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Debugging Dojo · Node.js

Observe. Hypothesize. Fix — JavaScript types, async, and API traps.

Progressive Node.js debugging: off-by-one and control-flow bugs, coercion and sort footguns, mutation during iteration, floating-point money, event-loop lost updates, this-binding, and prototype-chain object walks.

Learn with Ada, your AI coding mentor — ask questions or tap I’m stuck in any lesson for a nudge without spoilers.

Intermediate11 lessons~5.5h
First lesson free

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Course content

1 · Mindset

  • ○The Loop That Stopped EarlyFree12 min
  • 🔒The Else That Lied15 min
  • 🔒Sorted Like a Dictionary15 min

2 · Sharp edges

  • 🔒== Will Betray You18 min
  • 🔒sort() Without a Comparator15 min
  • 🔒splice During forEach20 min
  • 🔒Floating Point Is Not Money20 min

3 · Async

  • 🔒Forgot to Await the Promise20 min
  • 🔒Lost Updates on the Event Loop25 min
  • 🔒Detached Method Loses this22 min

4 · Boss

  • 🔒JSON.parse Inheritance Trap25 min