Circom

ZK Email provides circuits and SDKs for proving facts about redacted email transcripts onchain. Useful when you want privacy-preserving identity or receipt checks without doxxing inboxes.

SP1 from Succinct is a zero-knowledge virtual machine that proves correct execution of RISC-V programs, and it is used to generate proofs for rollups and bridges. Teams compile a Rust program with it when a proof must stand in for re-executing that program onchain.

snarkjs is a JavaScript and CLI toolkit for generating and verifying zkSNARK proofs, and for running common proving workflows in Node.js and the browser.