The RISC Zero zkVM is a RISC-V virtual machine that produces zero-knowledge proofs of code it executes. By using the zkVM, a cryptographic receipt is produced which anyone can verify was produced by the zkVM's guest code. No additional information about the code execution (such as, for example, the inputs provided) is revealed by publishing the receipt.

In addition to our reference documentation on docs.rs, we have additional (non-reference) resources for using our zkVM that you may also find helpful, especially if you're new to the RISC Zero zkVM. These include:

• Our Factors tutorial, which walks you through writing your first zkVM project.
• The cargo risczero tool. It includes a new command which generates code for building and launching a zkVM guest and guidance on where projects most commonly modify host and guest code.
• The zkVM Rust examples directory, which contains various examples using our zkVM.
• This clip from our presentation at ZK Hack III gives an overview of the RISC Zero zkVM. Our YouTube channel has many more videos as well.
• We track zkVM issues with known workarounds using the rust guest workarounds GitHub tag. If you're having problems running your code in the zkVM, you can see if there's a workaround, and if you're using a workaround, you can track when it gets resolved to a permanent solution.
• And more on the RISC Zero website!

Crate Feature Flags

The following crate feature flags are available.

Note that in order to use risc0-zkvm in the guest, you must disable default features (set default-features=false).

| Feature | Target(s) | Implies | Description | | --- | --- | --- | ---- | | cuda || prove, std | Turns on CUDA GPU acceleration for the prover. Requires CUDA toolkit to be installed. | metal |macos|prove|Turns on Metal GPU acceleration for the prover profiler|all|--|Tracks where cycles are spent during guest execution as an aid to code optimization prove|all except rv32im|std| Disable this feature if you want to use the guest module in guest-side code std|all|--|Support for stdlib in the guest

• cuda
  • Optional (default is CPU only)
  • Turns on CUDA GPU acceleration for the prover
• metal
  • Optional (default is CPU only)
  • Turns on Metal GPU acceleration for the prover
  • Only available for MacOS
• profiler
  • Optional
  • Use with r0vm binary tool to profile guest code
  • Counts cycles during guest execution as an aid to code optimization
• prove
  • Enabled by default
  • Disable this feature if you want to use the guest module in guest-side code (or if you only need the verifier, for the sake of excluding unnecessary code)
  • Must be set when metal or cuda is selected
• std
  • Optional support for stdlib in the guest