Cryptographic key management and multi-chain transaction infrastructure.
I work at the layer most engineers abstract away — raw keys, raw transactions, raw signatures — across Bitcoin, EVM and Tron.
Named author of ERC-7208 · status Final
A standard that separates on-chain data storage from the logic that governs it, so tokenized assets stay interoperable across current and future token standards. I contributed from early Solidity test coverage through production contract work.
Keys and signatures
- EC key management and hierarchical derivation (BIP-32/44, SLIP-10)
- ECDSA and Schnorr signing, raw signature handling
- PSBT construction and multi-party signing coordination
- HSM-backed key lifecycle, multisig
Bitcoin
- Raw transaction construction and UTXO management
- Legacy, SegWit and Taproot output and spend types
- Nested SegWit → Taproot migration
EVM and smart contracts
- Account abstraction and EIP-7702 delegated execution with sponsored gas
- Ethereum signature standards — EIP-191, EIP-712, EIP-1271, and Safe encoding
- ERC-2771 meta-transactions, ERC-4626 vaults
- Proxies, Diamond, factories, deterministic deployment
- DEX and liquidity-aggregator contracts, Uniswap V4 hooks
- Cross-chain via LayerZero, plus a bridge built from scratch
Security
- Internal audits and third-party audits of external protocols
- Remediation cycles with external auditors
- Foundry (unit, fuzz, invariant), Slither
Solidity TypeScript Cairo
Foundry Hardhat Node.js NestJS PostgreSQL GraphQL Docker The Graph
Bitcoin EVM Tron Solana StarkNet Hyperledger Besu
LinkedIn · berbesidaniel@gmail.com
Open to remote contract work worldwide, and to relocation.