Rock the JVM @rockthejvm Twitter profile

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Rock the JVM

1 month

🚨 New course: Kotlin Coroutines and Concurrency 🚨 Come write 2000 lines of code with me and learn the ins and outs of concurrency with #Kotlin : Read more for details and deals 👇 So who is it for? This course is for Kotlin developers who need to

Kotlin Coroutines and Concurrency

Learn everything about Kotlin Coroutines and become a master of concurrency in Kotlin in this advanced hands-on course.

rockthejvm.com

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Rock the JVM

@rockthejvm

2 years

Which companies are using #Scala ? Here's a starting list for you: LinkedIn Twitter Apple Adobe Netflix Airbnb Verizon Spotify Disney Streaming Databricks Microsoft - yes, trained a team there Here Maps Intuit Samsung Tesla Stripe Zalando Uber LEGO - yes, that LEGO

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@rockthejvm

2 years

Backwards: - The technical merit of #Scala is _the_ reason why Twitter works well as a distributed system - Scala is older than Go, and Twitter is not the only example in its track record "Hipster language"? Try your first 100 lines, you'll love it

Amjad Masad

@amasad

2 years

Twitter should rewrite the Scala parts in something with a proven track record like Golang and definitely don’t get tempted to try another hipster language. Language success is impossible to predict and can’t be chosen merely on technical merit (they’re social constructs)

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Rock the JVM

@rockthejvm

3 years

Just finished a live 2-day #Scala training session with Microsoft (!). Apparently they needed it for Spark. They had no idea what Scala is capable of. Left the training blown away.

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@rockthejvm

9 months

Scala

Christopher Ehrlich

@ccccjjjjeeee

9 months

Which technology is this?

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@rockthejvm

2 years

Folks, get your act together. This was #Scala 15 years ago. Scala needs some more serious marketing.

Gavin Ray

@GavinRayDev

2 years

@BrianGoetz Genuine snippet of code from today -- if you'd have told me that this was Java, 5 years ago, I'd have told you to stop taking the piss. Just brilliant, I'm in awe.

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@rockthejvm

1 year

Play Framework is back in business! After 4 years with no major release, it's about to ship 2.9.0 with support for the latest JDK and #Scala 3, then will release 3.0 soon after, with Pekko replacing Akka

Play Framework

@playframework

1 year

The Play 2.9.0 Release Candidate is now available! 🎉 We are almost there! Thank you to EVERYONE involved making this happen! 🙏🥳

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Rock the JVM

@rockthejvm

10 months

Learning #Scala will give you foundational, transferrable skills, even if you end up writing something else. Very few languages are this powerful.

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@rockthejvm

11 months

#Scala is still an underrated language, even as other languages copied some of its features over time. It's even more underrated for frontend dev - I'm far more productive with Laminar or Tyrian in ScalaJS than any other JS-native framework.

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Rock the JVM

@rockthejvm

2 years

🚀 IT HAS ARRIVED! 🚀 Introducing... The Typelevel Rite of Passage - a product-based course in #Scala 3 with the Typelevel stack: What we'll build, what to expect and deals - read more 👇

Full Stack Scala Project-Based Course with Typelevel

Learn how to build full-stack Scala 3 applications with the Typelevel stack in this long-form online course.

rockthejvm.com

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@rockthejvm

2 years

A big #Scala project-based course is coming soon

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@rockthejvm

3 years

OMG OMG I'm there in @odersky 's recommendations list!

Seth Tisue

@SethTisue

3 years

if-you’re-new-to-Scala learning materials recommendations from @odersky

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@rockthejvm

2 years

The ZIO 2.0 course is here! 🚀 Master pure functional programming with one of the hottest tools in the #Scala world: What's inside, what to expect and deals - read below 👇

ZIO Course for Scala Developers

Learn ZIO 2.0 in this masterclass for pragmatic functional programming in Scala. An online course for Scala developers.

rockthejvm.com

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@rockthejvm

2 years

#Java #Scala #Kotlin

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@rockthejvm

1 year

The main selling point of #Scala now is effect systems, which don't have an equal in other languages. Powerful, safe, fast, scalable, readable and testable software.

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@rockthejvm

1 year

#Scala is not a "better Java". It's a completely different beast, with huge unused potential.

