A Coding Platform with Opinions
What CodeKairo is, the four rules the product follows, what has shipped, its honest limits, and who is building it: Ayaan Pathan, looking for a co-founder.
What is CodeKairo?
CodeKairo is a web-based coding practice and interview-preparation platform for college students and early-career software engineers. It provides more than 1,500 data-structures-and-algorithms problems judged by hidden tests in 13 programming languages, a 19-stage DSA roadmap, a daily coding contest, bug hunts on real broken code, language study plans for Java, JavaScript, C++, Python and SQL, AI-led mock interviews, an aptitude question bank, full-length placement mock tests modelled on company hiring patterns, a resume ATS analyzer, 1v1 and 2v2 coding duels, live pair-programming rooms, a community feed, coding tournaments hosted by colleges and clubs on CodeKairo Battles, and one rating, XP and streak system across all of it. A free account covers the core features; paid plans raise the mock-interview and bug-hunt limits.
Who is it for?
CodeKairo is built for students preparing for campus placements and coding rounds, and for working developers preparing for technical interviews. Prices are in Indian rupees and the product calendar — streaks, daily allowances, reminders — runs on Indian Standard Time; the daily contest changes at midnight UTC, 05:30 in India.
Principles
- Real tests or it didn't happen. Every verdict on the platform comes from running your code against hidden cases. There's no 'mark as solved' button and there never will be.
- Measure the work, not the tab. Timers pause when you leave. Streaks need an accepted solution. Numbers that can be gamed aren't worth having on a profile.
- Practice should look like the job. Bugs arrive as reports, not signatures. Interviews have a role and a round. Pairing happens in one editor, out loud.
- One place, one rating. Challenges, hunts, rooms and interviews all pay into the same profile. You shouldn't need four accounts to see how you're doing.
What has shipped
- Coding challenges — More than 1,500 DSA problems with hidden tests, hints and editorials, solvable in 13 languages in a workbench with custom test cases and a timer that pauses when you leave.
- DSA roadmap — A guided path of 19 stages in four tiers over about 150 curated problems, each stage with tutorials in four languages; a stage opens when the one before it is cleared, and every tier ends in a chest of XP and bonus mock interviews.
- Daily contest — One problem a day for everyone, ranked by time to Accepted plus penalties, with monthly and all-time standings and a contest streak.
- Study plans — A language taught in full — Java in 20 modules, JavaScript in 16, C++ in 20, Python in 20 and SQL in 16 — plus Low-Level Design in 7 and Competitive Programming in 12, with lessons, whole-program exercises judged on a real runtime, quizzes, checkpoints, a chosen pace and a certificate.
- Bug hunts — More than 300 debugging challenges on real JavaScript, Python and Java projects: a bug report, the code as shipped, and hidden tests that decide whether the fix is complete.
- Mock interviews — AI-led, timed interviews built from the role (39), round (16), depth (3), stack and focus areas you choose — written or spoken — with a report on what you were shaky on.
- Resume Deep Dive Interview — An AI mock interview on your own resume: it reads the CV and asks only about what is on it — each project, your part in it, the choices behind it and the numbers you claim — written or spoken, with every answer scored 0–10.
- System design practice — Nine system design interview questions — URL shortener, rate limiter, chat app, news feed and more — answered in sections and drawn as an architecture, then reviewed out of 100 on a fixed rubric, with the reference design in the notes.
- CS and system design notes — Interview notes on operating systems, computer networks, DBMS, OOP, system design and low-level design, taught through animated figures, with a direct answer, worked examples and interview questions on every page.
- Aptitude practice — More than 1,100 quantitative, logical, verbal, data-interpretation and programming questions with time targets, hints, worked solutions and per-topic progress.
- Placement mock tests — 29 full-length timed mocks — 26 modelled on company hiring patterns such as TCS NQT, Infosys, Wipro, Accenture and Amazon, and 3 CodeKairo practice papers — with sectional timing, negative marking where the real test has it and a fresh paper every sitting.
- Skill tests and certification — Timed certification tests in twelve skills — Java, Python, JavaScript, TypeScript, C++, C, Go, problem solving, SQL, OOP, operating systems and computer networks — at Basic and Intermediate level, with multiple-choice and output-prediction questions plus judged coding, that issue a verifiable credential, a certificate and a LinkedIn entry on a pass.
- Resume ATS analyzer — Scores a PDF or DOCX resume out of 100 against a job description with the reason behind every point, flags layout risks that break parsers and rewrites bullets without inventing facts; the score needs no account and the file is not kept.
- Coding duels — 1v1 and 2v2 duels on a problem or a bug hunt, matched by rating or played with friends in a private room; the first accepted submission wins, and matchmade wins pay XP and rating.
- Pair rooms — Live sessions of up to four people in one editor with shared runs and verdicts, chat and audio, and a room history with the final submission.
- Community — A feed of statuses, questions pinned to a problem or bug hunt, polls and achievement shares verified against the judge's records, with follows, saves, trending tags and a weekly bulletin; the public feed is readable without an account.
- Coding tournaments (CodeKairo Battles) — Colleges, clubs and companies host 1v1 knockouts seeded by rating and ICPC-style team contests on the same catalogue and judge, free; players enter with their CodeKairo account and every tournament solve counts on their profile.
- Rating, XP, streaks and leaderboards — One profile across everything: rating moves only on accepted submissions through five ranks, XP is additive, streaks need an accepted solution a day, and leaderboards rank by XP, problems solved and bugs fixed.
Who is building it
Ayaan Pathan, founder. LinkedIn
CodeKairo is built by Ayaan Pathan, its solo founder — the frontend, the backend, the judge integration, the timer that pauses when you tab away. It's early, it's live, and it's being built in the open.
I'm looking for a co-founder: someone who wants to own a real part of this — product, growth or engineering — rather than advise from the side. If you've read this far and something on these pages made you think "I'd have done that differently", that's the conversation I want to have.
Until then: the fastest way to help is to use it, break it, and tell me what's wrong.
Honest limits
- The problem set is growing. It's curated rather than enormous. Every problem has real tests and an editorial; there are fewer of them than on the big sites, on purpose.
- Interviews are practice, not verdicts. A mock session tells you where you were shaky. It doesn't predict an offer, and we won't pretend it does.
- It's one person's taste. The layout, the timer, the copy on this page. If you disagree with a choice, say so — a lot of the current design came from exactly that.