I’ve built a new hobby project. Geodesy is a quick spatial search engine for the EPSG Geodetic Parameter Registry - https://geodesy.appspot.com.
It’s built with Vue.js as a front-end only app. The database is built from static JSON and TXT files using data structures picked for fast spatial queries of a large dataset. This database is built by Node scripts from the EPSG’s own datafiles.
It’s then deployed onto Google App Engine using a simple Python webapp2 handler to serve up the files.