@dlsniper I installed PostGIS extension in the container image.
ubuntu@box16:~$ psql -c 'CREATE EXTENSION postgis;'
CREATE EXTENSION
ubuntu@box16:~$ psql -c 'CREATE EXTENSION postgis_topology;'
CREATE EXTENSION
ubuntu@box16:~$ psql -c 'CREATE EXTENSION fuzzystrmatch;'
CREATE EXTENSION
ubuntu@box16:~$ psql -c 'CREATE EXTENSION postgis_tiger_geocoder;'
CREATE EXTENSION