javascript/Code

Conceptual knowledge and the ability to produce working code under time pressure are genuinely different skills, and this set is built around the second one. These are hands-on implementation problems — writing a debounce or throttle from scratch, implementing a deep clone, building a simple event emitter, or recreating a native method's behavior — the kind of task where understanding the concept in theory doesn't automatically mean you can produce correct, edge-case-aware code in 15 minutes.

What separates a strong answer here isn't just getting a working solution — it's how you get there. Talking through edge cases before coding (what happens with no arguments, with this, with async callbacks), choosing sensible variable names, and testing your own solution against a tricky case out loud all signal the same thing interviewers are actually screening for: how you think when the answer isn't already memorized.