Hello everybody, I'd like to let you know about a recent experiment/POC I've been working on recently:

Safe Scala is a recent experimental feature. In short, it is a subset of Scala which doesn't allow for any sideffects. Any sideeffecting tools, especially Java standard library are just not aceesible -- a program using those won't compile. Thus the only way to peform side effects is via explicitly passed in Capabilities. That may sound like a pure academic excercise.

But there is a project called Dapr which is aiming to abstract cloud applications from the hassle of I/O (queues, sync messaging, distributed locks, state, durable workflows, etc.). Thus allowing apps to focus on business logic and use dapr as a framework (running out of the app process). What if we could represent these capabilities of Dapr as Scala Capabilities?

That's exactly what dapr4s does. It uses Dapr's Java SDK behing the scenes but exposes a pure Capability-style Scala facade. It is still just an experimental project, nothing ready for production (at least just yet). But it's a POC -- a proof that Safe Scala can be practical to build (maybe even line of business boring) cloud apps.

Here's the link to the project:

https://github.com/sideeffffect/dapr4s

Repository with examples and a slides with more info:

• https://github.com/sideeffffect/dapr4s-examples
• https://github.com/sideeffffect/dapr4s-examples/blob/master/SLIDES.md

I hope you'll find this project inspiring and would be happy to discuss details at Scala Days 2026 in Berlin.

(Disclosure: the project has been developed with the help of LLMs.)

🚀 Introducing Scala Packages: https://pkg.scalanews.net

A fast, modern search for Scala libraries:

🔍 Every Scala library on Maven Central: JVM, Scala.js, Scala Native, and sbt & Mill plugins 🆕 New projects and new releases on the home page, plus an Atom feed 🧩 Free JSON API, no key needed 🤖 MCP server, so AI assistants can search packages and fetch install snippets: claude mcp add --transport http scalapkg https://pkg.scalanews.net/mcp

It complements Scala News (https://www.scalanews.net): the newsletter for what the community is writing, and Scala Packages for what it's releasing.

If you're still on Scala 2 and were worried that it might stop being maintained, worry not! Of course, if you need help migrating to Scala 3 we are even more happy to help.

Hi all, we at Deezer work a lot with Scala and today I published a blog post about some fun things we've done with it.

TLDR; the search at Deezer was clogging up our cache systems. We significantly improved the situation by changing the serialization format of the cached payloads, and rolling out a tailor-made, space-efficient and blazing fast data structure inspired by Hash Array Mapped Tries.

I'm currently working on a project looking at how/why devs and CTOs choose programming languages, and I'm particularly interested in understanding people's experiences with Clojure.

The survey takes about 7 mins, and I'd love to hear from as many people as possible!

Appreciate it 🙌

Here's the survey

This issue of Scala Times is all events, no articles - everything happening over the next few weeks in one place:

https://scalatimes.com/be439e050d

• Tech walk through Berlin, Oct 11
• Scala Days, Oct 12–13, Berlin
• Func Prog Conf, Oct 14, Stockholm
• Scala Summit, Oct 19, San Francisco
• Chicago Scala Meetup (Scala + AI, guest talk by Daniel Spiewak), Oct 22
• New York Scala Meetup (Scala + AI), Oct 26
• J On The Beach, Oct 29–30, Málaga
• Lambda World, Oct 29–30, Málaga

The Chicago and NYC meetups are part of a VirtusLab US tour right after Scala Days. If you're nearby, come say hi!

Organising something we missed? You can submit it at [scalatimes@softwaremill.com](mailto:scalatimes@softwaremill.com)

Join us at the Scala Hangout this Thursday (Oct 8) at 6pm CT.

LoopMe (AI adtech, London HQ, 400+ people) is hiring a Scala engineer in Kraków 🚀
You'd work on our SSP, Adserver and Exchange: real-time auctions, sub-200ms globally, all built in-house.

Stack: Scala, Java, Kafka/PubSub, MongoDB/Bigtable GCP/AWS (Python is a plus)
Salary: up to 30k PLN B2B
Perks: hybrid work, 1 month work-from-anywhere, 8% annual bonus, Multikafeteria.

Details: https://apply.workable.com/loopme/j/FB3E61C660

Title:

Hi r/scala! I'm building marola, an open-source app that ranks nearby beaches by sea conditions, weather and official water-quality reports. The swim score and safety rules are plain, tested Scala 3 with Kyo. There's no national view of beach water quality in Brazil today, because each state publishes its own reports. marola reads three states so far, and the goal is to build that national view.

