Uses libpq implement the arsd.database.Database interface.
Requires the official pq library from Postgres to be installed to build and to use. Note that on Windows, it is often distributed as libpq.lib. You will have to copy or rename that to pq.lib for dub or dmd to automatically find it. You will also likely need to add the lib search path yourself on both Windows and Linux systems (on my Linux box, it is -L-L/usr/local/pgsql/lib to dmd. You can also list things your app's dub.json's lflags too. Note on the Microsoft linker, the flag is called /LIBPATH.)
For example, for the default Postgres install on Windows, try:
"lflags-windows": [ "/LIBPATH:C:/Program Files/PostgreSQL/<VERSION>/lib" ],
In your dub.json.
When you distribute your application, the user will want to install libpq client on Linux, and on Windows, you may want to include the libpq.dll in your distribution. Note it may also depend on OpenSSL ssl and crypto dlls and libintl.dll as well. These should be found in the PostgreSQL lib and/or bin folders (check them both!).