Bitstring is a project mainly written in Haskell, based on the View license.
A lazy bitstring library for bit parsing
This is a library for working with data on the bit-level. The interface looks pretty much like a ByteString, which is exactly what it is underneath. This library also provides an alternative implementation of the BitGet monad, as found in Data.Binary.Strict. However, this one is lazy, as is the library in whole.