What system of reference is used for positions in traccar?
Coordinates are converted by the web app for displaying on the map.
Conversion from what reference system? Can I assume safely that the rest endpoints will always use Wgs84?
Yes, the API always returns WGS84.
I use traccar as part of our infrastructure. Several devices report their positions to the server. I want to know if there's any conversion taking place to modify these positions on the fly from/to WGS84 to/from EPSG:3857.