Matej Cerny
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matejcerny.bsky.social
Matej Cerny
@matejcerny.bsky.social
Functional programming enthusiast with strong foundations in the relational databases world #FP #Scala #Postgres
Anyone who has ever implemented AWS request signing manually will be pleased to know there is an http4s module for it 👇 #scala
github.com/maginepro/ht...
GitHub - maginepro/http4s-aws: Signed AWS API requests for http4s :lock:
Signed AWS API requests for http4s :lock:. Contribute to maginepro/http4s-aws development by creating an account on GitHub.
github.com
January 2, 2026 at 2:42 PM
Another year of new habits and milestones. Here are the highlights that stand out:

1️⃣ Started a new chapter working for SiriusXM 📻
2️⃣ Continued sharing my passion for tech, (re)posting over 400 articles, videos and tips 💡
December 31, 2025 at 3:10 PM
Another effect system? 🙄 I usually avoid sharing these because I hate fragmentation and this one is still experimental. However, λÆS deserves a look. It implements a unique direct style approach, and the progress is impressive. 🚀 (Also, there is a cats-effect integration!) #scala
December 30, 2025 at 4:37 PM
Super important video on how the CPU actually handles threads and memory access, and why it matters for your app's performance. Watch this to see how cats-effect outperforms standard Spring architecture 👇 #scala #java
www.youtube.com/watch?v=WcJ_...
Antonio Jimenez: Exploring Cats Effect’s New Integrated I/O Runtime [Scala Days 2025]
www.youtube.com
December 30, 2025 at 8:45 AM
In Czech, Chanterelle 🍄 is called "the fox". 🦊 In Scala 3, it means easy named tuple manipulation. A handy utility library from the author of ducktape. #scala github.com/arainko/chan...
GitHub - arainko/chanterelle: chanterelle is a library that provides a map-like DSL over named tuples. Scala 3 only. Some chanterelles are scaly.
chanterelle is a library that provides a map-like DSL over named tuples. Scala 3 only. Some chanterelles are scaly. - arainko/chanterelle
github.com
December 29, 2025 at 10:02 PM
Watch how to use opaque types in some more advanced situations (like hiding Monad Transformers in a DSL) 🤸 #scala
www.youtube.com/watch?v=4PJF...
The hidden power of Scala's Opaque Types
www.youtube.com
December 29, 2025 at 12:42 PM
This is HUGE! 🎉 You can now use your own LLM keys in IntelliJ without needing to pay a separate subscription for Junie! No more clunky Claude beta plugins! Trying it right now and it works like a charm! 🤩 #claude #llm blog.jetbrains.com/ai/2025/12/b...
Bring Your Own Key (BYOK) Is Now Live in JetBrains IDEs | The JetBrains AI Blog
Bring Your Own Key (BYOK) is now available in the AI chat inside JetBrains IDEs as well as for AI agents, including JetBrains’ Junie and Claude Agent. Whether you’re looking to use cutting-edge fronti
blog.jetbrains.com
December 19, 2025 at 3:43 PM
Another prominent Scala developer is taking an interest in Rust. Whether you're a Scala developer expanding your stack or a Rust developer curious about Scala, this tutorial is a great start, even if it's only the first chapter so far. #scala #rust rossabaker.com/blog/rust-bo...
December 19, 2025 at 7:50 AM
Finally, a true dedicated Scala IDE! 🚀

(Just kidding, I swapped the IntelliJ icon 😀) #scala
December 17, 2025 at 1:25 PM
Walkthrough and initial impressions of the Krop framework for Scala 3 from Jakub Kozłowski. #scala
youtu.be/lY88Z1JnUpI
Make delightful web apps with Scala and Krop!
youtu.be
December 16, 2025 at 6:22 PM
A very well thought-out video! The thing is, most Scala influencers are seniors who use effect systems, so expecting them to market simple libraries is unrealistic, at least. #scala www.youtube.com/watch?v=o9wJ...
A New Scala Ethos - Scala Days 2025 talk by Daniel Ciocîrlan
www.youtube.com
December 16, 2025 at 2:17 PM
With Mill moving to YAML, what do you think about sbt's configuration in HOCON? #scala
December 15, 2025 at 11:20 AM
A perfect guide for writing more expressive, efficient code in languages which do not support laziness natively. #scala #javascript #swift matt.might.net/articles/imp...
Understand and implement laziness with examples in Scala, JavaScript, Swift and Racket
matt.might.net
December 15, 2025 at 8:46 AM
For those who are stuck on Scala 2.12, there is a new patch version supporting JDK 25 and 26. #scala
github.com/scala/scala/...
Release Scala 2.12.21 · scala/scala · GitHub
The Scala team at Akka is pleased to announce Scala 2.12.21. This release is compatible with JDK 25 LTS and also introduces preliminary support for JDK 26. The following are highlights of this rele...
github.com
December 12, 2025 at 7:22 AM
It would be so cool if @github.com integrated the releases section right into the main menu! 🔥
December 11, 2025 at 4:33 PM
When I look at what Tomasz is doing, it’s clear that Scala tooling needs more people like him! #scala youtu.be/y18_oHTi53g
Tomasz Godzik: Unleashing the Full Potential of Metals [Scala Days 2025]
youtu.be
December 11, 2025 at 11:24 AM
This is a huge day for the entire Rust community! Congratulations 👏 #rust lwn.net/Articles/104...
The (successful) end of the kernel Rust experiment [LWN.net]
The topic of the Rust experiment was just discussed at the annual Maintainers Summit. The cons [...]
lwn.net
December 10, 2025 at 7:36 PM
"Where Jira meets the command line", do I need to say more? Well, unfortunately, I was not able to connect it with our on-prem Jira server 🥹 jiratui.sh #jira
December 9, 2025 at 7:25 PM
This is what, at least the third version in a row where IntelliJ supports features from the upcoming Scala version before it's even released? Awesome job! 🙌 #scala
blog.jetbrains.com/scala/2025/1...
IntelliJ Scala Plugin 2025.3 Is Out! | The IntelliJ Scala Plugin Blog
Scala Plugin 2025.3 is out! - Support for Scala 3.8 - Better support for macros and export aliases, extension methods, and type lambdas - Structural Search and Replace
blog.jetbrains.com
December 8, 2025 at 9:39 PM
I have a confession to make. In my entire career, I think I’ve explicitly used Coursier exactly once. And that was only to get the Metals integration working with Zed. #scala
December 4, 2025 at 7:47 PM
You all saw the ad for the Brilliant app, right? It's on almost every tech video. But did you know that it's built with Elm? Great talk from Evan Czaplicki covering several strategies on how to grow more functional programmers 🌳 #elm youtu.be/9OtN4iiFBsQ
Evan Czaplicki: How to Grow More Functional Programmers [Scala Days 2025 Keynote]
youtu.be
December 2, 2025 at 8:09 PM
It's Advent of Code time again. 🎄 If you haven't tried Scala yet, this is the perfect opportunity. But don't take my word for it, check out what these three random guys on the internet have to say. 🤣 👇 #scala #AdventOfCode
December 1, 2025 at 8:15 AM
Those tools the guys are talking about are honestly awesome. In short, when you want to communicate with another service, you simply add a contract to the central registry. #scala youtu.be/5bUuGhSmrIU
Are You Tall Enough for This Ride? Real world Challenges in Code Generation [Scala Days 2025]
YouTube video by Scala Days Conferences
youtu.be
November 30, 2025 at 9:31 AM
Pattern matching on interpolated strings is powerful, but can be a bit cryptic. In such cases, I still prefer .contains #scala
November 27, 2025 at 7:47 PM