Debugging and Developer Tools Questions

Proficiency using developer tooling and systematic debugging approaches to find and fix defects across client and server code. Topics include using browser developer tools such as the element inspector, console, network panel, and performance profiler; setting breakpoints and stepping through JavaScript code; reading and interpreting error messages and stack traces; using logging and log aggregation to trace server side issues; using debugger statements and watch expressions; reproducing bugs reliably and minimizing test cases; and applying performance profiling and memory analysis to diagnose regressions. Interviewers assess the candidate's process for isolating root cause, choosing appropriate tools, and validating fixes.