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Become a senior engineer

We teach powerful, niche technologies used at scale, and solid mental models on type safety, concurrency and system design — the kind of judgment that separates senior engineers from everyone else.

Skip AI chats and shallow answers, and follow a smooth learning curve where code is king.

30+ courses 250+ hours of content Since 2017

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Why Rock the JVM?

100% Hands-on

Every course is built around writing code, solving real problems, and discussing engineering decisions you'll likely face as you grow in your career.

Niche Technologies

We teach non-mainstream topics, languages and mental models. They're usually hard, and finding good resources is even harder. We've done all the work so your learning curve is smooth. Just take the course, and you'll have the skills without needing to go anywhere else.

Breadth or Depth? Yes

You can go deep on one topic or branch out as you like. Courses are built to stand alone, but they all connect. Senior engineers have both broad foundations and deep knowledge spikes, and here you can build your own.

What You'll Master

Deep dives into powerful technologies — from language fundamentals to production-grade distributed systems.

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One membership. The whole library.

Your path to senior engineer

All of Rock the JVM, at your fingertips.

Get full access to 250+ hours of premium content across Scala, Kotlin, functional programming, distributed systems, and big data.

Full access to the premium Rock the JVM catalog
New courses included automatically as the library grows
Private community access — kept even if you cancel
Cancel any time

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For companies and teams

Upskill your engineering team

Companies like Google, Apple and Adobe have used Rock the JVM to train their engineering teams. Give your engineers structured, deep learning on the technologies they ship with.

Full library access for every seat
Individual accounts with personal progress tracking
Flexible pricing based on team size
Tax-compliant invoicing for easy expensing
Direct support from the founder

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100,000+

engineers trained worldwide

250+

hours of hands-on content

Since 2017

trusted by teams at Google, Apple, Adobe and more

What Our Students Say

Trusted by 100,000+ students worldwide

My team is expanding the use of Akka in our products so I needed a quick introduction on this topic. I have tried a couple of courses but the introduction to Akka was always too abrupt, too hard to comprehend. I blamed Akka for this as being too hard to explain. This was until I was exposed to the Rock The JVM courses which were an absolute delight when it comes to presenting such complex topics in such an easy to understand way. And Daniel has not stopped at Akka but has added to his portfolio amazing courses on Scala and Spark too. It seems like he is quite enjoying taking such challenges like complex technologies and making them so simple for everyone. I have instantly recommended Daniel’s work to my team, which helped them immensely with taking their skills to a new level, and I do recommend these courses to anyone who wants to have the fastest ramp-up in these tough but popular technologies.

Mihai Fecioru
Adobe · California
From Scala, to Akka, to Spark, Daniel delivers exceptional material in each and every one of these technologies. I’ve been using them for a long time and there is always something new I will discover from him. The level of detail he gets into as well as the way he delivers material is mindblowing. I personally find his latest course Spark Optimization pure gold and one of a kind. I’ve been using Spark for a year now and I haven’t even thought how much you can leverage query plans to make such optimizations. I can’t stop thinking every time, how he manages to go so deep - because using a technology is one thing, but knowing its internals so well and how everything works behind the scenes is another story when it comes to distributed systems. Long story short Daniel is definitely the best instructor I’ve come across and each one of his courses is the best resource you can find online. Kudos for all your work and knowledge sharing.

Giannis Polyzos
Ververica · Greece
Daniel’s courses on Scala and Big Data are the best in class. I’ve been in touch with Daniel’s teaching and courses since early 2018. The first course that I took from him was Scala & Functional Programming; I was skeptical about it because over the internet there are many courses you can find, but few really worthy. I remember the very first day when Daniel started to speak and shared his examples - I started to love Scala, and then more as we went on. I am with Scala for the last 5 years now, but never ever has anyone explained to me or gave me comparable resources to Rock the JVM. Daniel gave me a shift in life and helped me crack top tech company interviews. His courses on big data are a must for any aspiring big data developer or data enthusiast. I highly recommend Daniel as an educator both online and on campus.

Anirban Goswami
Apple · California

Before you join

Is Rock the JVM for you?

We're not for everyone. Rock the JVM is built for a specific kind of engineer who wants to go deep.

This is for you if…

You're a working software engineer with at least a year of experience
You learn best by writing code
You want structured, deep learning instead of quick answers (e.g. from AI)
You need to understand non-mainstream languages, tools and ecosystems
You value robust code and good architecture
You don't want to spend $5000+ for training from $FAMOUS_COMPANY with slides

This is NOT for you if…

You're just starting to learn to code
You believe coding is dead
You are already comfortable with your preferred language or stack
You need answers and results quickly
You prefer passive watching (we write lots of code)
You take courses for certificates only

How we stack up

Rock the JVM vs. the alternatives

There are a lot of places to learn online. Here's how Rock the JVM compares for the engineer who wants to level up seriously.

Feature	Udemy	Coursera	O'Reilly
Deep content on niche tech (e.g. Scala, effect systems)		limited	limited
Code-first teaching	some	some
Non-trivial projects	rarely	some (capstones)
Senior-level content	rarely	some
All-access membership	limited
Private community		limited (forum)

Free Resources

Latest Articles

Latest Videos

13 - Simon Peyton Jones on Haskell, Verse, Strong Type Systems and Tasteful Abstractions

Apr 16, 2026 • 1h 24m

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Daniel Ciocîrlan

Bio and courses

👋 from the founder

I'm Daniel Ciocîrlan, and I'm a software engineer like you. Over 15+ years, I've read books and blogs, taken online courses, watched a zillion tutorials, and maxxed out my AI tokens as I've learned the (hard!) things I needed for my projects.

I found two underrated questions to ask if you want to learn hard technical topics:

What to search for (or what questions to ask, in case of AI)
In what order to study them

If only someone could give you those answers. Without them, I've tried and failed many times, as I spent literally thousands of hours studying and practicing.

I made Rock the JVM because there's a smarter path to the same skills. We've deconstructed and sequenced the major ideas, tools, and mental models, so that you can get the same lessons 10x faster than I did.

There's no instant shortcut and we write a LOT of code, but this is the learning path I wish I had.

Since 2017, over 100,000 students around the world have taken our courses, and major companies like Google, Apple and Adobe have reached out to me to run private training sessions for their teams.

Join Rock the JVM and put in the work with us, and you'll build the senior engineer profile you want.

See you inside,
Daniel

Frequently Asked Questions

Need a course or training session?

Send me a message and let's talk about your needs.