Software engineer working on systems programming, DeFi infrastructure, and application security. I build low-level, correctness-critical systems in Rust, Go, and Solidity, and I do offensive security research on the side.
Currently building payment terminal infrastructure at Verifone (ISO 8583, mutually authenticated TLS, signed software deployment) and reporting vulnerabilities on HackerOne.
Crossbook is a noncustodial hybrid DEX in Rust and Solidity. Traders sign EIP-712 orders offchain as gasless intents, a pure Rust matching engine crosses them, and an onchain settlement contract independently re-verifies every signature and limit before swapping atomically and netting to zero. Built with Alloy, axum, sqlx, and Foundry, and covered by property tests, fuzz and invariant suites, and a cross-language EIP-712 parity gate.
- Crossbook — hybrid DEX: offchain matching, onchain settlement, signed intents. Rust, Solidity.
- Assayer — noncustodial token safety scanner: forks live chain state, simulates a real buy → transfer → sell, and inspects bytecode to flag honeypots, taxes, and owner backdoors. Published to crates.io. Rust.
- JER Coin — a Bitcoin Core–based coin with custom network parameters and a freshly mined genesis, built and tested in CI. C++.
- Valley — an AI-aware desktop terminal built on a Rust and Tauri 2 native core with a React frontend. Rust, TypeScript.
Rust · Go · TypeScript · Solidity · C / C++ · PostgreSQL · Tokio · Foundry · Docker · Linux
Security: OWASP Top 10, web and API testing, threat modeling, Burp Suite, responsible disclosure.
Portfolio: jerusha.dev · jerushafrederick@gmail.com