Pure logging library for cats-effect


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Deprecation notice!

See entire docs at microsite.

iolog4s is no longer maintained. It has been completely integrated into log4cats as of its version 0.0.5. I highly recommend you use that instead.

The reason behind this is quite simple, both iolog4s and log4cats have appeared on the scene at roughly the same time, and we decided to merge the effort of creating a logging library for the typelevel ecosystem.


iolog4s is a logging library for scala that suspends all your logging side-effects into your chosen cats.effect.Sync instance, e.g.:

iolog4s has the same interface as log4s, except all return types are of type F[Unit] where F[_]: Sync.

super-quick start

Avaialble for scala versions 2.11, and 2.12.

"org.iolog4s" %% "iolog4s" % "0.0.4"

You also need to depend explicitly on a backend for logging, e.g.:

"ch.qos.logback" % "logback-classic" % "1.2.3"