Interview Experiences

Real candidates, real loops: every round, what was asked, and how it ended.

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14 stories

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OptiverSoftware EngineerIntern
Jul 2026

A 90-Minute OOD/State-Machine OA on CPU Core Cooling

I recently finished this company's Summer SDE Intern OA, so I'm writing this post to give back to the community. There were two parts in total. One part was a HackerRank OA (90 minutes), an OOD / state machine simulation problem — a puzzle game kind of like Tower of Hanoi. Problem overview Implement an OverheatPreventionController class to simulate and manage the temperature and cooling state of…

Online Assessment0
OptiverSoftware Engineer
Feb 2026

One OOD Problem and the Zap-N Reaction Games

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Online AssessmentPremium0
OptiverData Scientist
Feb 2026

A Three-Part OA With a Likelihood-Ranking Twist

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Online AssessmentXP0
OptiverSoftware Engineer
Jan 2026

Woken Up Mid-Sleep by HR's Call

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RejectedTechnical ScreenXP0
OptiverSoftware EngineerIntern
Dec 2025

Passed the Superday, Rejected in the Final Behavioral Round

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RejectedOnsiteXP0
OptiverSoftware EngineerIntern
Nov 2025

A Three-Part OA With System Design Coding and Zap-N Games

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Online AssessmentPremium0
OptiverData Scientist
Nov 2025

A Marathon of 17 Probability OA Questions

Pick a random integer from 1 to 10,000. What's the probability that every digit of that number is different? Roll a die until you roll something greater than 4. What's the expected value of the sum of all the rolls? Draw 3 cards from a standard 52-card deck. What's the expected value of the product of the three numbers (J = 11, Q = 12, K = 13)? Toss 100 coins. Pair up an H with a T and remove tha…

Online Assessment0
OptiverSoftware EngineerNew Grad
Nov 2025

Shipping-and-Plane-Capacity System Design Round

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RejectedTechnical ScreenPremium1
OptiverSoftware Engineer
Sep 2025

HackerRank OA: News Subscription System Design

✅ Interview experience summary: News Subscription System design (hands-on HackerRank question) 📌 Problem background (system design) You're a news aggregation service. The goal is to give users one unified system for subscribing to all news providers, so they only receive content they're interested in without being overloaded with volume. The system needs to manage large data streams efficiently a…

Online Assessment0
OptiverSoftware Engineer
Aug 2025

A Brutal Four-Section OA With Coding, Pattern-Finding, and Probability

I think their OA basically gets sent out to everyone — I got mine right after I applied. There are four sections and the intensity is pretty high. The email doesn't mention this, but you can actually do them separately, so I'd suggest doing one section per day. Coding The coding section lets you go back to earlier questions, so if you don't know how to solve one, I'd suggest skipping it first. 90…

Online Assessment0
OptiverSoftware Engineer
Aug 2025

Breaking Down the Four-Part OA

The Optiver OA is honestly pretty hard. This part is 2 medium-difficulty coding problems plus 1 approximate-solution problem, all in 90 minutes. The problem types lean toward DP (dynamic programming) and heap (priority queue) style problems — testing mathematical modeling, data structure simulation, strategy backtesting, and statistical analysis skills. Approach: before starting a problem, quickl…

Online Assessment0
OptiverQuantitative Researcher
Jul 2025

Six Rounds and a PhD-Shaming Final Call

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OnsitePremium0
OptiverQuant Trader
Jul 2025

A 30-Minute Coin, Dice, and Poker Betting Game

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RejectedTechnical ScreenPremium0
OptiverQuant Researcher
Jan 2025

Skipped the OA for a Trading Game, Still Rejected

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RejectedTechnical ScreenPremium0

What are interview experiences?

An interview experience is a candidate's own account of a hiring loop — not a question bank entry. It tells you the shape of the process: how many rounds there were, what each round actually tested, how long the gaps between them ran, and what the recruiter said at the end. That context is the part a question list cannot give you.

How to read them

Weight recent write-ups more heavily — interview loops change, often within a year. Read several for the same company and role rather than one: a single account tells you what one interviewer asked, while five tell you what the bar is. Note the outcome badge too, since a rejection write-up usually explains the gap far more precisely than an offer one.

Share your own

Every published experience earns 50 XP, and each of the first 3 likes it receives in a day earns you 10 XP more. Likes must come from established accounts; like-for-like swaps and likes from your own second account are not paid. Write it while the details are fresh — the round order, the exact prompts, and how much time you were given are what the next reader needs.

Share your experience to earn XP