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August 1st, 2025, ISSUE 594

READING

Golden Literal Testing in uTest 0.9.0

uTest is a small unit testing library I maintain that aims for simplicity and convenience. This blog post explores the Golden testing feature newly-added in uTest 0.9.0: why it is necessary, what it does, and how it works internally. This feature was inspired by the Jane Street blog post "What if writing tests was a joyful experience".
Li Haoyi (@li_haoyi)

VIDEOS

Nussknacker integration with Functional Programming

I'll present how we leveraged functional programming principles while building Nussknacker - low-code visual tool baked in Poland for domain experts to build, run and monitor real-time decision algorithms instead of implementing them in the code.
Piotr Rudnicki
Type-safe vibe-coding a CRUD application

Given a CRUD application template (or better, let's call it a microservice template), how will an LLM fare adding a fridge-content-management feature? Will it be able to follow the patterns laid out in the app? Starring: Cursor IDE, Claude 4 Sonnet, Bootzooka template, JVM 21, Virtual Threads, blocking direct-style programming, Scala+Tapir on the backend, TypeScript+React on the frontend. Bonus: see the Scala Metals and context7 MCPs servers in action, accompanied by instant compiler feedback - which really helps out the LLM during development!
Adam Warski (@adamwarski)

RELEASES

Metals 1.6.1

SQL highlighting, Model Context Protocol improvements, updates to fuzzy matcher logic, new X-ray inlay hints, and more!
Metals contributors

EVENTS

LLM4s Dev Hour – Sundays @ 9am London Time

Just finished another great hour of mob programming. We’re now doing this every Sunday — 60 minutes of live coding, debugging, and learning together in public.
LLM4s
Scala Days, Aug 19th - 21st, Lausanne, Switzerland

Leaders from Scala User Groups and global communities, students, and language contributors will gather to discuss academic research, use cases, and visionary projects for a two-day, action-packed event.
Scala Days (@scaladays)
The Scala Workshop, Oct 13th, Singapore

The Scala Workshop is the continuation of the Scala Symposium, providing a forum for researchers and practitioners to discuss the design, implementation, and applications of the Scala programming language. Topics include language features, compiler internals, type systems, libraries, tools, and industrial applications.
EPFL
DEVJVM, Oct 25th, Barranquilla, Colombia

A conference uniting Java, Kotlin, and Scala developers.
DEVJVM





  1. Scala Times Issue #594

    Golden Literal Testing in uTest 0.9.0. Nussknacker integration with Functional Programming. Type-safe vibe-coding a CRUD application. LLM4s Dev Hour – Sundays @ 9am London Time. Scala Days, Aug 19th - 21st, Lausanne, Switzerland.


  2. Scala Times Issue #593

    Understanding Scala Variance. LLM4s Dev Hour – Sundays @ 9am London Time. Scala Days, Aug 19th - 21st, Lausanne, Switzerland. The Scala Workshop, Oct 13th, Singapore. DEVJVM, Oct 25th, Barranquilla, Colombia.


  3. Scala Times Issue #592

    LLM4s Dev Hour – Sundays @ 9am London Time. Scala Days, Aug 19th - 21st, Lausanne, Switzerland. The Scala Workshop, Oct 13th, Singapore. DEVJVM, Oct 25th, Barranquilla, Colombia.


  4. Scala Times Issue #591

    Scala Days, Aug 19th - 21st, Lausanne, Switzerland. The Scala Workshop, Oct 13th, Singapore. DEVJVM, Oct 25th, Barranquilla, Colombia. Mill Build Tool v1.0.0 Release Highlights. Business4s H1 2025 Highlights.


  5. Scala Times Issue #590

    Scalator: Stream Composition with Kyo & Community Revival!, Jul 9th, Toronto. Scala Days, Aug 19th - 21st, Lausanne, Switzerland. The Scala Workshop, Oct 13th, Singapore. CFP for DEVJVM, Oct 25th, Barranquilla, Colombia. Anatomy of a Scala Game Server.


  6. Scala Times Issue #589

    Scala Highlights, June 2025 edition. ScalaWAW #35 - Summer hackathon, Jun 30th, Warsaw, Poland. Scala Days, Aug 19th - 21st, Lausanne, Switzerland. The Scala Workshop, Oct 13th, Singapore. Making Capabilities Safe and Convenient.


  7. Scala Times Issue #588

    Fundamental Concurrency Problems and Solutions. Scala Days, Aug 19th - 21st, Lausanne, Switzerland. The Scala Workshop, Oct 13th, Singapore. S2D migrated to Scala Native.


  8. Scala Times Issue #587

    First Make It Correct. Suspension: the magic behind composability (or: "The Kyo Monad"). My experience migrating a PlayFramework app to Scala 3. Yet Another Scala 3 Migration Story. The Elements of Kyo.


  9. Scala Times Issue #586

    Making ScalaSql boring again (with interesting new internals). Lambda World proposal online hack, Jun 12th, Online Event. 10% discount for Lambda Days, June 12th-13th, Kraków, Poland. Scala Days, Aug 19th - 21st, Lausanne, Switzerland. The Scala Workshop, Oct 13th, Singapore.


