RADIO practice · AI coach · mock interviews

Become the engineer who directs AI
in system design interviews

Practice scope, architecture, and tradeoffs with RADIO — then review your work like a staff engineer. AI coaches and probes; you own the design.

Built for interviews at product-led companies and high-growth startups — from FAANG-scale loops to lean frontend teams.

20 system design practice questions · AI coach · calibrated review · mock interviews on Premium.

Product-led techHigh-growth startupsFAANG-scale loops
27 free challenges
50+ questions
12+ case studies

Experience the Platform

Try solving a real problem with our interactive code editor. See how it feels to learn with CrackIt Dev.

Judgment training, not answer keys

Content library plus AI practice that makes you specify, trade off, and review — the work AI cannot do for you.

System Design

Real-world frontend system design case studies with architectural diagrams and step-by-step solutions.

12+ case studies

RADIO practice + AI coach

Work through requirements, architecture, data, interface, and tradeoffs. The coach asks; you design.

20 questions

Mock interviews

45-minute timed text sessions with a senior FE interviewer persona and a performance report.

Reports + history

JavaScript Problems

Master advanced JavaScript with problems on closures, promises, async/await, and more.

25+ problems

UI Component Coding

Build reusable UI components from scratch without libraries. Master machine coding rounds.

11+ components

Concept Questions

Master interview concepts with detailed explanations across React, JavaScript, TypeScript, and more. Start free and unlock the full 50+ question bank with Premium.

50+ questions

DSA Problems

Data structures and algorithms problems curated specifically for frontend interviews, with increasing difficulty from Free to Premium.

35+ problems

AI Code Reviewer

Get instant AI-powered feedback on your code. Improve code quality, best practices, and catch bugs before interviews.

Unlimited reviews
Coming Soon

Quiz Challenges

Test your knowledge with multiple choice questions across all frontend topics.

Why we built this

Built by an engineer who failed the rounds that mattered

I failed a frontend system design interview because I could solve LeetCode but had never practiced designing real products out loud with feedback. CrackIt Dev is the tool I wished existed — structured practice, honest scoring, and a path from “I think I know this” to “I can defend this in a room.”

Loved by Developers

Feedback from developers using the platform

The system design section is really well structured. I cracked multiple frontend interviews after going through the case studies and UI component challenges.

H

Harshit C

Frontend Developer

@ Swiggy

Good collection of DSA problems and JavaScript challenges. The difficulty progression makes sense and helped me move from failing JS rounds to consistently reaching final interviews.

A

Akshat

Full Stack Developer, SDE 2

@ CodeAcademy

Great platform for frontend interview prep. The UI components section aligns well with what companies actually ask, and the structure made it easy to fit prep into my week.

M

Meghana

UI/UX Engineer

@ Class Plus

Finally a prep platform built for frontend roles. Machine coding and JS rounds felt much less intimidating after working through the challenges here.

R

Rahul K

Senior Frontend Engineer

@ Razorpay

Simple, Transparent Pricing

Start free. Upgrade when you're ready.

YOUR PLAN

Free

$0

Perfect for getting started

  • 27 frontend coding challenges
  • 1 free AI mock interview + report (after RADIO + review)
  • 2 scored RADIO submissions
  • System design previews
  • Basic code playground
  • AI code review (3/day)
Start Free
MOST POPULAR

Premium

$19/month

Full library + AI system design practice (mock, RADIO coach, scores).

  • All free features
  • Full content library (DSA, UI, JS, system design)
  • Unlimited AI code review
  • All 20 system design practice questions
  • RADIO practice + AI coach (you lead; AI nudges)
  • Calibrated review scores + session history
  • 8 AI mock interviews per month + reports*
Get Premium

Premium Yearly

$228$149/year

Same as Premium — save vs paying monthly at list price.

  • All free features
  • Full content library (DSA, UI, JS, system design)
  • Unlimited AI code review
  • All 20 system design practice questions
  • RADIO practice + AI coach (you lead; AI nudges)
  • Calibrated review scores + session history
  • 8 AI mock interviews per month + reports*
Get Yearly

Lifetime

$349$249
one-time

Best value if you want ongoing prep, all future updates, and never want to worry about subscription renewals again.

  • Everything in Premium
  • Lifetime access
  • All future updates
Get Lifetime

Frequently Asked Questions

We focus on frontend system design judgment: RADIO practice with an AI coach that does not give away answers, calibrated review on 20 questions, and mock interviews — plus DSA, JavaScript, and UI challenges. You learn to direct AI and defend tradeoffs, not copy generated architectures.
  • The practice coach asks questions — it will not spoil requirements, diagrams, or tradeoffs.
  • Every submit is scored against the same calibrated rubric for that question.
  • RADIO steps, canvas, notes, and session history in one workspace — not scattered chat threads.

ChatGPT is great for brainstorming; CrackIt Dev is for interview-shaped practice.

No. The coach nudges with questions; the mock interviewer probes your thinking; the reviewer scores your submitted work. You own the whiteboard and the tradeoffs — the same expectation as a real loop.
Your notes, diagrams, and chat transcripts are sent to our AI provider (Anthropic) only to run the feature you requested. We do not use your content to train our models. See our Privacy Policy for details and retention.
Yes! 27 free coding challenges, system design previews, and limited RADIO practice. Premium unlocks all 20 practice questions, review, and mock quota.
Yes, you can cancel your subscription anytime through your account settings. Your Premium access will continue until the end of your billing period. After that, you'll revert to the Free tier but keep access to your progress history.
We add new challenges, problems, and case studies regularly. Premium and Lifetime members get access to new content as it ships.
Not yet, but our website is fully responsive and works great on mobile browsers. We're planning a mobile app in the future.

Practice like the architect in the room

Free: 2 scored RADIO designs on select questions. Premium: all 20 + unlimited + mocks.

Start Learning Free