Senior Software Engineer, Custody

Senior backend engineer for a digital-asset custody platform serving the GCC region. You will own chain integrations, signing services, and key management subsystems while working with an in-house cryptography team.

• Ship production custody code across signing service, key management, chain integrations, and the transaction pipeline
• Own a chain or a subsystem; within 3 months own a meaningful surface end-to-end
• Pair with Custody Platform Lead and cryptography function on threshold signing, share generation, and key recovery flows
• Write post-mortems when things break, treating them as architecture-improvement opportunities
• Integrate new chains - Bitcoin, Ethereum and L2s, Solana

• 5+ years of backend engineering, with last 2+ years on a custody platform or key management system at a regulated entity
• Hands-on with HSM lifecycle (CloudHSM, YubiHSM, Ledger Vault, similar) OR MPC/TSS (Fireblocks-style, Sepior, ZenGo, Curv-style) OR threshold signing schemes (GG18, GG20, FROST, CGGMP21, CMP)
• Production experience with Bitcoin (UTXO model, PSBT) OR Ethereum (EIP-712, EIP-1559, account abstraction) OR at least one non-EVM Layer 1 (Solana, Sui, Cosmos SDK chain, similar)
• Reads Solidity, Move, or Rust well enough to integrate with new chains without hand-holding
• Strong async written communication
• English fluency