Clever°Maps’ is a three years old startup based in the Czech Republic. We create web apps for four distinct market segments:
All our activities take advantage of PostgreSQL as a great DBMS and PostGIS as a tool to query data our apps need. These days we keep a complete monthly updated copy of the whole Czech cadastre together with LPIS (Land Parcel Identification System), that is more than 650 GB of data. We use PostGIS for much more than simple queries (although talking millions of parcel lots it is hard to tell them simple anymore):
Recently our BI team pushed the limits of PostgreSQL/PostGIS trying to use it on ~180M rows of spatial data. They eventually ended up using Amazon Redshift, but the whole geoprocessing is still done in PostGIS beforehand.
Nautilytics is a small data visualization and GIS startup based out of Boston, MA. We use PostGIS and PostgreSQL, among other open-source tools to build powerful web applications for US government organizations, public, and private sector companies.
I used extensively postgis (+ecosystem) for my phd thesis, in several ways. The first is that PostGIS is a good steady horse (elephant?): a database is the perfect place to store a lot of very different information in the same place and put them in relation. For geospatial data, postgis means you always have a way to put data in relation (are they at the same place?).
The Urban Center for Computation and Data (UrbanCCD) is a research initiative of Argonne National Laboratory and the Computation Institute of the University of Chicago. We create computational tools to better understand cities. One of these is Plenario, our hub for open geospatial data. PostGIS makes the spatial operations at the heart of Plenario possible.