October 20, 2026·5 min read
Ask an engineer how they spend their week and almost none of them say "writing new code on a blank page." They say reading logs, reproducing a report, bisecting a regression, and untangling something a former teammate left behind.
Then we interview them by asking them to write new code on a blank page.
Debugging is the skill that actually predicts day-to-day performance, and it is the one most interviews never measure.
A from-scratch coding problem rewards recall and speed. It tells you whether someone can produce a known algorithm under pressure.
It tells you almost nothing about:
Those are the behaviors that decide whether a hire is productive or dangerous in a real codebase.
The cleanest way to assess debugging is to hand the candidate a small system that runs but misbehaves, and watch them fix it.
Good broken scenarios share a few traits:
A failing test suite, a service that returns the wrong number, a page that loses state on refresh: all of these force the candidate to read, reproduce, and reason.
The fix matters less than the path to it. Watch how they:
A candidate who says "let me reproduce it, then check the assumption in this function" is showing you exactly how they will behave on your on-call rotation.
Judging debugging from a shared document is hard, because the interesting part is the process, not the final file.
EasyEnv runs the candidate in a real environment with an intentionally broken service, and records the session. You see the terminal, the edits, and the order they happened in. The audit trail turns a fuzzy "they seemed to struggle" into a concrete record of how they diagnosed the problem.
Writing code from scratch is a baseline skill. Fixing code you did not write, under uncertainty, is the job.
Interview for the job.
Run live coding sessions and take-home challenges in real production environments. Watch sessions back, score consistently, and hire with confidence.
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