BrowserStack

Role: Software Engineer (Fresher)

College: Tier 3 College in Mumbai

Interview Date: Not Specified (experience updated Sep 2024)

Interview Type: Off-Campus (Referral)

Result: Selected (Implied by detailed HR round and positive tone)

Difficulty: Medium

Rounds: 6 rounds

Topics Asked: Data Structures, Algorithms, Low-Level Design, System Design, Operating Systems (Deadlock), DBMS, Networking (HTTP, HTTPS, HTTP Headers, Status Codes, User-Agent), Competitive Programming, Open Source, Projects, Behavioral Questions, MapReduce.

Experience:

The candidate was a final-year Computer Science student with competitive programming and open-source contributions. They were referred for a Software Engineer position.

Round 1: Online Round (HackerEarth)

• 2-hour coding test with 3 questions.
• 100 points: Design a reverse proxy with N servers and M endpoints. Requests go in round-robin. Handle server going down/up.
• 50 points: Given an array of numbers, return 1 if spirally sorted, else 0.
• The third question was not explicitly detailed in the snippet, but it was generally "Easy / Medium level".
• Scoring 120 points was considered, but the candidate scored 200.

Round 2: Machine Coding - 1 (Onsite)

• Problem Statement: Implement a log watching solution similar to tail -f for a remote, append-only log file.
• Server-side program to monitor and stream updates.
• Web-based client (e.g., http://localhost/log) to display last 10 lines on load and real-time updates without refresh.
• Constraints: Real-time updates, only send updates (not entire file), handle multiple clients, no page reload, no off-the-shelf tailing libraries. Focus on code quality, testability, modularity, corner cases.

Round 3: Machine Coding - 2 (Onsite)

• Problem Statement: Implement a simple stateless web service to interact with Google Chrome and Mozilla Firefox.
• Endpoints: /start?browser=chrome&url=http://example.com/ (start browser, open URL), /stop?browser= (stop browser), /cleanup?browser= (clean browsing session), /geturl?browser= (get active tab URL).

Round 4: Technical Round-1 with the Engineering Manager

• Favorite internship project discussion.
• Questions on a personal project: what if a change is made, how to handle it.
• Strengths and Weaknesses.
• Coding problem: Bring all zeros to the start of an array in O(n) time and O(1) space.
• Data Structure design problem: query everything in O(1) time.
• Huge file handling: count word occurrences in 1 TB file with 8 GB RAM (MapReduce algorithm was also mentioned in another similar fresher experience).

Round 5: Technical Round-2 with the Director of Engineering

• About projects, failed projects.
• HTTP vs HTTPS, HTTP error codes, User-Agent in HTTP header.
• Behavioral: What to do if asked to use C++ but prefer Python? How to solve a problem independently if manager is busy?
• System deployment considerations for production, types of logs for monitoring.
• "Walk me through your resume."
• "What one thing did you enjoy the most in the college?"
• "What do you do on weekends?"
• "What all parameters would you consider when you decide to use your piece of code into production environment?"
• "What are a few open source organisations you know or have contributed to?"
• "What is MapReduce algorithm?"
• "What is Deadlock? How to avoid it?"
• "How data has been stored inside DBMS?"
• "Why cannot private methods be overridden?"

Round 6: HR Interview

• "Explain work done at one internship."
• "How did you come to know about BrowserStack?"
• "Why BrowserStack?"
• "Do you use GitHub? Do you participate in Competitive Coding competitions?"
• "Anyone project you think you were failing but you envisaged and succeeded in it?"
• "How was your entire day?"
• "What do you think of our interview process?"
• "What is the value proposition of BrowserStack?"
• "How many contributions do you have on Github? Do you enjoy Open Source?"
• "What is your Codechef rating? Do you like competitive programming?"
• "Among the projects listed which is the most interesting project that you have done and why?"

Tips: BrowserStack focuses more on development skills than DSA (except for the online assessment). Machine coding is difficult and unique, so prepare beforehand. MapReduce algorithm is frequently asked.