> For the complete documentation index, see [llms.txt](https://docs.iotex.io/llms.txt). Markdown versions of documentation pages are available by appending `.md` to page URLs; this page is available as [Markdown](https://docs.iotex.io/depin/iotex-depin-modules/w3bstream/build-with-w3bstream/on-chain-integration/verify-halo2-proofs.md).

# Verify Halo2 Proofs

<details>

<summary>Prerequisite</summary>

You must have built an Halo2 verifier executable. [-> Learn more here.](/depin/iotex-depin-modules/w3bstream/build-with-w3bstream/build-the-prover-code/halo2.md#build-the-prover)

</details>

## Generate the Verifier Contract

After the prover is built, a Solidity verifier contract can be generated with:

```sh
target/release/halo2-simple-circuit solidity -f ./verifier.sol

Generated verifier contract size: 8100
```

Just ensure you customize the `halo2-simple-circuit`  executable name with your own prover name.

## Example W3bstream Dapp (Halo2)

{% embed url="<https://github.com/iotexproject/w3bstream/blob/develop/examples/halo2-circuit/contracts/Halo2Dapp.sol>" %}


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