Intro and motivations


Scala is a static-typed language, and Slack Morphism provides methods and models definitions for most of the methods and structures of Slack Web/Events API. There is a well-typed DSL to build your messages and views with Slack blocks safely as well.

Easy to use

While Slack Morphism uses some of FP paradigms and mostly avoids imperative style and mutable states internally, its API doesn’t expose your app anything that might make you learn additional advanced frameworks (like ZIO, cats-effects, and others). It provides you with a simple API with the support for Scala Future, Option, Either, etc. If you’re into pure functional concepts, there is support for cats-effect IO as well.


Slack Morphism core library intentionally avoid dependencies to any additional Web-frameworks, so you free to use any framework you’re familiar with. Slack Morphism doesn’t have any dependencies to any particular HTTP client library either and uses sttp library to give you choice.

However, it would be an incomplete solution to provide you only core components, and for a quick start, there are full-featured giter8 templates and examples for:

You can browse source codes of examples (without installing them) here.

Non-blocking and Reactive

All of the Slack Morphism API methods available in a non-blocking manner, and some of them (e.g. returning Slack channel history) also have support for reactive frameworks (Reactive Stream, FS2).

Rate controlling and throttling access to Slack Web API

There is ready to use a rate control/throttling implementation, which follows the Slack API rate limits and tiers (or your custom configuration).


Slack Morphism doesn’t provide:

  • RTM API (the usage of which is slowly declining in favour of Events API)
  • Legacy Web/Events API methods and models (like Slack Message attachments, which should be replaced with Slack Blocks)