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@rockthejvm

4 years

Monads are monoids in the category of endofunctors - a #Scala 3 journey, tweet-size, no psychobabble Read on 👇

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@rockthejvm

4 years

Here's a 2021 resolution for all developers: Try #Scala for a day.

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@rockthejvm

3 years

As a celebration to the #Scala 3 launch, here's a thread with all the material I've published so far on Scala 3: 👇

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@rockthejvm

2 years

Finished recording. 35 hours, jam-packed. This course is 3x longer than the biggest Rock the JVM course, and 10x more important.

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@rockthejvm

2 years

Pure functional programming is 100% compatible with blazing-fast performance.

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@rockthejvm

3 years

A language close to what I posted for April Fool's day last year, except it's very real: - Scala-like syntax - first-class ADTs - first-class type classes - pattern matching - higher-kinded types - polymorphic effects - declared purity - runs on the JVM

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Rock the JVM

@rockthejvm

3 years

Scala has many features. Java copies a few. Then Scala brings many new features. Then Java copies a few more. #Scala is the adventurer. #Java is the conservative. One learns from the other. No loser, only winners.

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@rockthejvm

2 years

The difficulty of learning FP comes from everything you have to unlearn.

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@rockthejvm

3 years

Had something more fun to show last week in #Scala , but suddenly nothing was fun anymore. The Ukraine conflict put a pause on Rock the JVM's ongoing work over the last few days. Some updates: 1/

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@rockthejvm

4 years

#Scala is not just "a better Java".

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@rockthejvm

1 year

Make #Scala adoption irresistible by using Atomic Habits: 1. Make it obvious. Show people compelling results built with Scala, so much so that it's impossible not to get their attention. A few years ago, @Akka , @ApacheSpark , @PlayFramework and @Finagle built such powerful

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@rockthejvm

2 years

Reading an imperative program, you need to keep internal state in your mind. Reading a functional program, you only need to keep types in your mind.

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@rockthejvm

1 year

Preparing a new #Scala "black magic" course with the most powerful and esoteric features of the language. Topics include - macros and metaprogramming - type class derivation - type-level programming - advanced type system concepts What else would you like to see?

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@rockthejvm

4 years

#Scala is not just a language. By learning Scala, you learn to think differently.

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Rock the JVM

@rockthejvm

2 years

Achievement of the day: a Rock the JVM student just merged their first (non-trivial) PR in Cats core!

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@rockthejvm

3 years

After learning #Scala , chances are low that you'll go back to anything else. After learning effects, chances are low that you'll go back to regular Scala.

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@rockthejvm

2 years

Learn #Scala because it will help you grow as an engineer. The mental clarity, exciting work and high-paying jobs will come as a byproduct of your new skills.

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@rockthejvm

2 years

Unless @elonmusk retains it, there is now some badass #Scala talent on the market.

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@rockthejvm

3 years

Be kind to folks maintaining OSS.

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@rockthejvm

8 months

New long-form video! How to Write a Full-Stack #Scala application with the Typelevel stack: We'll cover - a database module with Doobie - a server with http4s - code organization on the backend - a small frontend with Tyrian doing a backend call

How to Write Full-Stack Scala Applications - Typelevel

blog post: https://blog.rockthejvm.com/full-stack-typelevelGitHub repo: https://github.com/rockthejvm/full-stack-typelevel-demoFull Stack Scala course with T...

www.youtube.com

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Rock the JVM

@rockthejvm

3 years

Just learned this from one student: In their company, the Rock the JVM #Scala courses are officially part of the onboarding process for team members with no prior experience. After a few days, they're ready to contribute. 💪

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Rock the JVM

@rockthejvm

3 years

Developers will spend $4000 on a new computer because "it makes me more productive and saves me time" ... but then also NOT spend $85 on a course that makes them more productive and saves them time because they'd rather spend 400 hours learning it themselves

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Rock the JVM

@rockthejvm

9 months

#Scala has been doing an amazing job at type systems for 20 years, no “AI” needed

Elon Musk

@elonmusk

9 months

@MarkovMagnifico Done right, a compiler should be able to figure out type automatically. It’s not that hard. Not that it will matter much in the AI future.

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@rockthejvm

2 years

#Scala 's for-comprehensions were designed to be a "hook" for beginners, who first think they're loops. They're not. But what are they? This combinator (as a concept) probably needs its own word.

