Sharpen SQL.
Take the offer.
509 tasks — from the basics to real problems from Yandex, Tinkoff, Sber, Avito, Ozon screens. AI hammers your weak spots. Interview mode runs like a real tech screen.
From task to verdict in 3 minutes
No onboarding. Open it, write it, see where you blew it — back into the ring.
Pick a task
Topic, level, company — filters in one click.
Write SQL
PG or MySQL. EXPLAIN within arm's reach.
Get the verdict
Diff against canonical. AI puts a finger on the mistake.
Learn what they'll ask. Not what's in the textbook.
Analyst, backend, QA, data engineer — each role has its own set. Plus a dedicated interview-prep track.
Analyst
So your PM stops asking 'do you know SQL?'
- JOINs, aggregates, GROUP BY
- Window functions
- CTEs and nested subqueries
Backend
So your lead stops catching your N+1 in prod
- INSERT / UPDATE / DELETE and transactions
- Optimisation and EXPLAIN
- Complex subqueries and CTEs
QA / Testing
To test the data, not just UI clicks
- SELECT-based checks and filters
- Aggregates: counts, dups, anomalies
- DML for fixture setup
Data Engineering
To build data marts, not paste SELECT *
- DDL: schemas, tables, constraints
- Window functions and aggregates
- CTEs and complex transforms
AI builds the task on the exact thing you missed yesterday
Struggle with window functions? Five fresh cases land in your queue until they stick.
- Targets weak spotsLooks at your last 40 submissions and picks the topic you keep missing right now.
- Schema fits the caseAn AI task arrives with a schema and seed shaped for that exact scenario.
- Auto-gradedDiff against canonical on hidden seed. No reviewer queue.
- Tracks your levelOn a streak — difficulty climbs. Stalling — the next one drops a notch.
$ ai.generate(adaptive=true)
One slip and the screen is over.
Timer runs on the server, browser is locked, no hints.
Eight ranks, Junior to Titan.
Hit Senior and interviews stop scaring you.
Every solve earns power. Streaks, achievements, weekly leaderboard. Your closest rivals are visible.
- EASY · 10 power
- MEDIUM · 25 power
- HARD · 50 power
- EXPERT · 75 power
The axe is in your hand. Swing.
Two minutes to your first task. One month to the offer. Your move.
Claim your rank