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Jack & Jill·San Francisco, United States·onsite

Senior Full-Stack Engineer (+ Equity) at SYSTM

Posted 1 month ago
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Ruby on RailsReactTypeScript

About the role

What you'll do

  • Lead the technical architecture of a fintech platform revolutionizing cross-border stablecoin finance.
  • Build multi-currency wallets, stablecoin on/off ramps, and yield optimization using Stellar and USDC rails.
  • Develop an AI-powered Agentic CFO layer with LLM-driven financial intelligence and autonomous actions.
  • Create a high-performance React/TypeScript merchant dashboard and robust Node.js/Python backend services.
  • Make all build-vs-buy decisions and shape the engineering culture as the primary technical leader.

What you should know

  • This is a high-impact role as the first senior engineer with significant equity (1-5%) in a pre-seed startup.
  • Requires entrepreneurial mindset and experience owning complex fintech or blockchain product architectures.
  • Opportunity to work directly with a founder and influence product direction and engineering culture from the ground up.
  • Role demands expertise in production-grade AI/LLM features including agentic workflows and prompt engineering.
  • Work onsite in London, UK, with exposure to cutting-edge fintech, blockchain, and AI technologies.

About the company

  • SYSTM is a VC-backed fintech startup focused on building a stablecoin financial operating system.
  • Founded by Jasper Tay, ex-Co-Founder & COO of Plutus, with deep regulated fintech expertise.
  • Company is at a pre-seed stage with 25+ signed design partners and plans for global scale.
  • Unique focus on integrating blockchain (Stellar), stablecoins (USDC), and autonomous AI for treasury management.
  • Culture values entrepreneurial leadership, innovation at the intersection of finance and AI, and early team ownership.

Key required skills

ReactTypeScriptNode.jsPythonStellar - blockchainUSDC - stablecoinLLMAIAgentic workflows

Summary generated from the original posting.