Software Engineer · Phone Screen · Coding, System Design

OpenAI — Software Engineer ❌ Failed

Level: Staff-Level

Round: Phone Screen · Type: Coding, System Design · Difficulty: 6/10 · Duration: 60 min · Interviewer: Unfriendly

Topics: Language Design, Primitives, Generics, Tuples, Type Inference, Crossword Puzzle Solver, Brute Force Algorithm

Location: San Francisco Bay Area

Interview date: 2026-01-30

Got offer: False

Summary

I had a coding round and a system design round.

Details

In the coding round, I was asked to work with a toy language. The language included primitives (char, int, float), generics (like T1, T2), and tuples (containing primitives, generics, or other tuples). My tasks were:

1. Implement a Node class to represent primitives and tuples.
2. Implement a toString function for the Node class.
3. Implement an infer_return function, which takes inputs like T1 and T2 and determines their corresponding types, raising an error if conflicts are found.

I had previously encountered a similar question, so I didn't have many issues during the coding part.

For the system design round, I was asked to design a system to solve crossword puzzles, given a board and a dictionary as input. I struggled with this question and ended up suggesting a brute-force solution.