Ditto (SN118) Open-Sources Its Mining Stack Ahead of Launch

Ditto (SN118) disclosed that it has open-sourced its agent and memory harness alongside a self-contained DittoBench starter kit. The release gives miners a way to practice locally before on-chain mining goes live on the subnet (SN118) by the end of June, 2026.

The same harness is what production will migrate to on the same timeline, which means anyone optimizing against the kit today is working with the exact pipeline the on-chain validator will use to score submissions. The window between today and the launch is the practice window.

What Just Shipped

Ditto open-sourced two pieces, both built to get miners ready for Subnet 118:

1. THE AGENT HARNESS

Ditto’s full agent and memory stack, now publicly available. Miners can run the entire system locally with a single binary, with no external services to wire up. It is dual-licensed, with an open-source license for the community and a separate commercial license for partners who need different terms.

2. THE DITTOBENCH STARTER KIT

A self-contained practice environment that runs the same scoring loop the on-chain validator will use. It comes with a bundled seed user, a playground UI for testing the agent in real time, and built-in scoring modes that show miners exactly how their changes affect performance.

The starter kit is where miners do their optimization. Everything a miner would want to tune (model choice, prompts, retrieval settings, tools) sits in a single file marked with extension points. Local scoring is free and runs quickly. The hosted validator, once live, will rotate fresh randomized datasets per submission so nothing can be overfit.

The on-chain piece comes next. Production migrates to the open-sourced harness by the end of the month, and the on-chain mining mechanism activates on SN118 at the same time. Validators will score signed miner submissions and emit rewards. The local practice loop and the on-chain scoring loop are the same loop, which is the part that makes this release different from most subnet launches.

Until Mining Goes Live

The practical question for anyone considering mining SN118 is whether the kit is worth opening today versus waiting until the on-chain mechanism activates. The on-chain validator will score against the same harness that’s now public, so miners who start optimizing today are tuning against the actual production pipeline rather than a stand-in. 

Miners who wait are skipping the only practice window they get before submissions are live and competitive. Ditto’s open-sourcing is, in effect, a head start. Whether anyone takes it is the next two weeks of activity.