I've been building WebApps since 2014. Preferably using Python (Django, FastAPI, Flask, ...) backed by PostgreSQL and for frontend Typescript React (Next.js, create-react-app, ...) or Vue.
I also have a big interest in data piping and data visualisation in all of its forms.
Example project:
Once built a system that collected samples of Wifi probes from hundreds of nodes, triangulated the positions of the cell phones and stored the paths the cell phones have travelled. Then also built a data visualisation tool for it where the user could draw polygons on a map and then get visitor statistics.