Chargebee

Role: SDE 1

College: NIT (Batch 2019-2023)

Interview Date: January 2024 (Offer Date)

Interview Type: Full-Time

Result: Offer Accepted

Difficulty: Medium

Rounds: 5 rounds

Topics Asked: DSA, SQL, Aptitude, Language fundamentals (Java), CS fundamentals (SSL, HTTP vs HTTPS, memory allocation, garbage collector), System Design, DBMS (scaling, sharding, indexing), DNS resolution, CDN, Redis, Kafka, pseudo-code debugging, React basics, Projects, Behavioral/Managerial.

Experience:

This candidate, with 1 year of experience including an internship, received an SDE 1 offer from Chargebee in January 2024 and accepted it.

Round 1: Online Test (120 mins)

This round included 2 coding questions, 2 SQL questions, and 5 aptitude questions.

Round 2: Online Screening Round, Technical Interview (45 mins)

This was a screening round where the interviewer asked 1 easy DSA question and 1 easy SQL query. There was also a discussion about the candidate's current organization's work.

Round 3: Offline Technical Interview (2 hours)

Conducted by an engineering manager, this round involved medium-level DSA questions, 1 SQL query, and system design basics (like parking lots and chess). Topics included load balancing, scaling, and concurrency. The candidate was asked to design the High-Level Design (HLD) of a BookMyShow-like seat booking algorithm, focusing on concurrency. CS fundamentals, especially DBMS (scaling, sharding, indexing), DNS resolution, and CDN, were discussed. Questions on keywords from the resume, such as Redis and Kafka, were asked, including "How is Redis faster?" and comparisons of RAM vs. Disk vs. ROM vs. Cache. The interviewer also provided pseudo-codes to debug and fix edge cases. Frontend basics of React (DOM, lazy loading) were also covered.

Round 4: Offline Technical Interview (1 hour)

This round was taken by one of the directors of engineering. Questions covered basic language fundamentals (in-depth Java for this candidate), CS fundamentals (SSL, HTTP vs HTTPS, memory allocation, garbage collector), and one puzzle. Discussions included current organization's work and Chargebee's culture.

Round 5: Hiring Manager Round (1 hour)

Conducted by the Vice President, this round involved discussions around the candidate's resume, a few technical questions, work in the current organization, and general HR questions.