The pure asynchronous runtime for Scala (by typelevel)

Cats-effect Alternatives

Similar projects and alternatives to cats-effect

NOTE: The number of mentions on this list indicates mentions on common posts plus user suggested alternatives. Hence, a higher number means a better cats-effect alternative or higher similarity.

cats-effect reviews and mentions

Posts with mentions or reviews of cats-effect. We have used some of these posts to build our list of alternatives and similar projects. The last one was on 2022-10-13.
  • Should I Move From PHP to Node/Express?
    13 projects | | 13 Oct 2022
    On the contrary, switching to the functional mindset, with something like Typelevel Scala3 and respective cats and cats-effect fs2 frameworks, helps to rethink a lot of designs and development approaches.
  • Next Steps for Rust in the Kernel
    8 projects | | 21 Sep 2022
    I think "better Haskell on JVM" (in contrast to "worse Haskell") is a good identity for Scala to have. (Please note that this is an intentional hyperbole.)

    Of course, there are areas where Haskell is stronger than Scala (hint: modularity, crucial for good Software Engineering, is not one of them). And Scala has its own way of doing things, so just imitating Haskell won't work well.

    Examples of this "better Haskell" are and .

    All together, Scala may be a better choice for you if you want to do Pure Functional Programming. And is definitely less risky (runs on JVM, Java libraries interop, IntelliJ, easy debugging, etc...).

    None of the other languages you mentioned are viable in this sense (if also you want a powerful type system, which rules out Clojure).

    I agree that Rust's identity is pretty clear: a modern language for use cases where only C or C++ could have been used before.

  • Java 19 Is Out
    4 projects | | 20 Sep 2022
    I would use Scala. I like FP and Scala comes with some awesome libraries for concurrent/async programming like Cats Effect or ZIO. Good choice for creating modern style micro-services to be run in the cloud (or even macro-services, Scala has a powerful module system, so it's made to handle large codebases).

    The language, the community and customs are great. You don't have to worry about nulls, things are immutable by default, domain modelling with ADTs and patter matching is pure joy.

    The tooling available is from good to great and Scala is big enough that there are good libraries for typical if not vast majority of stuff and Java libs as a reliable fallback.

  • Scala isn't fun anymore
    10 projects | | 10 Sep 2022
    The author is the creator of Monix and implemented the first version of cats-effect. He knows what he is doing.
  • Question about some advanced types
    3 projects | | 5 Sep 2022
    You want Kernmantle, which quite honestly shouldn't be hard to implement around Cats and cats-effect. In particular, although Kernmantle doesn't require the use of the Arrow typeclass, there happen to be Arrow (actually ArrowChoice) instances for both Function1 from the standard library and Kleisli from Cats itself, given a Monad instance for the Kleilsi's F[_] type parameter. In other words, we should be able to port Kernmantle from Haskell to Scala (with the Typelevel ecosystem) and instantly be able to use pretty much anything else from the Typelevel ecosystem, or wrapped with it, in our workflow graphs. Pure functions, monadic functions, applicative functions, GADTs with hand-written interpreters, any of it. I think this would be eminently worth doing.
  • A Python-compatible statically typed language erg-lang/erg
    27 projects | | 13 Aug 2022
  • Cats vs ZIO
    2 projects | | 10 Jul 2022
  • Rust Is Hard, Or: The Misery of Mainstream Programming
    15 projects | | 2 Jun 2022
    Scala. With the functional effect systems, like Cats Effect or ZIO, you get superpowers.

    Not only can write programs that are "async", but you also get easy retries (and other tricks), safe refactorability (because of its Pure FP nature), reliable and painless resource management and some other goodies like STM (Software transactional memory).

    It's really that good.

  • I love Scala but I can't stand:
    4 projects | | 27 Mar 2022
    So limited, so many landmines, eg
  • Trying to decide on Scala or Kotlin
    7 projects | | 20 Mar 2022
    Cats Effect is a high-performance, asynchronous, composable framework for building real-world applications in a purely functional style
  • A note from our sponsor - Zigi | 29 Nov 2022
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