arnaucube

Engineer with interest in cryptography and decentralization.

blog | other-notes

Some free time side projects:

go-snark-study: Go zkSNARK implementation from scratch (compiler, setup, prover, verifier)
go-bellman-verifier: Go Groth16 zkSNARK bellman proof verifier using cloudflare/bn256 Pairing
babyjubjub-rs: BabyJubJub elliptic curve implementation in Rust
poseidon-rs: Poseidon hash implementation in Rust
go-blindsecp256k1: Blind signatures over secp256k1 in Go (With the compatible Typescript implementation)
ring-signatures-rs: bLSAG ring signatures implementation in Rust
ipa-rs: modified Inner Product Argument (IPA) version from Halo paper in Rust using arkworks.
kzg-commitments: Kate-Zaverucha-Goldberg (KZG10) Polynomial Commitments in Go
go-dht: Kademlia DHT implementation in Go
merkletree-rs: Sparse MerkleTree implementation in Rust
go-merkletree: Sparse MerkleTree implementation in Go
shamirsecretsharing: Shamir's Secret Sharing Rust & Go implementation + WASM lib
kvartalo: a local social cryptocurrency for neigbourhoods, that we are using in a Barcelona neighbourhood as experiment. Build on top of Ethereum blockchain & Tendermint Core
go-chip8: CHIP-8 virtual machine emulator written in Go
chip8-rs: CHIP-8 virtual machine emulator written in Rust
fft-rs: Fast Fourier Transform (FFT) implementation in Rust
miksi: Ethereum zk-coin-mixer where all the computation & constructions are done offchain and then proved inside a zkSNARK to the smart-contract. (live demo on testnet)

More projects directly in github: https://github.com/arnaucube (Mirror of all the repos at: https://git.arnaucube.com).

Recent Work:

Vocdoni & Aragon (current) -

Decentralized governance & voting tooling.
Design and implementation of anonymous voting solutions using zkSNARKs. Introduced some design optimizations in the circuits which reduced the number of constraints.
Also, contributed to vocdoni/vocdoni-node adding zk related code.
Other stuff implemented:

vocdoni/keccak256-circom: ethereum sha3 (keccak256) hash function implemented in a Circom circuit
vocdoni/zk-census-proof: anonymous census proof circuit used in Vocdoni's Blockchain
vocdoni/arbo: optimized MerkleTree which parallelizes by CPUs for faster computation, compatible with circomlib implementation

OVOTE: Offchain Voting with Onchain Trustless Execution (kind of a zkRollup for voting)

OVOTE technical document
Forum post with a high level explanation.
aragonzkresearch/ovote: implementation of the OVOTE circuits, smart contracts & libs
aragonzkresearch/ovote-node: OVOTE backend node implemented in Go

Hermez zkRollup -

Decentralized zkRollup on Ethereum.
Main task has been to implement the Hermez node, used to launch the mainnet of the zkRollup network:
hermeznetwork/hermez-node
My focus has been mainly in the TxSelector, TxProcessor (managing the rollup state tree) and BatchBuilder (generating the data structure compatible with the zkSNARK circuits to do the proof generation).

iden3 -

Scalable decentralized identity system with privacy by design by using zero knowledge proofs.
Design and specify the core protocol, develop the core libraries, servers, smart contracts, zk circom circuits and zkSNARK Groth16 Go prover.

iden3/go-iden3-crypto: cryptographic primitives (SNARK-friendly) used in iden3
iden3/go-iden3-core: core implementation of the iden3 system
iden3/go-circom-prover-verifier: implementation of the Groth16 zkSNARK Prover and Verifier compatible with Circom
iden3/circuits: zkSNARK circuits used by the iden3 core protocol

blog - github - twitter