System Design
Architect scalable systems, discuss trade-offs, and navigate complex design constraints.
Interview modes
Choose the interview format you are preparing for
Practice system design, coding, behavioral, or a custom problem from a real interview.
Coding Round
Code in JavaScript or Python while Ada checks your reasoning, tests, trade-offs, and edge cases.
Behavioral Round
Turn loose stories into crisp STAR answers against company-style competencies and follow-ups.
Custom Problem
Paste a problem or job description and generate a verified interview setup with examples and tests.
Why it works
Everything a real interview throws at you
Not flashcards. Not solutions to memorize. A live interviewer that pushes back the way humans do.
Voice-first interviewer
Speak your thinking out loud — Ada listens continuously, responds with natural voice, and your words become an editable draft before you commit.
Reads your code live
Ada sees your editor and your test results in real time. If your explanation and your code diverge, expect to get called on it.
Hidden edge-case tests
Visible tests while you work, hidden edge cases at report time — exactly like the cases a real interviewer keeps in their back pocket.
Hints without spoilers
Stuck? A graded hint ladder nudges you toward the insight without ever handing you the algorithm name or the answer.
Bring your own question
Half-remember a problem from a real interview? Describe it and the AI builds a complete, verified mock interview around it — examples, tests, hints and all.
A hiring-style report
Finish and get graded on correctness, complexity, and communication — with specific moments from your interview cited as evidence.
How it works
From nervous to prepared in three steps
Pick your problem
Choose from 30+ curated questions across Easy, Medium, and Hard — or paste one you saw in a real interview and let the AI build it out.
Interview out loud
Clarify, state your approach, code in JavaScript or Python, run the tests. Ada probes your edge cases and invariants along the way.
Get your report
Hidden edge cases run against your final solution, and you get a hiring-style assessment of what you nailed and what to drill next.
The question bank
Patterns that actually come up
Curated like a hiring loop, not a textbook
Every question ships with clarifying answers, a hint ladder, common-mistake probes, hidden tests, and reference solutions verified in both languages.
- Classic screens: Two Sum, Valid Parentheses, Binary Search
- Core patterns: sliding window, BFS/DFS, dynamic programming, heaps
- Hard rounds: Trapping Rain Water, Median of Two Sorted Arrays, Word Ladder
- Company-style scenarios like fraud-rule parsing asked at fintech screens
Easy × 8
Medium × 14
Hard × 4
Arrays & hashing
Sliding window
Two pointers
Binary search
Graphs · BFS/DFS
Dynamic programming
Stacks & monotonic
Heaps · Top-K
Intervals
Strings
Sample report
Leave with a clear next practice plan
Every session ends with a hiring-style readout: what worked, what missed, and exactly what to drill next.
8.4
Overall interview readiness
Hidden tests passed 5/5. Communication was strong, with one complexity explanation gap.
Strong
You clarified inputs early, narrated the hash-map invariant, and recovered quickly after a failing edge case.
Improve
Your first complexity answer was correct but rushed. State time and space before the interviewer asks.
Evidence
Ada cites moments from your transcript, code runs, hint usage, and hidden-test outcome.
Next drill
Do two medium hash-map questions while speaking edge cases out loud before running tests.
FAQ
Questions, answered
Do I need an account or a credit card?
A free account, yes — you'll be asked to sign in when you start your first mock interview, so your sessions and reports stay with you. Two interviews are on us; after that, a card is needed for locked interviews, extra tokens, or a subscription.
How is this different from grinding LeetCode?
Solving problems silently is half the skill. Interviews test whether you can clarify, narrate trade-offs, defend invariants, and recover from probing — that's exactly what Ada drills.
Does it really run my code?
Yes. JavaScript runs in a sandboxed browser worker and Python runs server-side, against real visible tests while you work and hidden edge cases at report time.
Will the interviewer just give me the answer?
No — Ada is explicitly forbidden from naming the algorithm or revealing the approach early. Hints arrive as graded nudges, the way a good interviewer keeps an interview alive.
Can I practice a question from a real interview I had?
Yes. Describe it — even half-remembered — and the AI authors a complete question with examples, tests, and hints, then verifies its own reference solutions before adding it to your bank.