Interview Experience - Pinterest

Overview

This interview experience details the hiring process for a Senior Software Engineer position at Pinterest's Switzerland office. The candidate progressed through a comprehensive multi-round interview process that included HR screening, technical assessments, system design sessions, and a competency evaluation. Despite receiving positive feedback on all technical components, the final outcome was a rejection based on insufficient signals from the competency interview.

Pinterest, known for its image-sharing and discovery platform, conducts thorough technical interviews that assess both engineering skills and cultural fit. This experience provides valuable insights into what candidates can expect when interviewing for senior engineering roles at major tech companies, particularly the increasing emphasis on behavioural and competency assessments alongside technical proficiency.

Interview Process

The interview process at Pinterest was structured across two distinct loops, each containing multiple assessment stages:

Loop 1:

• Initial HR screening call
• Graph-based algorithm problem

Loop 2:

• Two system design rounds
• Two coding rounds
• One competency interview

The HR representative provided feedback throughout the process, notably communicating that the initial graph problem received "excellent" feedback, and both system design rounds received "great" feedback. The company even sent an encouraging email mid-loop, stating: "Your feedback on both system design rounds is great! Keep on doing the same for the next rounds."

The entire process demonstrated Pinterest's commitment to a comprehensive evaluation, though the outcome highlighted an important lesson: strong technical performance does not guarantee an offer when other assessment areas are involved.

Technical Rounds

HR Screening and Graph Problem

The first technical interaction combined an HR screening call with a graph-based algorithm problem. This approach allowed the company to assess both communication skills and foundational computer science knowledge early in the process.

Graph problems are a staple in technical interviews, testing a candidate's understanding of:

• Graph traversal algorithms (BFS, DFS)
• Shortest path algorithms
• Connected components detection
• Topological sorting
• Cycle detection

The candidate performed well on this assessment, with HR explicitly stating the feedback was "excellent." For senior engineering roles, this initial screen serves to verify that candidates possess the algorithmic thinking expected at their level.