.com if you want the lower-effort setup; choose Cal.com for the larger community and ecosystem. Cal.com has seen more recent development. Open each guide below for deploy steps and the full feature gap.
Cal.com
Scheduling infrastructure for everyone, the open-source Calendly alternative