I am looking for a GIS platform which supports dynamically updating layers. These could be updated by file, socket, plugin, or any other measure, that isn't important.
The goal is to be able to draw shapes on a map and update those shapes via an external program, with the results being sent (or written to file) to a GIS application which would update its layers accordingly. Instant updates aren't vital, if the GIS application checks on a timer that is acceptable.
I've spent some time searching and poking through the docs on things like QGIS and I haven't found anything definitive that supports this functionality. The "monitor layer" option on delimited layers in QGIS is along the lines of what I want, I think, but the map will only update upon a manual action from what I can tell.
Dynamic updating of layers through an external process is the most important requirement for this small project and far outweighs other GIS capability considerations.