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@rockthejvm

2 years

After years of hard work, #Kotlin is hitting a sweet spot as a mainstream language.

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@rockthejvm

2 years

Dynamically typed languages only work because you already have the types in your head.

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Rock the JVM

@rockthejvm

3 years

Donated $1000 to the Ukraine Humanitarian Fund, managed by the UN. Rock the JVM is a small (1-person) Romanian 🇷🇴 business. Ukraine 🇺🇦 is our neighbor. 3/

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Rock the JVM

@rockthejvm

3 years

Ending the year with a bang and a new and massive article! The Doobie tutorial in #Scala - how to interact with a database using pure functional programming: cc @petr_zapletal @ScalaTimes cc @tpolecat for feedback

Learn Doobie for the Greater Good

We rely on the JDBC specification if we need to connect to SQL databases in the JVM ecosystem. However, JDBC is not a good fit if we use functional programming since the library performs a lot of...

blog.rockthejvm.com

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Rock the JVM

@rockthejvm

3 years

The Cats Effect 3 course is here! 🚀 Become a badass #Scala engineer with pure functional programming, composable and high-performance code! What's inside, what to expect and launch discounts - read below 👇

Cats Effect Course for Scala Developers

Learn Cats Effect 3 in this online course for Scala developers.

rockthejvm.com

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@rockthejvm

4 years

On covariance and contravariance. Picture source:

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@rockthejvm

3 years

Code review be like: 15 lines - 10 comments, requesting changes 1500 lines - lgtm

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@rockthejvm

2 years

JDK 19 structured concurrency and virtual threads are both proof that #Scala has been doing it right.

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@rockthejvm

2 years

Oh, you want a #TypeScript vs #Scala duel on type-level programming?

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Rock the JVM

@rockthejvm

2 years

Maybe unpopular opinion: FlatMap is the single most important function in FP. Our natural language vocabulary being poor at expressing extremely precise concepts in single words, let this word be flatMap, instead of borrowing words that mean something else.

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Rock the JVM

@rockthejvm

3 years

One day of thanks is not enough. Hats off to @odersky & team. What you've made is not just a tool. #ScalaThankYou

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@rockthejvm

2 years

New blog post! The Ultimate Guide to #Java Virtual Threads: - how to create virtual threads - how virtual threads work - cooperative scheduling - what "good practice" means now with virtual threads - JDK internals - code examples throughout Link:

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@rockthejvm

3 years

One of my students just got their first job, another landed at Apple. It's a good day for my community at Rock the JVM 💪

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@rockthejvm

1 year

The backend of X, the soon-to-be everything app, is written in #Scala .

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@rockthejvm

4 years

Dear Santa, can you please make all developers in the world write 20 lines of #Scala to see if they like it? Thanks.

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Rock the JVM

@rockthejvm

2 years

Recording of the new project-based course in full swing. The project is small, but not a toy; something real. This is not just a course. It's an experience in software dev, felt live. Can't wait to show it to you.

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Rock the JVM

@rockthejvm

1 year

New big tutorial: How to write a Two-Factor Authentication (2FA) system with one-time passwords (OTP) using #Scala and Http4s: by @kateuherbert cc @ScalaTimes @petr_zapletal

Two-Factor Authentication in Scala with Http4s

Learn how to write a two-factor authentication mechanism using one-time passwords (HOTP and TOTP) with Scala and Http4s.

blog.rockthejvm.com

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@rockthejvm

2 years

If Twitter bet on #Scala when it had almost zero adopters and became the powerhouse it is, you can bet on Scala today.

Vladimir Kostюkov

@vkostyukov

2 years

A few takes on how hardcore @TwitterEng has been. Let's talk about @finagle and Scala for a minute.

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@rockthejvm

1 year

Companies say that hiring #Scala developers is hard. Developers say that finding #Scala jobs is hard. Are both true?

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@rockthejvm

3 years

Recently held a company training on #Spark optimization with Python. The first optimization tip: ditch Python, use #Scala .

