Penrith Workshop

Typelevel Workshop in the Lake District

September 14, 2016 at Rheged Centre, Penrith

About the Workshop

A day of talks & unconference, co-located with Scala World.

The full set of sessions and topics will be decided by the participants on the day of the workshop. To give us some context, and provide introductions for possible sessions on the day the following attendees have kindly offered to do short informal presentations at the beginning of the day,

Dave Gurnell — State of the Mewnion

In this talk Dave will introduce the wonderful State monad: what it is, how it works, and how to use it to publish books and compose songs using cat noises.

Rüdiger Klaehn — abc

Rüdiger will introduce abc, an experiment in writing a tiny collections library that is more friendly to type classes. He will talk about the library itself and also about the projects structure and pain points when using type classes in scala. We can dig deeper during the unconference.

Eda Meadows — Monadic Wack-A-Mole

Working with code structured as monads can start out looking beautifully straightforward but as things develop you find yourself with for/yields that don’t compile as you have a random type that doesn’t match up. Eda will sketch out some ideas on how to deal with this which we can explore during the unconference.

Miles Sabin — Typelevel Scala rebooted

Following on from the fix for SI-2712 the Typelevel Scala project has been reinvigorated. Miles is going to give a quick overview of what Typelevel Scala adds to Lightbend Scala and set the scene for unconference sessions on using it in your projects today and contributing to Typelevel and Lightbend Scala development.

Paweł Szulc — The Cats toolbox: a quick tour of some basic typeclasses

It’s happened to all of us: we ran away from some conversation or library because it kept on using those “weird” phrases. You know, like “type classes”, “semigroups”, “monoids”, “applicatives”. Yikes! They all seem so academic, so pointlessly detached from real-world problems. But then again, given how frequently we run into them in functional programming, are they REALLY irrelevant, or do they have real-world applications? Paweł will start helping us make sense of the gobbledygook and we can continue in a later session.

Pere Villega — What happens when you use Free Monads

There’s a lot of talk about Free Monads and how awesome they are. But, what happens when we try to implement a real application using Free? Pere will show ane example using Freek and the StockFighter API and highlight some of the choices and limitations involved. Later, during the unconference, we can experiment with Free Monads to see their impact in everyday concerns like testing, program design, etc.

Dick Wall — Ensime Sublime

Ensime isn’t just for Emacs! Dick Wall will give us a taste of what’s been happening in the Ensime project to support users of the Sublime Text editor and encourage you all to hack on Ensime later.


This event took place at the Rheged Centre, situated near Penrith in the Lake District National Park, UK.