System design is the ceiling for most engineers. We make it the floor.
150+ structured problems, an in-browser diagram canvas, and guided case studies — built for engineers who already know how to code.
Trusted by 12,000+ engineers · Stripe · Cloudflare · Meta · Shopify · Coinbase
Leetcode taught you to code. Nobody taught you to think at scale.
System design interviews separate senior engineers from staff — and most preparation resources are shallow, disconnected, or purely theoretical. You don't need another blog post about Twitter's architecture. You need a place to actually practice building systems, breaking them under load, and articulating tradeoffs out loud.
Four tools. One coherent system for getting interview-ready.
Build real architectures in the browser. No whiteboard required.
Drag, connect, and annotate system components on a fully interactive canvas. Design a CDN, a message queue, or an entire microservices topology — then get structural feedback before you step into the room.
Walk through real architectures, decision by decision.
Guided, step-by-step breakdowns of Twitter's timeline feed, Uber's dispatch system, Discord's message fanout, and more. Not summaries — structured deep dives with embedded questions at every tradeoff point.
150+ problems organised by domain, difficulty, and company.
Consistent Hashing to CRDT, Rate Limiters to Service Mesh. Every problem includes back-of-envelope estimations, architectural constraints, and a structured solution rubric used by actual staff-level interviewers.
Timed mock sessions with AI-powered structural feedback.
Simulate a real staff-level system design interview: 45-minute timer, intentionally ambiguous requirements, and an AI evaluator that scores your solution on scalability, consistency, and availability tradeoffs.
“Design a real-time collaborative editing system. Assume 10M DAU with up to 500 simultaneous editors on a single document.”
See what you're actually solving.
Every problem includes back-of-envelope estimations, structured tradeoff rubrics, and reference solutions reviewed by engineers who've cleared staff-level loops at top companies.
Showing 24 of 150+ problems
View all →Design systems visually. In the browser. Right now.
No Lucidchart. No Miro. No setup. A purpose-built canvas that understands the difference between a cache and a message queue — and helps you reason about it.
No whiteboard needed
Everything runs in the browser. Open a problem and start drawing within seconds.
Typed components
Every node knows its role. Caches, queues, databases, and gateways each have distinct validation rules.
Structural feedback
The canvas checks your design for common architectural anti-patterns as you build.
Real engineers. Real momentum. Real pressure.
A global leaderboard, daily streaks, and domain mastery badges — built to keep senior engineers accountable without feeling like a language-learning app.
I spent three months on Leetcode and thought I was interview-ready. Sysiq showed me how shallow my system design knowledge actually was. Three weeks in, I was walking through Kafka partitioning strategies without notes.
The diagram canvas changes everything. I used to freeze up when asked to whiteboard a design. Now I have a mental model I can actually articulate under pressure. The typed nodes alone — knowing the difference between a queue and a cache at the schema level — fixed gaps I didn't know I had.
The problem depth is real. This isn't surface-level 'here's how to design Twitter' content. They go into the tradeoffs, the failure modes, the back-of-envelope math. That's what interviewers at staff level actually care about.
Everything that matters. Nothing that doesn't.
The full breadth of what a staff-level engineer is expected to know. Organised by domain so you can identify and close specific gaps rather than re-covering ground you already own.
Distributed Systems
Caching
Storage
Messaging
Networking & APIs
Real-time Systems
Security & Auth
Infrastructure
Can't find a topic? We add 4–6 new problems and deep dives every month — community-voted, reviewer-approved, and shipped with full solution rubrics.
One decision. No traps.
Start free and begin solving immediately. Paid plans will return once checkout is fully integrated.
Enough to know if this is worth your time.
No credit card required. Billing options will appear after payments launch.
The engineers who get staff offers didn't get lucky.
They just prepared differently.
Stop reading architecture summaries. Start building systems, breaking them under load, and articulating tradeoffs with precision. That's what the interview tests — and that's exactly what Sysiq trains.
No credit card. No setup. First problem in under 60 seconds.