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@rockthejvm

11 months

How to build a load balancer in #Scala with http4s and Cats Effect in 100 lines of code: - how a load balancer works - how to replicate an app - how to redistribute calls between many replicas - how to return correct responses to users - how to cycle between backends

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@rockthejvm

2 years

JavaScript: ["10", "10", "10", "10"].map(parseInt) = [10, NaN, 2, 3] OMG 🤦‍♂️ this runs the internet?! #Scala , wake up! You shouldn't compile to JavaScript, JavaScript should compile to you! (example from @li_haoyi )

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@rockthejvm

1 year

A big reason why Rock the JVM exists - comments like this: "I started a new job that uses Scala and your videos have helped me tremendously. Thank you"

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@rockthejvm

3 years

Preparation for the #Akka Typed Essentials course is complete. Starting recording on Monday. It's been long overdue.

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@rockthejvm

3 years

New video! Tagless Final in #Scala in a digestible step-by-step tutorial:

Tagless Final in Scala

Written form: https://blog.rockthejvm.com/tagless-final/In this video, we'll demonstrate Tagless Final, one of the design patterns in Scala (and other FP lan...

www.youtube.com

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@rockthejvm

1 year

#Scala needs a punchline. Here's one I use whenever someone asks why they should write Scala: Scala is a super expressive language that allows you to write complex systems quickly and safely. You'll also have a lot of fun doing it!

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@rockthejvm

3 years

Functional programming is in an excellent position to dominate data-intensive applications in the years to come.

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@rockthejvm

2 years

To be clear, this is the _actually_ weird `for` structure in a programming language: for (int i = 0; i < 10; i++) { } It's funny so many of us start with this one, only to unlearn it later

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Rock the JVM

@rockthejvm

10 months

🚀 ZIO Rite of Passage is now live! 🚀 Write a full-stack product in #Scala 3 with the ZIO stack in one of the biggest courses at Rock the JVM: The Rock the JVM Companies Board, aka - "Trustpilot for Scala companies, with AI" Ain't that a billion $$ startup? Seriously, this

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Rock the JVM

@rockthejvm

2 years

New video! SBT tutorial, part 1 - essentials, adding libraries, running tests, all from scratch in the SBT console: cc @petr_zapletal @ScalaTimes

SBT in Scala (part 1) - Setting Up a Scala Project, Adding Libraries,...

Full SBT tutorial in Scala, written form:https://blog.rockthejvm.com/sbt-tutorial/Take the Scala Masterclass:https://rockthejvm.com/p/the-scala-bundleThis vi...

www.youtube.com

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@rockthejvm

10 months

MASSIVE article just landed on the blog: Practical type-level programming in #Scala - how to solve real-life problems with the most powerful features of the language: This article is the biggest yet on the blog... ...by 4x! 🤯 Enjoy!

Practical Type-Level Programming in Scala 3

Learn how to use type-level programming to solve practical problems.

blog.rockthejvm.com

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@rockthejvm

2 years

New (massive) video! #CQRS with #Scala , #Akka and #Cassandra in a realistic scenario: In partnership with @DataStaxDevs

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@rockthejvm

2 years

Learning #Scala gives you a different style of thinking and approaching code.

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@rockthejvm

4 years

This year: - published 4 courses - started a blog (twice) with now 53 articles - started a YouTube channel, now with ~60 videos, 3.7k subs and ~20h of content - held the first Black Friday sale on the site - went from 2 to 750 followers on Twitter Thank you all! Have a big 2021.

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@rockthejvm

2 years

Lesson #1 in functional programming: - instructions are executed - expressions are evaluated Think code as expressions, instead of instructions.

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@rockthejvm

4 years

Stop speculating bitcoins and start writing some #Scala . Has solid returns.

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Rock the JVM

@rockthejvm

2 years

In the final stretch recording the upcoming course. This thing is a beast, easily 2-3x bigger than the biggest course at Rock the JVM so far. The project feels less like a course and more like a rite of passage. Excited to show it to you soon!

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@rockthejvm

2 years

New video! Scala type-level programming - a hardcore Tic-Tac-Toe, which you can use to impress your next interviewer:

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@rockthejvm

2 years

What do you think of #Clojure ?

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@rockthejvm

3 years

Before writing fancy, write something that works first.

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@rockthejvm

10 months

I know next to nothing about marketing. My strategy is: If you like my work, tell your friends. If not, tell me.

