Talks & Drinks with John de Goes

Public group
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Note that is a joint event with Amsterdam.scala, so please RSVP only once.

John de Goes will join us this evening for an inspiring talk!

Title: The Death of Final Tagless

Final tagless. The topic strikes fear into the hearts of Scala developers everywhere—and not without reason. Final tagless allows developers to build composable Domain Specific Languages (DSLs) that model interaction with the outside world. Programs written using the final tagless style can be tested deterministically and reasoned about at compile-time. Yet the technique requires confusing, compiler-choking higher-kinded types, like `F[_]`, and pervasive, non-inferable context bounds like `F[_]: Concurrent: Console: Logging`. Many have looked at final tagless and wondered if all the layers of complexity and ceremony are really worth the benefits.

In this presentation, John A. De Goes provides a gentle and accessible introduction to final tagless, explaining what it is and the problem it intends to solve. John shows that while final tagless is easier to use than free monads, the technique suffers from a litany of drawbacks that push developers away from functional programming in Scala. John then introduces a novel approach that shares some of the benefits of final tagless, but which is idiomatic Scala, easy to explain, doesn’t need any complex type machinery, provides flawless type inference, and works beautifully across Scala 2.x and Scala 3.

Come join John for an evening of fun as you learn how to write functional code in Scala that's easy to test and easy to reason about—all without the complexity of free monads or final tagless.

18:00 Food & Drinks (door opens at 18:00, food will be served from 18:15 onwards)
19:00 John de Goes
20:00 Drinks
21:00 End