10-react-timer

10 — React Timer

A timer app demonstrating MobX computed values and side effect management with React.

Concepts

• observer — re-renders when secondsElapsed or isRunning changes
• Computed formatting — formatted getter converts seconds to MM:SS
• Side effects — setInterval managed by the store, cleaned up via useEffect on unmount
• Non-observable fields — intervalId is excluded from MobX tracking

Run locally

npm install
npm run dev

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