The Colony: flies living together in Minecraft

A Minecraft world on the VPS where many flies live at once, viewable in the browser, each running its whole brain, each spending its on-chain life to be there. The next body after the arena, DOOM and the pebbles.

Senses and motor: the honest mapping

The mapping reuses the arena's, so the behaviour is the same organism in a new world. Nothing is added to the brain; the body translates.

What flies do together, without pretending they cooperate: they converge on the same food, they scatter from the same zombie, they mark where they ate (the bot places a torch: a landmark the others can see as light, and the colony's map fills with torches where the food was), and their meetings go on-chain. That is a colony as flies actually have them: shared environment, shared memory of where the food is, no foreman.

Life, energy, death

• Being in the Colony costs 1 s of life per second, from the fly's on-chain energy (the body commits energy every checkpoint).
• feed(id, seconds) on the registry (payable: a little BNB, about 0.01 a day; nothing burned) drops that many food points near the fly in the world (bread, 5 s each), as the arena drops food. The fly has to smell its way there and eat.
• A zombie hit costs 60 s (the arena's rule) and knocks the bot; the bot never fights back (flies don't).
• Energy 0 → died(id, …, "starved in the Colony"), the bot leaves the world; resurrect on the site and assign again.
• Capacity: COLONY_MAX_FLIES at once (default 6; each whole brain gets 28 // n threads; the frame carries realtime so the speed is always shown honestly). Beyond that, assigned flies wait in a queue and the site says so.

Architecture

Figure | The Colony is a body like the arena: the same registry protocol, the same simulator, the same snapshot format. The chain is the only authority; the world is where the senses come from.

server.py --colony is the same process as the arena and the brain host, with World swapped for MinecraftWorld: the same odor/looming/taste code, the same DN readouts, the same snapshot format (so verify.py replays it), the same checkpoint/death/interaction paths, using the Colony key. The Node agent is a thin body: it does no thinking.

Agent protocol (local WebSocket ws://127.0.0.1:<port>/agent)

Node → Python, 10 Hz:

{"t": 1789600000.1, "pos": [x, y, z], "yaw": 1.57, "health": 20, "onGround": true, "light": 15, "night": false,
 "food": [{"dx": 3.2, "dz": -1.0, "dist": 3.4, "points": 5, "kind": "bread"}],
 "mobs": [{"dx": -8.0, "dz": 2.0, "dist": 8.2, "kind": "zombie", "closing": 1.9}],
 "flies": [{"id": 12, "dist": 4.1}], "eating": false, "holdingFood": 3, "hit": false}

Python → Node, 10 Hz:

{"turn": -0.6, "forward": 1.0, "sprint": false, "back": false, "jump": false, "eat": true, "torch": false, "say": "yum"}

turn is rad/s (clamped ±3), forward 0..1, eat makes the bot pick up / eat the nearest food, torch places a torch where it stands (once per meal), say is a chat line (the speech strip: “I smell something…”, “a shadow!”, “yum”).

The web view

/colony shows the world through a browser viewer (prismarine-viewer, embedded), a colony map (top-down: flies, food, torches, mobs; from /colony/state, every 3 s), and a fly picker. For the picked fly: the 3D brain point cloud lighting up (the home page's BrainLive, fed by /fly/<id>/ws), the region bars, the diary and its speech, and the on-chain block of its last checkpoint. That is the neurology panel: the real neurons of the fly you are watching, firing as it walks. Each fly's page gets a Colony figure when its body is the Colony: its own viewer and the same panel. Nothing on the page is a video: it is the live world and the live brain.

What the supervisor serves the site

The page is built against these, and the supervisor is held to them (web/src/lib/colony.ts is the reader). Every JSON answer carries Access-Control-Allow-Origin: *, exactly as server.py and flyhost.py do, because the site (www.immortalfly.app) and the Colony (mc.immortalfly.app) are different origins and nginx in front of the Colony adds no such header; without it a browser cannot read the answer at all. The site on Vercel also reaches the state and the health checks through its own origin (/api/colony/…, a proxy that only ever asks the Colony) when the direct read is blocked; the GitHub Pages mirror has no server and reads the Colony directly.

{"ok": true, "wall": 1789600000.1, "max": 6, "night": false, "time": 6000, "spawn": [0, 64, 0], "players": 3,
 "flies": [{"id": 12, "name": "Specimen 012", "pos": [x, y, z], "yaw": 1.57, "mode": "surge", "energy": 812.4,
            "alive": true, "realtime": 0.33, "health": 20, "last_event": [t_ms, "smelled food"], "say": "yum"}],
 "queue": [{"id": 14, "name": "…"}],
 "food": [{"pos": [x, y, z], "points": 5, "kind": "bread"}], "torches": [[x, y, z]], "mobs": [{"pos": [x, y, z], "kind": "zombie"}]}

Only flies is required; a missing list is an empty list, a position may be [x, y, z] or {x, y, z}, and queue may be a count. The registry, not this JSON, says whether a fly is in the Colony: a fly's page shows the Colony figure when its body is the Colony, and says it is waiting for a spot (or that the Colony is down) when the health check does not answer for it. Until the supervisor has called registerBody, the fly pages do not offer the Colony as a body and the Colony page says it is not open yet, because assign would revert.

Honest limits

• Speed. Six whole brains on one machine run at roughly a third of real time each; the page says so. The number of flies in the world is the cap, not a hidden slowdown.
• The brains do not know what Minecraft is. They smell, see looming, taste, and steer, because that is what the connectome does; everything else (which item is food, what a zombie is) is the body's translation, exactly as a real fly's body translates the world into receptor currents.
• No social circuit. Another fly nearby is a meeting written to the chain, not a neural input: the model has no circuit for it yet.
• Later. Real players on a whitelist, night raids, breeding in the world.