In favour of


A "PostgreSQL" backend for the "hasql" library

Version on this page:
LTS Haskell 3.22:0.10.6
Stackage Nightly 2015-12-14:0.10.6
Latest on Hackage:0.10.6

See all snapshots hasql-postgres appears in

MIT licensed and maintained by Nikita Volkov
This version can be pinned in stack with:hasql-postgres-,6718

Module documentation for

This library provides a "PostgreSQL" driver for the "hasql" library.

It supports all Postgres versions starting from 8.3 and is tested against 8.3, 9.3 and 9.4 with the integer_datetimes setting off and on.

According to the included benchmarks, it performs up to 2x faster than "postgresql-simple" and up to 7x faster than "HDBC". You can read up a post with analysis of those benchmarks.


  • “attoparsec”-0.13 support


  • GHC 7.10 support


  • JSON support


  • Update the “backend” dependency

0.10.0 - Major overhaul

  • Transactions now are only retried in case of the “serialization_failure” (40001) error


  • The Unknown type got implemented


  • The unit result handler no longer fails on statements, which do produce results
  • The dependency on “list-t” got relaxed
  • The dependency on “either” got restricted