Haskell Utrecht Meetup

UPDATE: Due to the change in COVID-related government regulations, we will unfortunately have to move this event. We will let you know as soon as we have got a new date. We are as disappointed as you!

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This is the inaugural get-together of Haskell Utrecht! We are going to kick it off with some pizza followed by two talks, including time for questions and to get to know each other.

We will meet at the new office of Channable who have mostly kindly volunteered to host us — thank you, Channable!

We hope to see you there!

Tentative agenda:

18:00: Doors open
18:30: Pizza (courtesy of Channable)
19:00: Welcome
19:15: Jeroen Bransen (Chordify), "Type-safe Redis caching at Chordify"
20:00 Break
20:15: Manuel Chakravarty (Tweag & IOG): "Haskell on Cardano"

== Type-safe Redis caching at Chordify ==

Chordify is a popular music education platform, with a Haskell backend that handles hundreds of requests per second. To handle these requests efficiently, Redis is used as an in-memory cache. While Redis support various types of data, its type system is much more limited than Haskell's, so to work together with typed Haskell world and to prevent runtime errors, we have built a layer of Haskell code to deal with the interaction.

In this talk we present our Haskell-Redis layer, which supports strongly typed keys and values, transactions (which coincide with the Applicative class), multiple Redis instances, and locking. What we find interesting about this layer is that our usage of Redis is quite standard, and found in many pieces of imperative software too, but the composability and abstractions in our library make it easy for the programmer to create complex and bug-free interactions, which believe to be a bit less common.

== Haskell on Cardano ==

Cardano is one of the largest blockchain projects in existence and it focuses strongly on sustainability (don't burn the planet), financial inclusion (banking the unbanked), governance (let the community count the shots), and scientific rigor (the tech is based on a stack of peer-reviewed scientific papers). Cardano is also built on Haskell. The blockchain core (i.e., security-critical node software) is implemented in Haskell and the programmability layer (smart contracts) enables developers to extend the functionality of Cardano with Haskell code.

In this talk, I will explain why Haskell was chosen to implement Cardano. I will also explain why purely functional programming is a perfect fit for implementing blockchain contracts. Finally, I will argue that blockchains create the perfect conditions for rigorous software development and formal verification to flourish.