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Ravino Juwono

Work

Things you can use, not just read about.

Each of these is a real program with its own page and notes on how it is built. They are small on purpose and made to be poked at.

Five bodies and their trails in the N-body lab, with the energy drift readout
2026Playground

Orbits

A gravitational N-body lab. Change the integrator and watch the energy drift, or fail to.

  • TypeScript
  • React Three Fiber
  • Velocity Verlet
Open
Two double pendulums, teal and amber, with their trails and the divergence strip
2026Playground

Double pendulum

Two pendulums released a thousandth of a radian apart, and how quickly they stop agreeing.

  • TypeScript
  • Canvas
  • Runge–Kutta 4
Open
The shift board: a week of shifts with issues listed beside it
2026Playground

Shift

Drop shifts on a week. It flags overlaps and coverage gaps as you go and exports the result as a calendar.

  • TypeScript
  • Constraint checks
  • iCal export
Open
The shared globe with lights standing at countries
2026Live

Hello from

Leave a light on the globe from wherever you are. Country only, nothing else is kept.

  • Next.js
  • Neon Postgres
  • React Three Fiber
Open
The front page of this site: the Earth beside the name
2026Live

This site

A scroll-driven film in React Three Fiber on a static Next.js shell, with a real Earth in it.

  • Next.js
  • React Three Fiber
  • GSAP
Open