Senior/Staff Software Engineer, Product

About Slash

Started in 2021, Slash is one of the fastest growing fintechs in the world and we power over ten billion dollars a year in business purchasing across numerous industries. We recently raised a $100M Series C led by Ribbit Capital with participation from Khosla Ventures, Goodwater Capital, NEA, and Y Combinator, accelerating our expansion into new markets and products.

Slash is headquartered in San Francisco, and has a strong in-person culture.

About the role

Slash is, at its core, a technology company and is on a mission to build the best engineering team in the world. We’re looking for a Senior/Staff Software Engineer to help build and evolve our core banking product that powers $10b in transaction volume a year. This role blends infrastructure-level thinking with deep product intuition. You’ll build fault-tolerant, user-facing financial primitives that spans across all customers, and you’ll do it fast, cleanly, and with ownership.

What you’ll do

• Own and ship entire product surfaces end-to-end, from database schema and API design to building the product customers interact with daily
• Build and scale our core financial infrastructure: payments, transfers, invoicing, bill pay, onboarding, and card management systems that move tens of billions of dollars a year
• Design data models, write migrations, and build the backend services that power complex multi-step financial operations
• Work directly with product, design, and compliance to ship features that are correct, compliant, and actually good to use — in financial software, the details are the product
• Shape engineering standards, contribute to architecture decisions, and talk to customers to figure out what to build next

We're Looking for Someone Who

• Has shipped and owned full product surfaces — not just isolated features, but entire systems from data model to deploy
• Is a strong full-stack engineer: comfortable designing API endpoints, writing a database migration, and building the frontend for a project end to end
• Has strong product instincts — thinks holistically about UX, API ergonomics, and system correctness, and pushes back when something doesn't feel right
• Thrives working independently in a small team that ships fast — you're the kind of person who builds product without requiring a full spec
• Cares about craft: writes clean, well-tested code, thinks about edge cases, and takes pride in building software that is delightful to use
• Bonus: Has an intuition for financial systems (payments, ledgers, compliance) or a genuine desire to go deep on them