Halo2

Setup the Project

Fork the template, https://github.com/anudit/halo2-template. It simplifies the process of compiling Halo2 circuits in a highly customizable way.

Your project structure should look something like this.

• fib.rs contains a fibonacci circuit.
• lib.rs contains the customizable C glue to run your circuit.

Understand the C Glue

pub extern "C" fn compute(
  public_inputs: *const c_char
) -> *const c_char {}

This signature should remain constant otherwise zk-expo won't pickup the function. The compute function contains the functions you need to parse inputs and return valid json.

Build and Test

cargo +nightly build --target wasm32-unknown-unknown --release

Optimize the wasm file,

brew install binaryen
wasm-opt -Oz -o optimized.wasm ./target/wasm32-unknown-unknown/release/hello_wasm.wasm

On-chain Verification

• Your Solidity Verifier should be present in ``
• Tutorial on On-chain Verification

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