  10. Scala Times Issue #585

    IntelliJ IDEA x Scala: How to clone carets. Scala Days 2025 - Functional Programming And The Real World. Developer Ecosystem Survey 2025. ScalaWAW #34, May 26th, Warsaw. Scala Hamburg: Recursion Schemes & Mill, Jun 2nd, Hamburg, Germany.


  11. Scala Times Issue #584

    Scala 3 migration Tips and Tricks. Learn Scala with Alvin Alexander . A Distributed System from scratch, with Scala 3 - Part 3. Can we ScalaSQL on Duckdb?. Unison, from a Scala perspective.


  12. Scala Times Issue #583

    Workflows4s Finally Released - You Might Hate Your Business Processes a Little Less. Business4s & GSoC 2025: 3 Exciting Projects and Not-So-Usual Approach. Unison, Scala, Distributed Systems and Delightful Programming. ScalaWAW #34 May 26th, Warsaw. Scala Hamburg: Recursion Schemes & Mill, Jun 2nd, Hamburg, Germany.


  13. Scala Times Issue #582

    How Scala Ruined My Java (in a good way). IntelliJ IDEA x Scala: Named Tuples. Random Scala Tip #624: The Pitfalls of Option Blindness. From JavaScript to Scala. Scala 3: The Evolution of a Macro.


  14. Scala Times Issue #581

    WORKSHOP: Principled Metaprogramming in Scala 3. The Scala Workshop 2025 - The Scala Workshop 2025. Programming a Language by Nicolas Rinaudo | Scalar Conference 2025.


  15. Scala Times Issue #580

    On vibe coding. Composing Independent Instruction Sets with Free Monads in Scala 3. Announcing Scala.js 1.19.0. Tagless Final for Humans by Noel Welsh | Scalar Conference 2025. Release v1.0.0-RC19 · zio/zio-dynamodb · GitHub.


  16. Scala Times Issue #579

    Scalar Conference 2025 - Summary & Highlights. Experimental Capture Checking: New Syntax for Explicit Capture Polymorphism. Whiteboxish Macro Powers with Named Tuples. IntelliJ Scala Plugin 2025.1 Is Out!. J On the Beach, May 14th - 16th, Málaga, Spain.


  17. Scala Times Issue #578

    Sttp client 4: the Scala HTTP client you always wanted, released!. London Scala User Group Meetup, Apr 16th, London. J On the Beach, May 14th - 16th, Málaga, Spain. 10% discount for Lambda Days, June 12th-13th, Kraków, Poland. Scala Days 2025 CFP, Aug 19th - 21st, Lausanne, Switzerland.


  18. Scala Times Issue #577

    Tagged vs Untagged Unions (in Scala). -XX:+UseCompactObjectHeaders is your new TURBO button for JDK 24+ . Scala Days proposal online hack, Apr 3rd, 8PM CEST, online event. London Scala User Group Meetup, Apr 16th, London. J On the Beach, May 14th - 16th, Málaga, Spain.


  19. Scala Times Issue #576

    API First Scala. Strategies for Efficiently Parallelizing JVM Test Suites. Publishing ZIP artifacts with SBT. London Scala User Group Meetup, Apr 16th, London. J On the Beach, May 14th - 16th, Málaga, Spain.


  20. Scala Times Issue #575

    Data Plumber - Data Integration Pipeline. 15% discount for Scalar, Mar 27th - 28th, Warsaw, Poland. London Scala User Group Meetup, Apr 16th, London. J On the Beach, May 14th - 16th, Málaga, Spain. CFP for Lambda Days, June 12th-13th, Kraków, Poland.


  21. Scala Times Issue #574

    Debugging session #2: Scala 3 lazy vals & serialization. Infrastructure as types: introducing TypeOps. 15% discount for Scalar, Mar 27th - 28th, Warsaw, Poland. London Scala User Group Meetup, Apr 16th, London. J On the Beach, May 14th - 16th, Málaga, Spain.


  22. Scala Times Issue #573

    GSOC 2025: Call for contributors. Drawing Heighway’s Dragon - Recursive Function Rewrite. From Python to Scala: Rewriting 27k Lines of a CLI. Spotify FOSS Fund 2024. Functional World #16, Mar 11th, Online Event.


  23. Scala Times Issue #572

    Rock the JVM partners with the Scala Center. Typelevel Summer of Code 2025. Functional World #16, Mar 11th, Online Event. 15% discount for Scalar, Mar 27th - 28th, Warsaw, Poland. London Scala User Group Meetup, Apr 16th, London.


  24. Scala Times Issue #572

    Fast Incremental JVM Assembly Jar Creation with Mill. Calling Scala Native from Java using FFM. Announcing Scala Days 2025, Aug 19th - 21st, Lausanne, Switzerland. Scala In The City, Feb 25th, Hamburg, Germany. Scala in the City, Feb 26th, Berlin, Germany.


  25. Scala Times Issue #571

    Fast Incremental JVM Assembly Jar Creation with Mill. Calling Scala Native from Java using FFM. Announcing Scala Days 2025, Aug 19th - 21st, Lausanne, Switzerland. Scala In The City, Feb 25th, Hamburg, Germany. Scala in the City, Feb 26th, Berlin, Germany.


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