Hi. I'm the maintainer of Npsgql, and I happened to see this report. Npgsql was removed from mono because it was severely out of date, and in today's .NET world the best practice is to install packages via nuget rather than installing them on the system (i.e. in the Global Assembly Cache or GAC). Is there a Debian policy about making .NET packages available as GAC-installing packages?
All this aside, the latest version of Npgsql is now 3.0.3 and not 2.2.7 which is apparently what's being published as a Debian. Shay