Rozoomio — Serious topics. Playful learning.
Elixir
Become the developer AI can't replace.
The most valuable skill in the AI era: reviewing code with confidence.
AI can generate the code. You still need to know whether it is correct, efficient and safe to ship.
Train the engineering judgement that helps you review AI-generated Elixir with confidence.
AI can generate code easily.
Anyone can ask AI for a solution.
Experienced engineers know when there's a better one.
Can you spot when:
- → Stream should replace Enum?
- → reduce/3 hides an accidental O(n²) operation?
- → flat_map/2 removes an unnecessary pass?
- → Enum.into/2 expresses the intent more clearly?
Knowing the API isn't about remembering functions. It's about making better engineering decisions.
That's the difference between code that works…
…and code you'd merge.
Learn less. Retain more.
Through adaptive retrieval practice, you:
- ✓ keep the APIs ready when you need them
- ✓ retain them for longer
- ✓ remember more with less repetition
- ✓ build lasting API knowledge
- ✓ turn short-term familiarity into long-term recall
This is for you if:
- ✓ You're learning Elixir and want to master Enum & Stream through real code examples.
- ✓ You use AI to write Elixir and want to spot edge cases, inefficiencies and better alternatives.
- ✓ You've been writing Elixir for years but still discover Enum functions you didn't know existed.
- ✓ You want a quick, practical way to validate what you know and uncover what you don't.
- ✓ You prefer learning through short code examples instead of long courses or tutorials.
- ✓ You want to fit learning naturally into your workday.
The creator
Created by a developer, for developers.
🧑💻
Tetiana Dushenkivska, founder of Rozoomio.
I've spent over 10 years building production systems with Elixir and helped hundreds of developers learn through evidence-based practice.
When I first started learning Elixir, I understood the concepts after reading books and taking courses—but I couldn't remember the APIs when I needed them. So I created a set of physical flashcards for myself to move the standard library into long-term memory.
What started as a personal learning tool became a product, with more than 5,000 physical Elixir flashcard decks sold to developers around the world.
Today, AI can generate almost any API call in seconds. You're still responsible for what reaches production. The real skill is spotting AI mistakes, recognising edge cases, and signing off with confidence.
That's why I built Rozoomio. It takes everything I learned from creating the original flashcards and combines it with active recall, distributed learning and microlearning to help developers strengthen the skill that matters most in the AI era: engineering judgement.
I'm building the product I want to use myself—one that helps me stay sharp, review AI-generated code with confidence, and keep learning without spending hours on courses.
The package
What's included
- ✓ Lifetime access to the Enum & Stream collection.
- ✓ Comprehensive coverage of the Enum & Stream APIs through hundreds of carefully designed code examples, including common patterns and edge cases.
- ✓ Adaptive retrieval practice that automatically focuses on the APIs and examples you haven't mastered yet.
- ✓ Detailed explanations for every question, so you understand not only the correct answer but why it's the better choice.
- ✓ Knowledge gap tracking to help you measure your understanding and see what to practise next.
- ✓ Future updates to the Enum & Stream collection at no additional cost.
- ✓ Desktop and mobile access, so you can learn wherever you are.
I built this because I wanted it myself.
If, after trying Rozoomio, you don't think it helps you become a more confident Elixir developer, email us within 3 days of your purchase and we'll issue a full refund.
- ✓ Full access from day one.
- ✓ No subscription.
- ✓ No hidden fees.
Good to know
Frequently asked questions
Is this for beginners?
Yes. If you're learning Elixir, the questions help you build confidence with the Enum & Stream APIs through practical code examples. Every question includes an explanation, so you learn as you go.
Rozoomio is designed to help you master the standard library through practice, not teach Elixir concepts from scratch. If you're looking to learn the language itself, start with a book or course and use Rozoomio to reinforce and retain what you've learned.
I've been using Elixir for years. Will I still learn something?
I built Rozoomio after years of writing Elixir because I didn't have time to keep revisiting the documentation looking up functions I'd forgotten. I wanted a way to stay sharp without interrupting my day.
If AI can write the code, why should I learn this?
If you're happy to treat AI as a black box, Rozoomio probably isn't for you.
If you want to understand Elixir deeply and build confidence in your own knowledge—Rozoomio will do just that.
How long does a learning session take?
As long as you want.
Most questions take about 30 seconds to answer, and you can stop and continue whenever it suits you.
To get the most from the adaptive retrieval practice, you'll typically spend 5–15 minutes completing the cards scheduled for that day.
Is this a subscription?
No. It's a one-time purchase with lifetime access to the Enum & Stream collection, including all future updates.
Can I use it on my phone?
Yes.
Rozoomio works on both desktop and mobile.
On desktop, you'll type your answers for a stronger active recall experience. On mobile, you can answer using multiple choice, making it easy to practise wherever you are.
What if it's not for me?
If, after trying Rozoomio, you don't think it helps you become a more confident Elixir developer, email us within 3 days of your purchase and we'll issue a full refund.
Are the questions AI-generated?
The questions are AI-assisted and reviewed by an experienced Elixir developer before being published.
If you ever spot something that could be improved, you can report it directly from within the platform.