The platform built for
Data Engineers
The only place you can practise PySpark, Python & SQL by actually running the code — plus System Design interviews graded by AI like a real senior interviewer.No cluster. No Docker. No 45-minute setup that breaks on your Java version.
Trusted by 500+ data engineers at Amazon, Meta, Google & more
Trusted by engineers at
Four tracks.
One platform.
Master the exact technologies and interview rounds tested at top companies — coding and system design.
Interview-ready in 4 steps
Our workflow mirrors exactly how real technical interviews are structured.
Filter by PySpark, Python, SQL, or System Design. Choose your difficulty — Easy, Medium, or Hard.
Clear description, real dataset, expected output, and a starter code template.
Code directly in our Monaco editor (VS Code in your browser). No installs needed.
Instant pass ✅ or fail ❌. See exactly where your output differs from expected.
Watch it in action
See how to select a question, write real code in the browser, run it and instantly see if you pass or fail.
Built specifically
for data engineers
Your PySpark, Python and SQL runs on actual engines — PySpark 3.5, real Python, SQLite. Not mocked, not simulated.
Every question has expected output. No ambiguity — you either pass or fail, immediately.
See the optimal solution after attempting. Learn the best patterns and improve fast.
The same editor as VS Code. Syntax highlighting, autocomplete, shortcuts you already know.
Know exactly which questions you've solved. Focus your prep where it matters most.
Coding gets you the interview.
System design gets you the offer.
Every senior and staff data engineering loop has a round that LeetCode-style prep can't touch — and most candidates walk in having never practiced it once. We fixed that.
- 48 real scenarios, 4 seniority tiers — from your first system design round to Staff/Architect platform questions, across CDC, streaming, lakehouse, and orchestration.
- Graded like a real interviewer, not a quiz — scored across Requirements, Architecture, Data Modeling, Scalability, Trade-offs and Communication. No binary pass/fail.
- See what a strong answer actually looks like — every question ships with a model answer, so you know the bar before you walk into the real thing.
Trusted by engineers
worldwide
Real feedback from engineers who landed their dream roles.
"The only platform with real PySpark execution. The questions are spot-on for what top companies actually test in data engineering rounds."
"Instant feedback after every run changed how I learn. I could iterate fast and really understand where my code was going wrong."
"Finally a platform that understands what data engineers actually do. No more irrelevant LeetCode grinds. Highly recommend."
"DataCodingHub is the most targeted prep I have found for data engineering roles. The SQL and PySpark questions are exactly what gets asked in real interviews."
"Loved the real code execution — no more guessing if my solution is right. The instant pass/fail made my preparation so much more focused and efficient."
Ready to get hired as a
Data Engineer?
Join 500+ engineers already practising on DataCodingHub. Start free — no credit card needed.