Software Engineer

Job Title: Software Engineer Department: Engineering & Product Development Reports to: Engineering Lead Location: Flexible

You'll own Codex's financial partner integrations end-to-end — from API contract and webhook design through to reconciliation and production hardening — and build the automation layer that makes our trading and treasury operations increasingly self-running.

This is a high-ownership role at the infrastructure layer of the business. You'll be adding new payment rails, eliminating manual operational workflows, and designing systems that handle real money reliably across fiat and crypto rails. You'll work directly with the founders and Engineering & Product Development team, and closely with Compliance, Operations, and Financial Partnerships.

• 6 to 10+ years of backend engineering experience in cross-border payments, stablecoins, FX infrastructure, or crypto custody (Senior profiles are also considered favourably)
• Production experience with both crypto rails (on-chain settlement on major networks like Ethereum, Tron and Solana; bridging major stablecoins; DeFi protocols) and fiat rails (SWIFT, SEPA, local schemes such as FPS or CHATS)