hedera-harness-go
Harness for the Hedera ecosystem: an agent builds your dapp, hh checks it on chain in code
Demo
About
hh(hedera-harness-go) is a harness for the Hedera ecosystem, written in Go and inspired by hedera-dev/hedera-harness. You describe a dapp in one sentence and hh starts from scaffold-hbar with the official Hedera skills. The agent writes the contracts, deploy scripts and frontend, but it never holds a private key. After every attempt hh compiles, type checks and deploys to testnet with your connected wallet. It also runs YAML scenarios that make real transactions and check the result on the mirror node. Any failure goes back into the same agent conversation until everything passes. The same scenarios run on a built-in mock network in milliseconds, on a local Solo network, or on testnet.
How it's made
The whole thing is Go on top of hiero-sdk-go. Scenarios are strict YAML with actors, steps and assertions, checked offline with line numbers. There are 20 step types covering HTS tokens, NFTs, custom fees, airdrops, HCS topics and multisig schedules. Assertions are plain code that polls the mirror node REST API and verifies the HCS running hash chain. The hacky part is the mock network: it's a fake gRPC consensus node plus a fake mirror node running in the same process, so the real SDK client talks to it with no Docker. The agent loop drives the Claude CLI over stream-json and resumes the same session for repairs. Judge files are pinned by hash so the agent cant edit them to pass. The TUI is built from Charm libraries (bubbletea, lipgloss), the demos are recorded with VHS and releases ship with goreleaser.