Jon Pretty

I am very happy to announce that will be speaking at Scala.io in Paris on 17 October! This will be my first conference talk since 2019, and I'm going to try to make it the best ever! I will introduce soundness.dev to the world: a tour de force of all the wonderful things you can do with Scala 3. I will show you an exciting, optimistic and realistic future for Scala. I will show you how to build CLI and web applications with code that's as easier to read than Python or JavaScript, but just as safe as Haskell. Thank you to the conference team for giving me this opportunity. Scala.io has a special place in my heart: it's always been a delightful, independent and friendly event, and I'm excited to be coming back to Paris! If you want to see the pinnacle of coding elegance, then please come along!

ExoBench MCP server is live in preview. Paste a slow SQL query into your AI tool. It rewrites the query, creates indexes, and iterates until performance improves using data from a REAL Postgres. Preview access is open now. Request an invite at exobench.ai

New version of #YAES is here, and this time it's huge! 🚀 We have a new integration with #Scala Jsoniter, a new testing library with primitives for testing the `Raise[E]` effect, a bunch of other stuff... and a new version of the `Reader[R]` effect based on opaque types 👻 With the new Reader, you can implement DI 🫛 with implicit resolution in your direct-style Scala applications. Here are the release notes: github.com/rcardin/yaes/r… Don't forget to check out also the example application that uses YAES from the ground up (WIP 😜): github.com/rcardin/functi… cc @petr_zapletal cc @ScalaTimes

@guizmaii Ship some upgrade instructions for LLMs with each release if you *really* want to be helpful to users.

I'd strongly argue that, now with AIs, the need for strong retro-compatibility in libraries is much less important If you use my libraries, don't expect too much. If I need to break retro-compatibility for my own personal needs, I will and it shouldn't be a problem to anyone

A go-to article if you want to start with Scala macros. It covers everything from top learning resources and compiler profiling to building better print utilities and shows exactly how to attach a JVM debugger to the compiler's process. Bookmark it 👇 halotukozak.github.io/posts/yes-you-…

Here's a little GitHub TUI for managing PRs. bunx @kitlangton/ghui github.com/kitlangton/ghui

Just tried Ox for Scala by @softwaremill. Direct-style code as readable as Python, but unlike Python, your method signature is the contract: type-safe, explicit, no surprises. No more deciphering flatMap chains. Turns out FP doesn't have to be complicated: Scala just needed direct-style. When the contract lives in the signature — not in a comment like in Python — AI coding agents get it right — not eventually, but by design.

Psst, there might be a free slot or two at the current round of mentorship program. Just saying. business4s.org/mentorship/

Claude Sonnet & Opus are really good at Scala. Quality code with minimal prompting. Works great for legacy stuff too. Replacing those painful Mockito unit tests with proper behavior-based integration tests was way easier than expected. Enables easy refactor for legacy code.

A cool new CLI tool which helps you discover running Scala-related processes. 📈 It would be awesome if it had an interactive mode so I could kill those zombies right from it! 🧟‍♂️

Deployed a first component using PureLogic to prod today. This is a view of the profiler (blur intentional) showing how clean the stack is compared to monadic effects. We already found something to optimize 😄

New blog post answering a question I was asked a couple weeks ago! Let's see how we can use PureLogic to model event-sourced domain logic in direct style while ensuring that state changes and emitted events always stay in sync. blog.pierre-ricadat.com/event-sourcing…

My other passion (besides Scala) is databases. There is an extension called pgmq, a message queue built on top of Postgres which can cover the scale for 99% of companies. To connect the two passions, I'm building a Scala client called pgmq4s. 🧵

Took me a while but the conversation series is now up on Spotify and Apple Podcasts! Search for "Rock the Code" and follow/subscribe, as more interesting conversations are coming soon.

Who would you like me to have as a guest?

Cellar lets you instantly query the public API of any Maven JVM dependency right from the terminal. 👇 github.com/VirtusLab/cell…

Uploaded the recording of my Scalar Warsaw presentation: Making Scala Scripting Actually Good with Mill youtube.com/watch?v=KRhLfz…

Attending @scalarconf was exhilarating. Great talks, lots of food for thought, and most of all, meeting and talking to many great people. There’s a lot of innovation going on in Scala right now, this is exciting. I leave with a lot of ideas. The coming months are gonna be busy!

I wanted to release Hearth 0.3.0 after Scala 3.3.8 is out, and Kindlings 0.1.0 after that. But overwhelmingly positive reception (and a horse head in my bed) convinced my to release them much earlier, so...

My slides are up here: slides.indoorvivants.com/scalar-2026

Just gave my talk at @scalarconf about a new way to deal with Protobuf in Scala. Couldn't be there? No worries, here's a blog post version of the talk! blog.pierre-ricadat.com/protobuf-goes-…