LinkedIn Software Engineer Interview Questions

1.Tell me about a time you gave someone feedback that was hard to hear. What was the feedback and how did they react?

2.Describe a time you took ownership of a problem that wasn't technically your responsibility. What was the problem and how did you handle it?

3.Tell me about a time you pushed back on a product feature or requirement because you felt it wouldn't serve users well. What was the feature and how did you handle the pushback?

4.Walk me through a time you raised the engineering bar on your team. What standards were you trying to improve and how did you drive the change?

5.Describe a time you had to work with someone difficult to get something shipped. Who was this person, what made them difficult, and how did you build the relationship?

6.Tell me about a technical bet you made that didn't pan out. What was the decision, why did it fail, and what did you learn?

7.You need to build a search feature for LinkedIn Recruiter that finds candidates based on skills, location, and experience. How would you structure the data and implement the search functionality?

8.Write a function that merges two sorted arrays representing LinkedIn connection lists, where each array contains user IDs in ascending order. Return the merged list without duplicates.

9.You're building a feature for LinkedIn Feed that requires real-time updates when a user's connections post new content. How would you design this system to handle LinkedIn's scale of hundreds of millions of users?

10.LinkedIn uses trunk-based development with continuous deployment. You've written code that passes all tests locally but breaks the canary deployment at 1% traffic. How would you debug this issue?

11.Walk me through how you'd implement a rate limiter for LinkedIn's API that serves both our mobile app and third-party developers. What algorithms would you use and how would you handle different client types?

12.LinkedIn Jobs needs to send millions of job recommendation emails daily. The current system is taking 6 hours to process, but product wants to reduce this to under 1 hour. How would you approach this optimization?

13.Design the backend system for LinkedIn Learning's video streaming service. Users watch thousands of courses simultaneously, and we need to optimize for global delivery while tracking detailed progress analytics.

14.You're tasked with building LinkedIn's professional event recommendation system. It needs to suggest relevant virtual and in-person events to members based on their industry, connections' attendance, and career interests.

15.Design a system that allows LinkedIn members to collaborate on posts before publishing. Multiple people need to edit, review, and approve content in real-time, similar to Google Docs but optimized for professional content creation.

16.Build a fraud detection system for LinkedIn Recruiter that identifies fake job postings and suspicious recruiter behavior in real-time. The system needs to protect both job seekers and legitimate recruiters while minimizing false positives.

17.Design the infrastructure for LinkedIn's A/B testing platform that needs to serve experiment assignments to billions of requests per day while maintaining statistical validity and allowing for complex targeting criteria.

18.Design a system that personalizes LinkedIn Sales Navigator's prospect recommendations for each sales rep based on their territory, industry focus, past outreach success, and current deal pipeline. The system needs to refresh recommendations as market conditions and rep performance change.

19.Tell me about a time you mentored a junior engineer or intern through a challenging technical problem. What was your approach?

20.Tell me about a time you had to deliver difficult news to stakeholders about a project timeline or technical limitation. How did you handle that conversation?

21.Tell me about a time you had to influence a more senior engineer or tech lead to change their technical approach. What was at stake and how did you navigate that conversation?

22.Walk me through a time you convinced your team to adopt a new technology or practice that you believed would improve our engineering quality. How did you drive that change?

23.Describe a time you had to get multiple teams aligned on a technical decision when they had competing priorities. How did you build consensus?

24.Describe a situation where you had to make a judgment call about member privacy or data handling when the product requirements were unclear. How did you approach that decision?

25.LinkedIn Feed serves billions of impressions daily, but our machine learning model latency increased by 50ms during peak hours. Estimate the business impact if we don't fix this within a month.

26.LinkedIn wants to estimate the potential member engagement impact of adding voice messages to our messaging platform. How would you size this opportunity and what key assumptions would drive your analysis?

27.Sales Navigator's lead generation feature isn't performing well in our European markets compared to North America. Walk me through how you'd diagnose what's causing the performance gap.

28.If LinkedIn Learning wanted to expand into live instructor-led training sessions, estimate how many concurrent sessions we could support with our current video infrastructure before hitting capacity limits.

29.LinkedIn's weekly active user growth rate dropped from 3% to 1.5% month-over-month across all regions. No major product changes shipped and there were no outages. How would you approach investigating this decline?

30.A LinkedIn Recruiter client complains that our candidate search results have become less relevant over the past month. No search algorithm changes were deployed. Estimate how you'd quantify and investigate this relevance decline.