Hello. I published a library “postgresql-pure”, which is a PostgreSQL driver written in pure Haskell, a few days ago. This library is developed to aim: - to increase the performance on multi CPU core environments - to run on multi platform - to build it easier especially on Windows to remove the dependency on libpq, which is made by C - there is postgres-wire which is a fast implementation but it doesn't support Windows I confirmed that: - the performance was proportional to the number of cores - the performance on 12 cores were 28% better than postgres-wire, 300% better than postgresql-simple Both test cases are simple constant value queries like “SELECT 2147483647 :: int4, …” to decrease server's load. I'm writing a report about this development and I will send email again. Please try this and feel free to report issues. Best, Kazuki Okamoto Hackage: http://hackage.haskell.org/package/postgresql-pure GitHub: https://github.com/iij-ii/postgresql-pure