Both are geocoders using OpenStreetMap data and backed with Elasticsearch. The main difference is how they handle geographical context, eg to determine in which

Both are geocoders using OpenStreetMap data and backed with Elasticsearch. The main difference is how they handle geographical context, eg to determine in which city/region each place is located. Which is useful both for indexing the data and producing human-readable labels. Pelias is using its own gazeteer (https://whosonfirst.org/ https://whosonfirst.org/) to index locations and remarkable zones. Whereas Mimirsbrunn relies only on OSM data for this task using Cosmogony (https://github.com/osm-without-borders/cosmogony https://github.com/osm-without-borders/cosmogony), a tool that extracts official administrative boundaries and other shapes from OSM data. But the world is a complicated place, and OSM tagging scheme doesn't always lend itself to geocoding purposes. So it comes with a lot a caveats which are still being working on :)