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Free at launch · Open source · No signup

System design, zero to Staff.

The interactive platform that combines Educative structure, ByteByteGo diagrams, and Hello Interview coaching. See it. Scale it. Break it. Defend it.

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10K RPS · Single region, one Postgres
Correctness first. Adding Redis before you need it is over-engineering.
50+
System-design problems
40+
Interactive concepts
8
Company tracks
4
Scale tiers per problem
Five pillars

Built around how senior engineers actually think

Not a course, not a wiki. A system for turning curious engineers into confident architects.

Curriculum

Zero → Staff, taught visually. Every concept with diagrams, animations, and interactive simulations.

Framework

The Hello-Interview method as the platform's spine: Requirements → Core Entities → API → High-Level → Deep Dive → NFRs.

Practice

Playground, Failure Sim, Quiz, Cheat Sheets, Scale Slider — you don't just read, you build and break.

Coaching

AI Interviewer (bring your own key), delivery scoring, and speech-to-text mock — no $200/hr human coach required.

Growth

SEO landing pages, shareable OG diagrams, verifiable certificates, and a Learn-in-Public wall.

Company-specific coaching

Every company grades differently

What Meta rewards is not what Amazon rewards. We tell you what each company actually looks for.

Free at launch. Extensible forever.

Every concept, component, pattern, problem, and case study is authored in MDX + data. Adding a new system-design problem is a 15-minute contribution. The entire codebase is public and MIT-licensed.