About us
Come and meet other software developers in the London area interested in the Scala programming language.
Follow us:
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LondonScala on LinkedIn
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[@londonscala.bsky.social](https://bsky.app/profile/londonscala.bsky.social) on Bluesky
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@LondonScala on X and use the hashtag #LondonScalaUG
Upcoming events
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Scala Talks: Diffs for humans and AI agents & Scala 3 Macro annotations
Medidata, 12 Hammersmith Grove, London, GBπ Come along to the London Scala Talks! π
In this event you'll hear from Jacob Wang and Dmytro Mitin.Agenda
6:00pm - π₯€ Doors open. Come along and grab a drink!
6:40pm - π£οΈ Jacob Wang: Difflicious - Diffs for humans and AI agents
7:20pm - π Intermission: Join us for some free food and drinks! Vegan, vegetarian options are provided. Let us know if you'd like something special - we'd be happy to accommodate.
7:50pm - π£οΈ Dmytro Mitin: Can Scala 3 Have Macro Annotations Again? Rebuilding Macro Paradise
8:30pm - π₯€ Socialising: Grab a drink and let's discuss the talks.
9:00pm - π» Join us in a pub to discuss the talks!π This event may have a live stream
Watch this space for more details.π£οΈ Jacob Wang: Difflicious - Diffs for humans and AI agents
Scala is used in applications with complex domain logic,
and with that often means big comparison failures that is difficult to decipher.
Difflicious is a Scala library/toolkit for diffing Scala objects:
- Structured diff results pin-points the parts of the objects that are different
- Configurable diffing methods (e.g. Compare a List order-independently)
In this talk, we'll walk through Difflicious' various features and show you how
it can improve your development workflow (and your AI agents', too!)β Jacob Wang β
Jacob has been writing Scala for close to 10 years. He enjoys creating programs that mostly
behave, as well as sharing this joy via open source & teaching.π£οΈ Dmytro Mitin: Can Scala 3 Have Macro Annotations Again? Rebuilding Macro Paradise
Scala 2's Macro Paradise allowed annotations to transform definitions and generate members, companions and other definitions before ordinary typechecking. Scala 3 has an experimental macro-annotation API, but newly generated definitions are visible only within the macro expansion.In this talk, we'll explore another approach: a pre-typer compiler plugin that brings back Paradise-style source transformation. We'll see where it fits into the Scala 3 compiler, how generated definitions become visible to ordinary typing, and how quasiquotes can make such transformations easier to write.
β Dmytro Mitin β
Dmytro Mitin is a Scala and Haskell developer and mathematician interested in functional programming, type systems, metaprogramming and compilers. He has taught Scala through online courses, answered extensively on Stack Overflow, and contributed to open-source projects including the Scala 3 compiler, Shapeless and ProvingGround. His current open-source work explores Scala 3 macro annotations, quasiquotes and semantic tooling.ββββββββββββββββββββ
π£οΈ Would you like to present, but are not sure how to start? Give a talk with us and you'll receive mentorship from a trained toastmaster! Get in touch through this form and we'll get you started
π‘ Interested in hosting or supporting us? Please get in touch through this form and we can discuss how you can get involved.
π All London Scala User Group events operate under the Scala Community Code of Conduct.
We encourage each of you to report the breach of the conduct, either anonymously through this form or by contacting one of our team members. We guarantee privacy and confidentiality, as well as that we will take your report seriously and react quickly.34 attendees
Scala Workshop: Building Real Applications in Scala Native
Raindrop, 52 Tabernacle Street, London, EC2A 4NJ, London, GBπ Come along to a London Scala Workshop! π
Bring your laptop and learn from Noel Welsh on building Real Applications in Scala Native.
Agenda
6:10pm - π₯€ Doors open. Come along and grab a drink!
6:30pm - π» Workshop: Building Real Applications in Scala Native
7:30pm - π Intermission: Join us for some free food and drinks! Vegan, vegetarian options are provided. Let us know if you'd like something special - we'd be happy to accommodate.
8:00pm - π» Keep hacking!
9:00pm - π» Join us in a pub to discuss the workshop!π£οΈ Noel Welsh: Building Real Applications in Scala Native
Scala Native is great! It creates small and fast binaries, and can access all operating systems features. This workshop will introduce working with Scala Native by building a terminal based application. We'll learn how to setup and build Native code, call into with system libraries, and use the archaic but powerful features of the terminal.π» Set up before coming
You must have Scala Native installed before the workshop. Scala Native requires some additional installation steps beyond installing just Scala. Furthermore, the operating system specific features we will use are only available in Unix-like systems (Linux or MacOS). If you are using Windows then you must be able to use WSL.You can find more details on the Scala Days workshop page.
β Noel Welsh β
Iβm a principal at Inner Product, where I help companies succeed in their software projects. Iβve written several books on programming, the most recent being Functional Programming Strategies. I maintain open source projects at Creative Scala.
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π£οΈ Would you like to present, but are not sure how to start? Give a talk with us and you'll receive mentorship from a trained toastmaster! Get in touch through this form and we'll get you started
π‘ Interested in hosting or supporting us? Please get in touch through this form and we can discuss how you can get involved.
π All London Scala User Group events operate under the Scala Community Code of Conduct.
We encourage each of you to report the breach of the conduct, either anonymously through this form or by contacting one of our team members. We guarantee privacy and confidentiality, as well as that we will take your report seriously and react quickly.17 attendees
Typelevel Open Source Hack
SiriusXM, 36 High Holborn, London, GBCalling all Scala enthusiasts! Join us for a fun night of hacking, collaborating, and contributing to Typelevel open-source projects. Whether youβre a seasoned Scala developer or just getting started, this is the perfect opportunity to level up your skills, meet like-minded coders, and contribute to Open Source!
Agenda
10:00am - π₯ Doors open. Come along, mingle and grab some breakfast.
10:30am - π» Quick introduction & find your hackmates!
1:00pm - π₯ Lunch: Join us for some free food and drinks! Vegan and vegetarian options are provided. Let us know if you'd like something special - we'd be happy to accommodate.
2:00pm - π» Keep hacking!
3:30pm - π₯€ Join up and share what we've been working on.
4:00pm - β Join us in a coffee shop to keep going!What will happen on the day?
After a quick introduction, we will help everyone find a project they want to work on and disperse into groups.
At end of the afternoon we'll gather up and share what we've done and learned that day :)Frequently Asked Questions
I am a novice Scala developer, is this the right event for me? π
Yes! One of the best ways to improve your Scala skills is by working on Open Source library and projects!I don't know what projects I should contribute to.. βοΈ
We have a list of Typelevel-related projects that would love to have some contributions. Other than get-work-done libraries, we have cool projects like game engine, frontend framework, synthesiser!I have an idea for a Open Source project but it's a bit daunting. Can you help? ποΈ
Yes! We'd love to see more open source Scala projects and contributors! We can help you get started and provide technical guidance whenever you need it.Help! I'm stuck outside the building / somewhere!
Joining our discord is probably the best way to be heard!Discord server invite link:
https://discord.com/invite/aRCVCHmHESDonations
The Typelevel foundation is a charity and is looking for funding! You can donate to it via Global Giving.
---π This event operates under the Typelevel Code of Conduct: https://typelevel.org/code-of-conduct/.
We encourage each of you to report the breach of the conduct, either anonymously through this form or by contacting one of our team members. We guarantee privacy and confidentiality, as well as that we will take your report seriously and react quickly.22 attendees
Past events
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