Live map (Florianópolis, Rio, Salvador): https://marola.dev
Repo (MIT): https://github.com/marola-dev/marola

I'd love feedback, especially from people who've used Kyo, and contributors are welcome.

Play Framework 2.9.12 and 3.0.12 just got released - upgrading Netty to fix many CVEs, fixing a bug in the reverse router and improving Scala 3 support in routes files! 🚀

• Play 2.9.12
• Play 3.0.12

Framework development and social media are an interesting combination.

You spend months working on architecture, rendering, APIs, SSR, hydration, modularization, security, and all the small decisions that eventually make up a framework.

And then you try to talk about it on social media.

The first problem: spam filters.

You can write a completely legitimate technical post, but the moment you include a link to the project, it can suddenly look like advertising. Some platforms reduce its visibility, others remove it, and sometimes it simply disappears into a spam folder.

The second problem is probably even harder:

The concepts themselves are barely noticed anymore.

You can explain why an architecture is designed a certain way, what problem it solves, or why you deliberately chose a different approach from established frameworks.

But often, that is not what people discuss.

Instead, one sentence from the documentation, one headline, or one small API detail gets picked apart.

And suddenly everyone is discussing a tiny detail while the actual concept is completely ignored.

That leads directly to the third problem:

The surface gets judged more than the idea behind it.

One questionable term, one awkward sentence, one reference in the wrong place and that can generate twenty comments.

The architecture underneath it?

Maybe none.

And now there is a fourth layer:

“AI slop.”

As soon as someone notices or suspects that AI was involved in documentation, code, text, or design, sometimes the result itself is no longer evaluated.

The discussion suddenly stops being:

“Is this concept good?”

and becomes:

“This was made with AI.”

For me, AI is a tool.

I develop the concepts, make the architectural decisions, have things implemented, review them, throw parts away, rebuild them, and test the result.

But that also makes one thing very clear:

Good review matters more than ever.

AI can produce a huge amount of work very quickly.

But speed does not replace technical responsibility.

Maybe that is one of the real challenges for framework developers today:

Not only building good technology.

But somehow getting people, between spam filters, short attention spans, detail discussions, and “AI slop” comments, to stop for a moment and ask:

“Okay, but what is the actual idea behind this?”

 https://github.com/anjunar/scalajs-ui

Updated dotty-cps-async - switched to 3.9.x LTS. For Scala 3.3.x, use the 1.3. x series; it will be supported sometime.

User-visible changes: support for named patterns (introduced in Scala 3.6), which can be useful for people who write code by hand.

Full release notes: https://github.com/dotty-cps-async/dotty-cps-async/releases/tag/1.4.0

Kyo v1.0.0-RC7 ships a new kernel and a large body of stabilization work on the way to 1.0. Resource release is now structural: a release runs however its region exits, including on interrupt. Ten issues close with it, and a trailing map chain goes from 507,800 to 560 us/op 🚀

Highlights:

• kyo-sql: embedded SQLite behind the same API as PostgreSQL and MySQL, every engine passing one conformance battery, and Dolt backends, a version-controlled SQL database whose tables branch, commit, diff, and merge, so an AI agent can work on a branch of real data and merge or discard it.
• kyo-system: file access on JVM, JS, Native, and Wasm from one module, plus processes and environment, with positioned channels, interrupt-safe locks, watching, and a virtualizable file system.
• kyo-system-doltfs: a file system stored in Dolt, so ordinary Path code runs unchanged on a directory tree that branches, commits, diffs, and merges, and that answers SQL: an agent can edit files on a branch, and the change is reviewed as a diff and merged or discarded.
• kyo-ai: typed decisions with calibrated probabilities through TypeSafe AI's Jev, and agents that call any MCP server's tools with no Scala types.
• Scala.js: effect dispatch 10x to 18x faster.
• Time control: Clock.withTimeOffset moves the wall clock alone, joining withTimeShift, which scales the rate of time and sleeps with it, and withTimeControl, which drives virtual time by hand.
• Stabilization: kyo-flow's durable execution rebuilt for crash recovery, with every write fenced by the executor's claim, interrupt-safe SQL sessions, and leak-free transport teardown.

Kyo now builds on Scala 3.9.0, so a project depending on the main modules needs 3.9 too. The scheduler, kyo-config, and kyo-stats-registry stay on 3.3.8 and 2.13.

Full release notes, including the breaking changes: https://github.com/getkyo/kyo/releases/tag/v1.0.0-RC7

📰 New Scala News is out: the August 31, 2026 edition, with dependent types, sbt plugin classpath isolation, an sbt security fix and more.

The site's had a refresh too!