About this site — Xahmoeba

What it is, and is not

Xahmoeba is a small artificial-life experiment: a species of digital creatures whose bodies grow from a 32-byte genome through a fixed developmental process, who inherit from two parents, and who live as one population with a public lineage. The ledger is the infrastructure that keeps that population honest — who keeps which moeba, who its parents were, what chance decided at its birth — not the idea itself.

Technically it is a protocol on Xahau: one issuing account with hooks that admit breeding requests, fix each birth’s randomness from a ledger that closes after the parents are chosen, compute the child and mint it. This site is one way of looking at the result. It does not decide anything. If the site and the ledger disagree, the ledger is right and the site has a bug. The whole design, including what the species’ account can and cannot do and why it is not blackholed, is written up in the whitepaper.

What this site does with your moebas, and does not

Every action a keeper can take — selling, giving, naming, opening a moeba to breeding, breeding, burning — is a button on the moeba's page once the site knows which account is yours. The site builds the transaction and lays it out, field by field and as JSON, for you to sign with whatever wallet holds your key; Xahau does not care which. It never holds a key and it never submits on your behalf. If you use Xaman, you can connect it so the request opens in that app directly, and the site then reads the result back from the ledger and tells you what the Hooks said.

Where the idea comes from

Xahmoeba does not come out of nothing, and does not claim to. Growing complex shapes from small sets of rules goes back to Aristid Lindenmayer’s work on plant growth in the 1960s. Richard Dawkins’ biomorphs (1986) showed that a genome can generate a shape and that a person can breed shapes by choosing among offspring. Karl Sims’ Evolving Virtual Creatures (1994) is the closest ancestor: genetic instructions that describe a developmental process, interpreted into a body and its control, with mutation and crossover changing structure and not only parameters. Since 2017, projects such as CryptoKitties, Heterosis and Arborithms have made digital heredity ownable, persistent and breedable on a blockchain, each in its own way.

1968LindenmayerSimple rules can grow complex biological structures.
1986Dawkins’ biomorphsA genome can generate a shape, and a person can breed shapes by choosing.
1994Karl SimsDigital creatures can develop bodies and behaviour from evolving genetic instructions.
2017–CryptoKitties, Heterosis, ArborithmsDigital heredity becomes ownable, persistent and breedable on a blockchain.
nowXahmoebaDevelopmental heredity, public lineage, emergent rarity and individual keepers, together in one evolving population.

What Xahmoeba adds is a particular combination. The genome is neither a seed for an image generator nor a list of visual traits; it is read through developmental steps that build one canonical body, and the renderer only visualises that body afterwards. Because of that, a child resembles its parents for reasons that can be traced gene by gene. Variation is settled once, at birth, from chance the network supplies after the parents are committed, and is inherited from then on. Nothing is marked rare in advance: a look is rare when the genetics make it hard to reach. And the founders are only the beginning — the work is the population and what its generations do, kept by many people rather than run inside one simulation.

Where the data comes from

From the ledger, and nowhere else. Every moeba is a token minted by the species’ account; the site reads its history and each token's current state from a Xahau node, and draws the animal from the genome on your device. Between visits it only reads what has happened since. This copy has a small server in front of the node, an indexer, that does the same read once for everyone and answers in a moment; it holds nothing the ledger does not, and if it is down your browser reads the node itself. Keeper tools prepare transactions for your own wallet to sign; nothing you sign passes through anyone in between.

Check anything yourself

Every moeba page shows the records the claims rest on, and the site re-does the arithmetic in front of you:

Replay. A birth is a pure function of the two parents' genomes and the recorded randomness. The moeba page runs it again on your device and says whether the recorded genome matches.
Randomness. The record names the ledger of the draw: the ledger’s own random number, drawn on the fire that captured the birth, after its parents were sealed. That fire’s metadata is public, and the draw can be checked from it. See where the randomness comes from.
Ownership and offers. Every token id links to the explorer, where the token's current keeper, sell offer and full transaction history are shown by a third party.
The hooks' hashes. They are on the species’ account, and every version that has run is on the ledger with the ledger it went live in. The source is not published. The check you can make is the replay above: this site runs the birth again from the records on the token.

This copy

A rehearsal. This copy reads a species running on the Xahau test network before its release. The population may be wiped, the issuing account replaced and the rules changed without notice, and nothing born here carries over to the release. The whitepaper says why it is done in public.

Network: Xahau testnet
Species’ account: rMmx5nHzoVJAoMTFWkgCCMrZryTaD682tr
LIFE account: rGXvnPHRDktpq8BQYkKVz8AiByy3Q4BTDy Its hooks keep each living moeba's life: its needs, its rests and visits, and the care its keeper signs. It is not the species’ account, so a moeba’s token and genome are beyond it. How life works.
Node: https://xahau-test.net
History from: ledger 12,545,963
Run by: xrplorer ApS — see the terms and the privacy notice

Words used here

One word for each idea, used the same way on every page. Where genetics has its own word for it, that is given too.

moeba, moebas: One creature, several creatures. The species is Xahmoeba.
keeper: Whoever holds a moeba, shown by their full address — the address is who they are here. The ledger calls it the owner. “You”, when it is yours.
founder: A moeba born with no parents, from ledger randomness alone: generation 0. A tag such as “1 in 3,900 founders” says how often a new founder shows that name. In genetics: founder (as in the founder effect).
trait: One characteristic you can see or measure: body plan, limbs, body size. Some traits are a kind (legs, fins); others are a number, where both copies add up.
gene: The place in the genome that holds a trait. Every moeba has two copies of each gene. In genetics: gene, locus.
variant: One way a gene can be: elongate, compact, fins. In genetics: allele.
copy 1, copy 2: The two copies of every gene. A child gets one copy of each gene from each parent. In genetics: the two chromosomes of a pair.
shows, hides: When the two copies differ, the variant higher on the ladder shows and the other hides. A hidden variant can still be passed on, and show in a child. In genetics: dominant, recessive.
carries, carrier: Has the variant on at least one copy, shown or hidden. In genetics: carrier (heterozygous, when the copies differ).
name: Read from four traits: body plan and limbs give the first word, symmetry and pattern the second. Moebas with one name can differ in everything else. In genetics: morph.
a first: The first moeba recorded with a name.
mutation, mutation route, only by mutation: A small chance at each birth that a variant changes into another. A route says from which variant, and when. Some variants come only by mutation: no founder is born with them. In genetics: mutation (a new one is de novo).
breed, a birth, a pair: You breed a pair of moebas; what comes of it is a birth.
ready to breed: Mature, with births left, and not waiting for a child.
open to breeding: Its keeper lets anyone breed with it, at the price they set. The Protocol calls this standing statement its terms.
births left: How many more births a moeba can be a parent in. Fixed at its own birth; spent one at a time.
at risk: A variant that five or fewer living moebas can still pass on: they carry it and have births left. Moebas do not die, but their births run out, and a variant nobody can pass on reaches no more children.
the Hooks, the species’ account: The one Xahau account that mints every moeba (the Protocol calls it the issuer), and the code on it that runs every birth: it admits requests, takes the fees and writes the records. Nobody signs for it; the Hooks wake themselves up.
fire: One wake-up of the Hooks by Xahau’s Cron. Each fire moves one birth one step, and is paid from that birth’s budget.
ledger 12,545,999: Xahau writes a new page of its shared record every few seconds, and numbers each one. A ledger number is a time, stamped by the network.