How to use this

This site has three kinds of material, and they are meant to be used in a loop, not read front to back.

Material	What it is	When to use it
🎤 Mock interviews	Full interviews by role and level, with graded answers	To find out where you stand today
🎓 Courses	10 courses, 44 modules with labs and self-checks	To close the gaps you found
📑 Question bank	389 questions with summary and detailed answers	To practise and to go deep on a topic

The loop

1. Diagnose (1 hour). Open the mock interview for your role and level. Read only the questions and answer out loud, on a timer. Then compare yourself against the three graded answers.
2. Study. Every question links to the course module that explains the mechanism. Do the module — including the lab, because nothing sticks without running something.
3. Practise. Go back to the bank and answer the related questions out loud in 30–60 seconds. If it takes longer, half of it is filler.
4. Simulate. Close with a timed mock and score yourself with the rubric at the end of each interview.

Three rules that make the difference

Answer out loud, on a timer. A correct four-minute answer is a failed answer. The bank’s format — summary plus detail — exists for that: the summary is what you say, the detail is what supports the follow-ups.

Do the labs. You cannot sound credible about a GC pause, a pprof profile or a Kafka rebalance if you have never seen the real output. Ten minutes in a terminal beat an hour of reading.

Study the mistakes, not just the right answers. Every module has a “common mistakes” section and every mock interview has a ❌ answer. Those are the exact phrases that make an interviewer downgrade you — and most of them sound perfectly reasonable.

The three-level rule: for any topic you should be able to answer in 30 seconds (what it is), in 3 minutes (how it works internally and its trade-offs), and with a story of your own (when you used it or broke it). If the third level is missing, build the lab that gives it to you.

Where to start depending on your time

• You have an interview next week: the 10-day sprint — and if you only have three days, distributed-systems fundamentals plus your STAR stories.
• You want to change league, not pass an exam: the 8-week track in the same study plan.
• You just want to check where you stand: one mock interview for your role, timed, recorded.

A note on language

The mock interviews, this guide and the study plan are fully available in English. The question bank and the courses are still in Spanish: you will see them here with a notice at the top of the page. Translations are welcome — the content lives as plain Markdown in the repository.