Implementing OHMG

OHMG is open source software that could, technically, be self-hosted for your own georeferencing projects. The most up-to-date installation instructions can be found in ohmg-dev/OldInsuranceMaps.

However, it is still entwined with the installation at OldInsuranceMaps.net, so generic installations of it have yet to be realized. Please stay in touch to keep up-to-date if this interests you!

• Issue/bug tracker: github.com/ohmg-dev/OldInsuranceMaps/issues
• Newsletter (and archive): oldinsurancemaps.net/news/
• Discussion forum: https://forum.openhistoricalmap.org/c/oldinsurancemaps/13

About the software stack​

OHMG uses the Django web framework for URL routing, auth, and the ORM, and Django Ninja to create an API. A newsletter is implemented with Django Newsletter.

The frontend is built (mostly) with Svelte, using OpenLayers for all map interfaces. OpenStreetMap and Mapbox are the basemap sources.

Other components include:

• Postgres + PostGIS
  • Database
• GDAL (3.5+ release)
  • A dependency of PostGIS, and also used directly for all warping/mosaicking operations.
• Celery + RabbitMQ
  • Background task management (a handful of loading/splitting/warping processes run in the background)
  • Presumably, Redis could be used for the broker instead of RabbitMQ.
• TiTiler
  • Tileserver for georeferencing COGs (Cloud Optimized GeoTIFFs)