Nostr notes by matejcerny

Scala 3.3.9 is out, proving that the previous release line gets ...

2026-10-28T09:55:20Z

Scala 3.3.9 is out, proving that the previous release line gets serious upgrades - not just security patches. 🎉

Even with Scala 3.9 LTS available, 3.3 gains actionable compiler error messages, better Java type compatibility, new syntax warnings, and more. Plus, the sbt plugin to reduce Scaladoc size is no longer needed. 🙌

https://github.com/scala/scala3/releases/tag/3.3.9

Seeing so many security incidents last week made me want to help. ...

2026-10-27T16:31:38Z

Seeing so many security incidents last week made me want to help. I made a small start by adding basic vulnerability checks to Scala Steward. It only shows what an update fixes for now - no cooldown or schedule settings yet. Feedback and reviews are very welcome!

https://github.com/scala-steward-org/scala-steward/pull/4037

Some #Scala developers have moved to #Rust 🦀, and there are ...

2026-10-27T10:03:11Z

Some #Scala developers have moved to #Rust 🦀, and there are plenty of articles and videos about this transition. But this one is the opposite - a Rust developer moved to Scala! 👇

https://watch.softinio.com/w/p/1y91HpAp7Nd3WcuAKXpGLz

Long CI times are a common headache, and let's be honest, ...

2026-10-24T19:32:48Z

Long CI times are a common headache, and let's be honest, tweaking pipelines is tedious. 😏 Almost every team has this task buried in their backlog. With AI agents, it's finally time to fix it. Bring this up at your next team meeting!

https://alexitc.com/blog/2026-10-23-from-27-minutes-to-4-cutting-ci-build-time-by-85-percent/

🚨 Everyone is talking about hacked #PHP, but the #JVM is also ...

2026-10-23T06:36:00Z

🚨 Everyone is talking about hacked #PHP, but the #JVM is also affected by the latest avalanche of vulnerabilities. Read this article and download the audit script ASAP 👇

https://www.scala-lang.org/blog/jdk-certificate-vulnerability.html

A quick cheat sheet on Scala 3 capture checking - straight to the ...

2026-10-22T17:38:27Z

A quick cheat sheet on Scala 3 capture checking - straight to the code examples with zero fluff 👇

https://blog.rhetoricalmusings.com/posts/capture-checking/

A very interesting project powered by kyo! ✨ tui4s is a ...

2026-10-22T09:10:13Z

A very interesting project powered by kyo! ✨

tui4s is a terminal UI runner for #Scala 3. It uses kyo-ui to handle cell layouts, reactive signals, and keyboard events, and it can even share UI code between the terminal and the browser.

👉 https://tui4s.yuri4n.dev/

Scala rewritten in Rust before GTA 6 🤯 Well, at least a ...

2026-10-21T06:19:35Z

Scala rewritten in Rust before GTA 6 🤯

Well, at least a scripting subset. Scivolo ports the Scala 3 frontend to Rust to run scripts without a JVM or compile server. The goal is simple: make Scala scripts start as fast as Python while keeping static types.

https://github.com/reactivecore/scivolo

"Errors in production are expensive. Downtime costs real ...

2026-10-19T06:19:08Z

"Errors in production are expensive. Downtime costs real money."

Gordon Cooke learned this the hard way. His team rewrote a Scala service into Java, hoping for lower costs, easier hiring, and faster time to market. It completely backfired into far more bugs, a bigger team, and higher maintenance bills.

Paying a talent premium up front is just buying insurance against broken software.

https://youtu.be/lC1XP5tG0WE

Improving performance is another pillar to keep #Scala relevant ...

2026-10-16T14:01:59Z

Improving performance is another pillar to keep #Scala relevant in the #AI era. Alongside bulletproof types, we need code that runs fast! ⚡

New compile-time specialization in Scala 3 drops #JVM boxing overhead for primitives while staying fully compatible with generic code. You get the speed of raw data with the elegance of generics.

https://youtu.be/xbtoso_F5-Q

My favorite talk from Scala Days 2026 was about baking refinement ...

2026-10-15T20:00:47Z

My favorite talk from Scala Days 2026 was about baking refinement types right into the compiler.

Unlike libraries like Iron or Refined, it adds a built-in solver that verifies logic and math across multiple variables at compile time with zero runtime cost.

Moving from simple checks to full verification is how Scala's type system should evolve to constrain LLMs - AI code won't compile unless the math holds up.

https://youtu.be/rz1BSf_tT58

Even though Scala is niche, I still think it's the most ...

2026-10-14T08:18:51Z

Even though Scala is niche, I still think it's the most AI-ready language. Martin Odersky's Scala Days keynote shows why 👇
https://www.youtube.com/watch?v=jlJyuJhDnlc

Scala 3.10 is here 🎉 This release cleans up legacy syntax, ...

2026-10-12T12:34:38Z

Scala 3.10 is here 🎉

This release cleans up legacy syntax, stabilizes strict equality pattern matching, and brings several new previews and experimentals.

Here are the key highlights:

- `with` type operator is now an error
- Java records pattern matching support
- `//> using dep` now works in the REPL
- Preview: referenceable package objects, relaxed lambdas, and unroll default args
- Experimental: inline traits and agentic spec strings

I already played with relaxed lambdas. I will look into the other new features once I get back from Scala Days. 🙌

Did you know that some parts of Deezer runs on Scala? Read how ...

2026-10-09T07:37:44Z

Did you know that some parts of Deezer runs on Scala? Read how they reduced the size of search cache by 74%! Spoiler alert - by changing the serialization format of the payloads.

https://medium.com/deezer-engineering/how-we-slashed-the-size-of-our-search-cache-by-74-4e2bd5fd65e0

There is something satisfying about internal cleanup and ...

2026-10-08T15:40:23Z

There is something satisfying about internal cleanup and modernization. And that is the case with the newest release of Scala CLI: now built on Scala 3 Next, ready for JDK 24+, and shipping with a smarter fix command plus a fresh docs site.

https://github.com/VirtusLab/scala-cli/releases/tag/v1.18.0

Today, on Thursday, the Scala meetup in Prague with the Typelevel ...

2026-10-08T05:32:20Z

Today, on Thursday, the Scala meetup in Prague with the Typelevel representative is happening! If you are not from Czechia 🇨🇿, check out this list of other events. October should be renamed to Scalober this year 😀

https://www.scala-lang.org/blog/2026/10/06/lets-meet-in-october.html

So the new optional/error type T?E was approved for initial ...

2026-10-07T08:29:22Z

So the new optional/error type T?E was approved for initial implementation. There were times when other languages copied #Scala, but recent direction feels like it is going the other way around. Instead of improving and unifying what we have, we introduce more and more fragmentation.

There are already several libraries across the Scala ecosystem ...

2026-10-05T07:26:47Z

There are already several libraries across the Scala ecosystem integrating Jev, the decision-making model from Typesafe AI. This one is kind of effect-agnostic, based only on sttp abstractions. 👇

https://github.com/ticofab/scala-jev-sdk