Team calendar
See who's out at a glance. Weekly and monthly views with leave-type color coding and emoji icons.
Team leave planning,
beautifully simple
An open-source leave management app for small and mid-size teams. Self-hosted, customizable, and ready in minutes.
Features
Everything your team needs to manage time off
No spreadsheets, no email chains. Just a clean interface your entire team will actually use.
Two-factor authentication
Optional TOTP two-factor, with backup codes for when you lose your phone. Your secret is encrypted at rest and only decrypted to verify a code.
Role-based access
Three roles out of the box: Admin, Manager, and Employee. Each sees only what they need.
Dark mode & themes
Four color palettes (Warm Teal, Sage Green, Sunset Warm, Soft Lavender) plus light, dark, and system theme.
Mobile-ready
Fully responsive layout with bottom navigation, swipe-friendly calendar, and optimized touch targets.
Public holidays
Auto-import public holidays per country via Nager.Date API. Supports multiple country calendars simultaneously.
One-click approvals
Managers approve or decline requests from the dashboard or directly from a Slack notification.
Personalization
Make it yours
Choose from four hand-crafted color palettes and switch between light, dark, or system themes. Every user picks their own preference.
Warm Teal
Default palette
Sage Green
Earthy tones
Sunset Warm
Coral accent
Soft Lavender
Cool & calm
Integrations
Connects with the tools you already use
Notifications, calendar sync, and automatic holiday data, all out of the box.
Slack
Leave request notifications, approval actions, and weekly team digests, delivered straight to your Slack channels.
Built-iniCal feeds
Subscribe to team absences from Google Calendar, Apple Calendar, Outlook, or any app that supports iCal.
Built-inPublic Holidays API
Automatic import of country-specific public holidays via Nager.Date. Supports DE, FR, NL, and 100+ more countries.
Built-inOpen Source
Free forever. AGPL-3.0 licensed.
Who's OOO is a Symfony 7.4 / PHP 8.5 application backed by MySQL 8.4, fully open source under AGPL-3.0. Deploy on fortrabbit for €4.5/month or run it anywhere with Docker Compose. Audit the code, extend it to fit your workflow. No vendor lock-in, no subscription fees.
Use it freely. If you modify and redistribute, share your changes under the same license.
Build in public
I build Who's OOO in the open
When you self-host an app, you're trusting whoever built it to run on your own server. So here's me. I build Who's OOO live on YouTube. If you want to see who's behind the code before you deploy it, this is the most honest way I can show you. Watch a stream, ask questions, follow along if it's useful.
Need help getting started?
Setup & configuration service
Hi, I'm Igor, the creator of Who's OOO. I built this as a personal open-source project, and we use it daily at fortrabbit to manage our own team's leaves. I offer a one-time paid setup service to help you get up and running quickly, with no ongoing fees or subscriptions.
- Server deployment and initial configuration
- Slack workspace integration setup
- Custom leave types, holiday calendars, and team onboarding
- Theme customization and branding to match your company
Trusted by teams at
Ready to simplify leave planning?
Deploy Who's OOO on fortrabbit or your own server and have your team set up in minutes.
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