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SystemCraft

Newv1.0 is now livearrow_forward

Master System Design
Like a Real Interview.

The first simulator that grades your architecture in real-time. Build systems, face chaos events, and get AI feedback — all before the actual interview.

Trusted by 2,400+ engineers

See it in action

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Design canvas with nodes
Feature

Canvas

Canvas
AI interviewer chat
Feature

AI Interviewer

AI Interviewer
Evaluation results dashboard
Feature

Evaluation

Evaluation
Chaos mode node failure
Feature

Chaos Mode

Chaos Mode
Analytics and progress tracking
Feature

Analytics

Analytics

Everything you need

Core Features

A complete system design interview simulator — from canvas to chaos to evaluation.

draw

Interactive Design Canvas

Drag-and-drop Load Balancers, App Servers, SQL Databases, Redis Caches, Message Queues, and CDNs. Wire them together and build real architectures — not just diagrams.

balance
LB
dns
Server
storage
SQL
memory
Cache
queue
Queue
cloud
CDN
robot_2

AI Interviewer

Gemini-powered interviewer checks in every 5 minutes with probing questions and nudges.

warning

Chaos Mode

Mid-interview node failures and traffic spikes. Fix it in 5 minutes or lose marks.

rule

Structural Linter

Real-time detection of disconnected nodes, missing caches, and single points of failure.

workspace_premium

Deep Evaluation

Score 0–100 with AI-generated strengths, weaknesses, and suggestions. Structural rules + Gemini reasoning combined into one final grade.

84/100
speed

Load Simulation

Run traffic simulations to see which nodes bottleneck under 100k RPS.

monitoring

Progress Analytics

Score trends, structural rule heatmaps, and weakness frequency across all sessions.