Spawn is a DeSci launchpad for small computational models, deployed with real, checkable rules and funded by their own trading activity. A creator writes a model, a neural circuit built on a published connectome, a reaction-diffusion field, a coupled-oscillator system, or a similar dynamical system, and defines it formally as four parts: a state space, a step function, a seed, and a tick trigger. That specification is what lets anyone else independently recompute the model's current state and check it against a hash published on-chain. If the two don't match, that's a public, permanent falsification, not a dispute to be resolved privately. Launching also requires a structured provenance document before the transaction can even be submitted: what the model is not claiming to be, every dataset used with its origin and license, a real citation, and an explicit line between what came from real data and what the creator decided as an engineering choice. Vague disclaimers and placeholder text fail this step outright. The model launches with its own token in the same transaction that deploys it, records its provenance hashes, opens its trading pool, and locks its liquidity, atomically, with no separate step where any of it could be skipped. The liquidity lock isn't a timelock or an admin-controlled delay; the contract simply has no function capable of withdrawing it, for anyone. Trading fees on that pool fund the model's ongoing runtime: a share pays for the compute that keeps it stepping, a share goes to the creator, a fixed share supports the protocol. Holders can also provide liquidity to a model's pool and earn a share of its fees, which ties the model's continued existence directly to real trading activity rather than an arbitrary emissions schedule. When fees stop covering the cost of running, the model pauses, visibly and by design, not as a hidden failure, and can resume if funding returns. The result is a platform where two separate questions, is the science real, and is the money safe, are each answered by something enforceable in the code, not by a promise in the documentation.