John Lee | Playground

Exploring by building.

Experiments, prototypes, and product ideas I use to sharpen product thinking through making.

Hand-drawn loop of idea, test, learn, and refine with the note test small, learn fast

Playground highlight

Now playing

Product Sprint.

Chrome Dino for product people. Jump over unclear specs, scope creep, P0 fires, and sync chairs, then chase your best score on the leaderboard.

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10 hazards
5 sprite states
Live leaderboard

Top score

Recent experiments

Build notes from things I shipped, broke, and learned from.

Jul 2026

Building Product Sprint

How an over-scoped “Ship It” prototype became a focused pixel-art runner about surviving product chaos—and used 82% of my Cursor model allowance along the way.

  • Next.js

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Jul 2026

Building my portfolio like a product

Designed, built, and shipped a personal portfolio using AI-assisted development—not as a static collection of work, but as a living product system.

  • Next.js

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Jul 2026

Prototype

SOXL market-monitoring agent

A scheduled AI agent that monitors a leveraged semiconductor ETF and delivers structured market updates through Telegram and WhatsApp.

  • Built in 1 week
  • Next.js

Read note →

Earlier builds

More experiments in the archive.

This is my lab.

Not everything here is polished. That's intentional. Ship, learn, and iterate.