Learn · interview prep · free, no sign-up

Interview prep.

The course teaches it; this gets you hired. See what each company asks, work the classic problems, sit a timed mock (alone or with a real person), and revise the night before.

lessons revised: –/66
labs cleared: –/8
mocks done: –/4
study plan: …

how each tool works →

who's hiringPrep for a company

What candidates reported, with sources, and the lessons that teach it.

showing 12 of 45 · search above or see them all

All 45 companies Question bank · 353 questions · 292 reported

Company names and logos are trademarks of their owners, shown only to identify each company. This course isn't affiliated with or endorsed by any of them.

classic problemsThe questions everyone asks

Short walkthroughs that link into the full lessons.

Low-level design

Machine coding: classes, interfaces, patterns

interview nightRevise fast

For the evening before, or the train to the office.

revision decks

Five minutes a lesson

Swipeable cards: key ideas, numbers to remember, the trade-off table, classic mistakes and what to say when asked.

revise a world

604 cards · 66 lessons

cheat sheets11 worlds

A whole world on one page

Prints on a single A4 or Letter sheet. Download it as a PDF or share the link.

open a sheet

print · PDF · share

design sheets21 side quests

A whole design in ten minutes

Each side quest on a few pages: the numbers, the architecture with real tech icons, sequence, class and state diagrams, the decisions and what breaks.

open a sheet

141 diagrams · PDF · share

the real loopDo it for real

Timed rounds, a real person, working code.

code labs

Implement it in Python

A rate limiter, an LRU cache, a hash ring, an outbox relay: write it in the browser and run it against hidden tests.

runs on your device

mock interviews

The real loop, timed

An unseen problem from a fictional company, a named interviewer, curveballs, then a levelled rubric and a verdict.

4 loops between worlds

peer mockswith a real person

Practise with another learner

Post a time and a mock, someone pairs up, you both get a free video room. One interviews, then you swap.

needs an account

toolsNumbers and a plan

Estimate out loud; plan to your interview date.

numbers playgroundworks offline

50k QPS × 2 KB × 30 days = ?

Type an estimate the way you'd say it and get the worked answer, next to the latency and size numbers the course teaches.

calculator · reference numbers

study planner

Plan to your interview date

A day-by-day plan from your real progress, with revision days at the end. Fall behind and it adjusts.

calendar file · Google Calendar