Scala Talks: Diffs for humans and AI agents & Scala 3 Macro annotations

🎉 Come along to the London Scala Talks! 🎉 In this event you'll hear from Jacob Wang and Dmytro Mitin.

Agenda 6:00pm - 🥤 Doors open. Come along and grab a drink! 6:40pm - 🗣️ Jacob Wang: Difflicious - Diffs for humans and AI agents 7:20pm - 🍕 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 - 🗣️ Dmytro Mitin: Can Scala 3 Have Macro Annotations Again? Rebuilding Macro Paradise 8:30pm - 🥤 Socialising: Grab a drink and let's discuss the talks. 9:00pm - 🍻 Join us in a pub to discuss the talks!

🌐 This event may have a live stream Watch this space for more details.

🗣️ 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!)

⭐ Jacob Wang ⭐ 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.

🗣️ 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.

⭐ Dmytro Mitin ⭐ 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.

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