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April 3rd, 2025, ISSUE 577

READING

Tagged vs Untagged Unions (in Scala)

What’s the difference between Option[A] and A | Null? How about between Either[A, B] and A | B?
Alexandru Nedelcu (@alexelcu)
-XX:+UseCompactObjectHeaders is your new TURBO button for JDK 24+

Compact Object Headers reduce the memory overhead of each object, leading to less pressure on memory allocation and potentially better cache utilization. For memory-intensive tasks like JSON processing, this can translate directly into higher throughput.
Andriy Plokhotnyuk (@aplokhotnyuk)

EVENTS

Scala Days proposal online hack, Apr 3rd, 8PM CEST, online event

Are you interested in speaking at Scala Days, but not sure what to speak about? Join the Scala Days proposal hack! Come and discuss ideas in a friendly and welcoming environment.
Zainab Ali (@_zainabali_)
London Scala User Group Meetup, Apr 16th, London

Solving Scala's Build Problem with Mill & Mystery talk.
London Scala User Group (@londonscala)
J On the Beach, May 14th - 16th, Málaga, Spain

Use special promo code Sc4l4OTB for Scala Times readers to get 10% discount!
J On The Beach
15% discount for LambdaConf, May 10th - 16th, Estes Park, CO, USA

This year's conference will feature a hand-picked lineup of renowned and new speakers, thought-provoking keynotes, hands-on workshops, hackathons, and panel discussions. Whether you are a seasoned professional or just starting your journey in functional programming and AI, LambdaConf 2025 offers something for everyone.
LambdaConf (@lambda_conf)
10% discount for Lambda Days, June 12th-13th, Kraków, Poland

Our event is one of the biggest functional programming conferences in Europe with 2 days packed with inspiring talks, networking opportunities, and, of course, some fun(). Use promo code Time4Scala for a special discount for our readers!
LambdaDays (@LambdaDays)
Scala Days 2025 CFP, Aug 19th - 21st, Lausanne, Switzerland

Submit your talk to be part of Scala Days 2025! The Call for Proposals is officially open and will close on April 6th, 2025, at 11:30 pm GMT.
Scala Center (@scala_lang)

VIDEOS

Effect Oriented Programming, Writing Code in the Age of AI, Curiosity and Exploration

A long conversation between Daniel Ciocîrlan (RockTheJVM) and James Ward.
James Ward (@_JamesWard)

RELEASES

commoncrawl-stream

This project demonstrates how to process data fetched from CommonCrawl with Spark NLP & Tika.
Ivan Potapov
Kyo 0.17.0

This is likely one of the last releases before the 1.0-RC cycle! Please report any issues or difficulties with the library so we can address them before committing to a stable API.
Kyo contributors
mill 0.12.10

A bunch of fixes and improvements.
Mill contributors
cdxgen 11.2.x

cdxgen can generate a variety of Bill of Materials (xBOM) for a number of languages, package managers, container images, and operating systems. With the latest release v11.2.x, we have added a hybrid (source + TASTy) semantic analyzer for Scala 3, to improve the precision and richness of information in the generated CycloneDX SBOM.
cdxgen contributors
tasks

Task datatype, meant for cross-language interop (Java, Kotlin, Scala),
Alexandru Nedelcu (@alexelcu)

VARIA

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