microworld.
OPEN SOURCE WORLD GENERATION

A whole world.
A little JSON.

Give it a seed. Get a world.
Terrain, biomes, and things to discover.
You bring the game.

Make yourself a world Read the docs
Deterministic by designNo keys. No accounts.
A SMALL WINDOW INTO SOMETHING BIG

Go on, explore.

Interactive playground
Customize this world Terrain & window

Changes apply when you generate. Add placement rules through the API ↗

Overworld/hello-world
Drag to explore · Scroll to zoom
Growing a little world…
Loading bundled world…128 × 128 cells · 16 × 16 chunks

Start with a ready-made world. Change the seed to make it yours.

SOMEWHERE TO START

Different worlds. Same little API.

Pick a preset. Bend the rules.
See where you end up.

LESS SETUP, MORE PLAY

Your world is
one request away.

A seed, a preset, a window. Get elevation, biomes, and placed objects as JSON. Render it however you like.

Get started
QUERY /api/world
curl --request QUERY \
  https://microworld.kaf.sh/api/world \
  --header 'Content-Type: application/json' \
  --data '{
    "seed": "hello-world",
    "preset": "overworld",
    "window": {
      "x": 0, "y": 0,
      "width": 128, "height": 128
    }
  }'
Your seed. Your coordinates. The same world, every time.

A world that stays put.

Request any window in any order. Versioned generation keeps terrain and placements consistent across chunk boundaries.

Make the rules.

Shape the terrain. Choose where things grow. Place structures with tile templates, spacing, and biome constraints.

Yours to build on.

A public API and stateless MCP endpoint. Apache 2.0 source. Store your changes, bring your renderer, make something fun.

WHAT WILL YOU MAKE?

Every good adventure
starts somewhere.

Start building Or help us grow Microworld ↗