I had been following tidwall/tile38 for a while already, too without a clear use case for actually using it. When we refactored a main part of our code base the use case finally arose;-)

At this point we're about to release tile38 to our staging environment. We opted for it basically for its capability to cache and spatially query geojson directly. Plus this can be done without the serialisation/deserialisation overhead. Another advantage for us is the ability to use the python-redis bindings. This let's us execute commands like this to retrieve data for a tile x,y,z request:

res = client.execute_command( "INTERSECTS", our_key, "WHERE", "minzval", 1, z, "LIMIT", LIMIT, "TILE", x, y, z )

Very straightforward and very fast.

Using its geofencing, which is awesome! Not ready for prod yet, and I'll open-source the code;

I started building a generic geofence gRPC framework on top of tile38. You get a gRPC service that abstracts away the Redis API from you, and is generic enough to run multiple applications from the same tile38 server. It works by namespacing keys into their own collection. The namespacing is done through authentication with the header metadata, so it becomes transparent to the gRPC client.

I'm

* sending a notification every time the bus is x km/miles from someone (static geofences), * triggering certain actions when user's at a train station (in conjunction with Google/Android geofencing)

I have been trying to use roaming geofences, but don't really have much use for them at the moment.

shameless plug

at https://www.weenect.com we're currently experimenting with it in order to replace our mongodb, I think I will go with this and a mix of postgresql for historical data.

the realtime geofencing capabilities will be a very good plus for us, as that's one of the main feature of our products, i.e being able to know when your cats or dog is going too far.

very cool! I built a small gsm/gps tracker for my motorcycle a few years ago. Its an interesting space.

It's nice but it's kind of limited to simple apps. No polygon or geocorridor points of interest and you'd need a database anyway to store historic data. For anything more complex tgan point on map apps, I'd use PostgreSQL + PostGIS.

I'd love to see something that makes use of realtime geofence hooks http://tile38.com/commands/sethook/

I think you can write a trigger procedure and use the listen/notify mechanism for notifications. Both exist since 9.3.

https://www.postgresql.org/docs/current/static/plpgsql-trigg...

https://www.postgresql.org/docs/current/static/sql-listen.ht...

Web-based notification is pretty much trivial after that since you need a database client written in a language of your choice that forwards the notification via HTTP to some endpoint. It's not as trivial as the tile38 but it can be more powerful since you can add any type of geometry to your POI. For instance you want to be notified when a vehicle crosses state borders.