面接質問集 — ソフトウェアエンジニア 2026

エンドツーエンドのソフトウェアシステムを設計・構築・保守する。

よくある質問

1. 1. Implement a function that given an array returns the two indices whose values sum to a target. How do you optimize the time complexity?

   回答ガイド: Start with the quadratic version to show you understood the problem, then swap to a map to drop it to O(n). Discuss edge cases (duplicates, no solution).

2. 2. Describe the last tough code review you received. How did you process it and what changed in how you write code?

   回答ガイド: Show openness to feedback. Cite the specific observation, what you refactored and the habit you adopted to avoid the pattern going forward.

3. 3. Tell me about a critical production bug that you fixed. How did you isolate it, what tools did you use and what came out of the post-mortem?

   回答ガイド: Walk through detection (alerts, logs, metrics), the first hypothesis you validated and the safeguard you added so it cannot recur silently.

4. 4. When you have to choose between shipping speed and technical quality, how do you balance it?

   回答ガイド: Avoid the political answer. Give a concrete example with explicit trade-offs: business deadline, accumulated tech debt, risk of the change and why you yielded.

5. 5. Why are you interested in this role specifically and not another at similar seniority?

   回答ガイド: Connect three dots: what the company does, the technical problem that excites you and the skill you want to deepen over the next 12-18 months.