After an overview of cats-effect which deals with single effect it feels natural to have a look at fs2 and see how multiple effects can be combined into a stream. As we’ve covered some common streaming patterns with Akka stream a while ago it’ll be interesting to see how they compare with each other.
Category archives: Programming
Cats-effect, an overview
After many applications written using Scala’s Futures, Akka Actors or Monix,… Cats-effect is now my favourite stack to write Scala programs. Why is that? Well, it makes your code easier to write and reason about while providing good performances.
Dealing with errors
As a programmer we don’t really like to deal with errors. We like to focus on the happy path – the one that provides value – and deal with the errors later because … well, we have to do it! However dealing with failures is crucial if we don’t want our program to stop on […]
Leveraging the type system to avoid mistakes
We all know we should write tests to make sure our system behaves as it is supposed to. Surely tests are necessary to ensure correctness of our programs but they only depend on what the programmer is willing to test (or can think of testing). What I mean is that there will always be gaps […]
Refined types, what are they good for?
Type refinement is all about making the types more precise. But why would do that? Because using the correct types makes your program safer as you reduce the possibility to introduce bugs. First let’s think about types. For instance String is a type we use all the time. A variable of type String can have […]
Akka stream interface for gRPC
Back from holidays let’s continue with some of my favourite topics: AkkaStreams and gRPC. We’ve already seen how can take advantage of the ScalaPB code generation tool to generate new interfaces (GRPCMonix) on top of the grpc-java implementation or to create new tools to integrate gRPC with other services (GRPCGateway). Similarly to GRPCMonix which provides […]
Introduction to Tagless final
In this previous post we’ve seen that before using Scala’s Future it might be worth taking some time to think of the use cases (especially error cases), the execution model we need, … as it might be more advantageous to choose a solution like Monix’s Task (although not available in standard library) to gain finer […]
Scala Futures vs Monix Tasks
In this previous post we saw how Scala Futures work and why they need an implicit ExecutionContext to run their computation. While there is some trick to pass the ExecutionContext, it’s usually cumbersome and clutter the code. So the question really is: Do you need an ExecutionContext everywhere? Well, you do as long as you […]
Understanding Scala Futures and Execution Contexts
Viktor Klang recently published a set of useful tips on Scala Futures. While being widespread and heavily used, people (especially newcomers) are still experiencing problems working with Scala Futures. In my opinion many of the problems come from a misunderstanding or misconception on how Futures work. (e.g. the strict nature of Futures and the way […]
gRPC in Scala
As many might think, gRPC doesn’t stand for “google Remote Procedure Call” but is a recursive acronym meaning “gRPC Remote Procedure Call”. I don’t know if you buy it but the truth is that is was originally developed by Google and then open-sourced. If you’ve been in the IT for a while RPC doesn’t necessarily […]