System Design Interview Questions [2026-2027]

In our company, developers don’t have access to the staging Kubernetes cluster at all. Only infra/ops does. The problem is that when something breaks on stage, infra often asks devs to debug applicati

I find this part of the interview often the most unrealistic because often times the answer should be - use the DB that the company has software infrastructure for. In practice, I'd probably start wit

Whenever I've been on a project that had to solve a scaling challenge the solution was something we discussed as a team. Yet these questions come up and it feels like my answers for them are insuffici

Telephonic. 1.) Do basic string match. Assume only one in the pattern. Follow up: Assume any number of s Onsite 1.) Windowed Average. Your are given a...

Design a WhatsApp Chat messaging system design. Functional Requirements: 1:1 chat messages Read Receipts Last Seen Starred Messages Messages may contain media Non Functional Requirements: Scalabale Fault Tolerant Resilient - in the...

My experience regarding recent SSE interview rounds with Confluent - I took a referral. After 20 days, recruiter called me and asked to schedule a Qualifer round. Qualifier Round: I was asked a DSA+LLD...

**Company:** Tekion **Round:** Technical (DSA) **Date:** 4th April 2026 **Type:** Hiring Drive **Difficulty:** Medium-Hard # Context Attended a Tekion hiring drive on **4th April 2026**. This was the

Recently gave wayfair onsite loop. Following were the rounds System design round \t Tiny URL \t\t With focus on scaling, key generation, partitioning etc. \t\t Want you to explain your choices. Application design \t...

Phone Screen: Implement a data structure to store key-value entries within a time-based interval. Slight variation to LRU Cache. Round 1: Implement a Word Search Engine, given a list of documents with text,...

Hi everyone Here\'s a compilation of recent questions for Wayfair\'s LLD round. 1. Parking Lot - https://leetcode.com/discuss/interview-question/6003635/WayFair-Automated-Parking-Lot-Problem-Design/ \ta. Repeat 1 : https://leetcode.com/discuss/interview-question/5965709/Wayfair-L2-reject \tb. Repeat 2 : https://leetcode.com/discuss/interview-question/5921100/Wayfair-or-L3-or-October \tc. Repeat 3 : https://leetcode.com/discuss/interview-question/5636472/Wayfair-Interview-Process-or-Questions 2. Hotel reservation platform...

We use a distributed worker platform to asynchronously process tasks (\u201Cunits of work\u201D) outside of the scope of a user request. A starting point for such a system could be...

I've recently received an invite for Tesla SWE new grad final onsite interview. I was wondering if anyone has information on this, or could share experience. They planned 5 one-on-one interviews: 3 co

We want to implement an in-memory tree key value store for Doordash Restaurant Menus. Definitions: - path is a / separate string describing the node. Example /Tres Potrillos/tacos/al_pastor - Values are all strings API...

Experience: 3 yrs 2 months Round 0: HackerRank test 2 questions had to be solved in 90 mins. 1st question was medium , 2nd was harder medium DP Round 1: Coding...

Status : Senior Software Engineer in non-faang Experience : 6.5+ Location : Bangalore Position : Software Engineer L3, Twilio Twilio OA Standard 2 questions that can be found online - one sliding window and one rest...

Karat Interview for Wayfair Introduction - 1 min System design - 20 mins Coding - 30 mins Introduction Tell me about your technical profile in a minute System Design The questions below are not in the exact...

Past work experience round Deep dive on one of the interesting projects I\'ve worked on. A detailed discussion on a production incident. # HLD round Design a food delivery system like Swiggy...

I’m designing a system to manage **Millions of unique, immutable text identifiers** and would appreciate feedback on scalability and cost optimisation. Here’s the anonymised scenario: **Core Requireme

I recently had an interview at wayfair for Software Engineer (L3) role, Round 1: Had hackerrank test which includes two question and mandatory to get atleast 75 marks. https://leetcode.com/discuss/interview-question/4491846/Wayfair-or-SDE2-L2-4-Onsite-Virtual-or-Coupon-category Round 2: LLD Round Design a...

Phone Screen - Modified LRU Cache - Implemented a working solution using map + pair data structure. Coding Round 1 [Hire] - Word Search in a List of Documents - Implemented a working...

Coding round 1 ---------------- you\'re given k v pairs funA: [\'int\',\'bool\'] funB: [\'int\',\'int\'] and queries like [\'int\',\'int\'] return all functions that match the description follow-up you\'re also given a flag is variadic funA: [\'int\',\'bool\'] , isVariadic: true funC: [\'int\',\'int\']...

Design Parking Lot (with API and DB schema design, SQL query was asked to count no of vehicles of currently parked in this parking lot) you have to design a...

Education: B.Tech CSE from NIT Position: SWE at PhonePe Location: Bengaluru Experience: 3.5 years Recrutier reached out to me via phone call and then rounds were scheduled. Round 1 : Machine coding round Experience : Hackkerrank...

**Intro** I'm about to start a project and I'd appreciate some input from the good people of Reddit. I'm not doing this by myself but I'm the most experience developer on the team which is why I'm req

Interview started with introduction, took approximately 5 mins. Next, there were five scenario based questions for system design which were allocated 20 minutes. I remember only 3 of them. 1....