Log message:
devel/hs-atomic-counter: import hs-atomic-counter-0.1.2.3

This package defines Counter type that can be safely modified concurrently from
multiple threads. The type supports only few operations, namely read, write, cas
(compare and swap), add, subtract and a few bitwise ones like or, and xor.

Most common use case is having a shared counter that multiple threads increment.
Another potential use case is lightweight locks.