// the find
alyssaxuu/mapus
A map tool with real-time collaboration 🗺️
Mapus is a self-hosted collaborative map annotation tool built on Leaflet and Firebase Realtime Database — essentially Google MyMaps with live presence. You draw, drop markers, trace paths, and watch collaborators move around in real time. It's a weekend-project-turned-polished demo, not a production system anyone is actively maintaining.
Last commit was 2022 and the issue tracker is presumably full of unaddressed reports, but the feature set it shipped is genuinely solid for a solo project: GeoJSON export works, the drawing tools (Leaflet Geoman) are well-chosen, and the Firebase Realtime Database choice actually fits the use case — presence and map state sync well over WebSockets. The README is unusually honest about limitations and future ideas rather than overselling what it is.
Firebase Realtime Database is hardwired — there's no abstraction layer, so swapping to a self-hosted backend (Supabase, your own WebSocket server) means rewriting the sync logic throughout main.js. The entire app is a single HTML file plus one JS file with no build step, which makes it easy to run but nightmarish to extend or test. Security is explicitly punted — the README tells you the default Firebase rules are fine for development but doesn't give you production rules. And it's been unmaintained for over three years, so Leaflet and Firebase SDK versions are stale and the Nominatim ToS around autocomplete has drifted further since this was written.