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@rockthejvm

1 year

The people and teams improving and maintaining #Scala , libraries and tooling (e.g. @scala_sbt , @scalameta , @IntelliJScala ) are doing monumental and (mostly) thankless work. A little thanks and maybe a PR on GitHub would go a long way

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@rockthejvm

3 years

Be kind to folks maintaining OSS.

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4 years

2021 is going to be a big year for #Scala .

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2 years

#Scala has the potential to be be a full-stack powerhouse. What's missing?

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2 years

It's out, folks! Guess what's coming next... 😎

John A De Goes

@jdegoes

2 years

Ladies and gentlemen, I am pleased to give you... ...ZIO 2!!! 🎉🕺🎇 The future of functional programming has arrived. Read more now 👇

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@rockthejvm

2 years

Will be speaking at @scalarconf about end to end, full-stack apps in #Scala 3: - how Typelevel libs work together - how to design full-stack apps for no headaches - how to add features fast - how to keep the same mental model for both backend and frontend - building, deploying

Scalar Conference

@scalarconf

2 years

We’re excited to welcome @rockthejvm as the next #Scalarconf speaker! 😀 Daniel will be talking about a blueprint for building end-to-end, full-stack apps in Scala 3 using the Typelevel stack. Join us! 🎟️ #scala #functionalprogramming #conference2023

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4 years

New video! Structuring and organizing services with @zioscala and ZLayer, for modular, maintainable and composable code: cc @petr_zapletal @ScalaTimes @jdegoes

Structuring Services in Scala with ZIO and ZLayer

Written version: https://blog.rockthejvm.com/structuring-services-with-zio-zlayer/This is a video for comfortable Scala programmers. We learn to structure ou...

www.youtube.com

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@rockthejvm

1 year

Started recording the ZIO Rite of Passage. Probably going to be as big a course as the other one. #Scala

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2 years

Don't use #Java habits to write #Scala code, because you'll get the worst of both.

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@rockthejvm

1 year

Will speak at @scaladays in Madrid about effective learning and teaching!

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2 years

Advice for Java/Python folks touching a Scala code base "for 5 minutes to fix a bug": Those 5 minutes turn into 5 days searching for a hack. You need to think differently. Instead, spend 5 hours learning the basics.

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@rockthejvm

1 year

#Scala fans rejoice, Pekko 1.0 is out!

Apache Pekko

@ApachePekko

1 year

Apache Pekko 1.0.0 has been released, see and for more details. Its been a long road, many thanks to everyone who participated in this!

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3 years

Learning #Scala has a lasting positive impact on your thinking as an engineer, long after (if at all) you stop writing Scala.

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1 year

#Scala error: "Covariant type A occurs in contravariant position" #Kotlin error: "Type parameter A is declared as 'in' but occurs in 'out' position" @scala_lang , you can do this too! Make errors easy to understand and you'll attract people!

Rock the JVM

@rockthejvm

1 year

Make #Scala adoption irresistible by using Atomic Habits: 1. Make it obvious. Show people compelling results built with Scala, so much so that it's impossible not to get their attention. A few years ago, @Akka , @ApacheSpark , @PlayFramework and @Finagle built such powerful

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@rockthejvm

3 years

Monads have a hidden property: once somebody understands them, they have the impulse to write a tutorial about them.

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3 years

#Scala is worth learning not because it's hot, but because it's relevant.

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@rockthejvm

2 years

Too many programmers argue too much about syntax and too little about ideas.

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@rockthejvm

3 years

Refunded all purchases from Ukrainian 🇺🇦 students on the site over the last 30 days. You need that money more than anyone. Full access maintained, although it's quite clear that nobody in Ukraine is in the mood for Scala courses right now. 2/

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@rockthejvm

3 years

You don't need to be a mathematician to write good functional #Scala .

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9 months

It's hard to overstate how much mental burden the JVM has freed from the heads of developers.

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3 years

New video! A mini-bank app using #Scala , #Akka , Cats and #Cassandra - part 1 of a 2.5 hour mini-series on how to integrate Akka, Cats and Cassandra into a realistic project. Enjoy!

An Akka, Cats and Cassandra Project in Scala - Part 1

Written version:https://blog.rockthejvm.com/akka-cassandra-project/Full project: https://github.com/rockthejvm/akka-cassandra-demoThis video is part of a min...

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