Easy!Appointments
GroupwareOpen-source web appointment scheduler
Replaces Calendly, Acuity Scheduling
Best API Groupware for self-hosting
The 10 best API groupware you can self-host, ranked by community traction.
ZenTao
GroupwareOpen-source project and team collaboration platform
Replaces Jira, Confluence
Cozy
GroupwarePersonal cloud platform with contacts and calendar
Replaces Google Workspace
EGroupware
GroupwareWeb-based groupware and team collaboration suite
Replaces Microsoft 365, Google Workspace
Group-Office
GroupwareWeb-based groupware and CRM with email and calendar
Replaces Microsoft 365, Google Workspace
Kolab Groupware
GroupwareOpen-source groupware server with mail and calendaring
Replaces Microsoft Exchange, Zimbra
Feng Office
GroupwareWeb-based collaboration and project management suite
Replaces Basecamp, Microsoft Project
Kopano Groupware Core
GroupwareOpen-source collaboration platform with Outlook support
Replaces Microsoft Exchange
Tine
GroupwareProfessional open-source groupware and CRM
Replaces Microsoft 365, Google Workspace
Cozy Contacts
GroupwareContacts management app for the Cozy personal server
Replaces Google Contacts
No apps match these filters.
At a glance
| App | Deploy effort | Difficulty | Min. RAM | License | ★ Stars |
|---|---|---|---|---|---|
| Easy!Appointments | Under-an-hour setup | Easy | 256 MB | GPL-3.0 | 4,433 |
| ZenTao | Under-an-hour setup | Medium | 1,024 MB | AGPL-3.0 | 1,699 |
| Cozy | Under-an-hour setup | Hard | 1,024 MB | AGPL-3.0 | 1,269 |
| EGroupware | Under-an-hour setup | Medium | 1,024 MB | GPL-2.0 | 298 |
| Group-Office | Under-an-hour setup | Medium | 1,024 MB | AGPL-3.0 | 282 |
| Kolab Groupware | Under-an-hour setup | Hard | 2,048 MB | AGPL-3.0 | 200 |
| Feng Office | Read-the-docs project | Medium | 512 MB | AGPL-3.0 | 108 |
| Kopano Groupware Core | Under-an-hour setup | Hard | 2,048 MB | AGPL-3.0 | 60 |
| Tine | Under-an-hour setup | Medium | 1,024 MB | AGPL-3.0 | 22 |
| Cozy Contacts | Read-the-docs project | Medium | 256 MB | AGPL-3.0 | 11 |
Quick picks
- Most adopted: Easy!Appointments (4,433 GitHub stars).
- Lightest footprint: Easy!Appointments (from 256 MB RAM, against 2,048 MB for the heaviest here).
- Licensing: 8 of 10 use AGPL-3.0; check the rest individually if you plan to modify and redistribute.
Every option here is open-source and self-hostable, tagged API within the groupware category. Deploy effort is graded from published container recipes, not vendor claims — see the methodology.