Backend and protocol engineer in Berlin. I work in Go and Rust on distributed systems and blockchain protocols, and these days mostly on zero-knowledge proof systems.

I'm open to senior engineering roles.

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Rust OpenVM Plonky3 RISC-V

A Poseidon2 extension for the OpenVM zkVM.

Without it, a guest program that needs Poseidon2 has to build the hash out of RISC-V arithmetic: thousands of instructions, each one proved. With it, one permutation is one custom instruction.

• Instruction: PERMUTE permutes a 16-word state in memory, in place.
• Circuit: a permute chip reads and writes the state, and a periphery chip proves the output is the permutation of the input. Both are AIRs over BabyBear, connected by a lookup bus.
• Guest library: a sponge hasher plus hash_u32s, hash_bytes and the raw permute.
• Example: builds, executes, proves and verifies a guest program through the SDK.

It is still in development and has not been audited.

• ethereum/go-ethereum#27845 (Go). Added state overrides to eth_estimateGas in Geth, so a caller can estimate gas against modified balances, code and storage.
• safe-global/safe-modules-deployments#150 (TypeScript). Added the Social Recovery Module deployment on Arbitrum One.
• zarbanio/subgraph. (TypeScript) The subgraph for the Zarban stablecoin protocol.
• SOFIE-project/Marketplace (Solidity, Python). Ethereum smart contracts and a web3 client for an on-chain marketplace, written at Aalto University.

• paxos (Python). An implementation of the Paxos consensus algorithm.

• Delivery Hero: display ad server
• Talon.One (acquired by Adyen): promotion engine
• Zarban: stablecoin protocol, as founding engineer
• Snapp: real-time messaging
• Aalto University: SOFIE project

The details are on my website.