Halo 2¶

URL: https://zcash.github.io/halo2/user/simple-example.html · GitHub: zcash/halo2

Description¶

A Rust library for building ZKP circuits using the PLONKish arithmetization with recursive proof composition (Halo). No trusted setup (uses IPA instead of KZG). Developed by ZCash. Hard to use — requires deep familiarity with PLONKish constraints. Notable deep-dive available from Trail of Bits.

Evaluation¶

Criterion	Value
Based on	UltraPLONK / PLONKish
Easiness	hard
Fast and short (<1s, <1MB)	probably
Post-quantum	no
Mobile and web	not found
Maintained	some activity on GitHub
Open source	yes — MIT / Apache-2.0
Security review	no
secp256k1 signature + sha256	SHA-256 yes, no signature verification

Notes¶

Quote from Halo document: "To create a proof of a statement, the prover will need to know the private inputs, and also intermediate values, called advice values, that are used by the circuit." (Uses "witness" to mean all values the prover supplies, including intermediates.)

Based on¶

PLONKish, PLONK

Resources¶

Docs: Halo2-Docs
Blog: a-deep-dive-into-axioms-halo2-circuits