Senior SWE - Merchant Success & API (Remote)

We are looking for a Senior Software Engineer with 4-10 years of experience to build and own merchant-facing APIs on Truemed's payments and integrations team. You'll join a fast-moving, Series A startup backed by a16z and Bessemer that's building the infrastructure connecting $150B+ in pre-tax healthcare spending to products that actually improve health.

This is a backend-heavy, full-stack role where you'll be designing APIs consumed by major brand partners like Peloton, Nike, and Garmin — think disputes APIs, reconciliation APIs, and catalog APIs that power merchant onboarding and transaction processing. We want a high-slope senior engineer who thrives with autonomy, ships quickly, and is excited to own features end-to-end in a Django/Python monolith. What will you be doing?

Designing, building, and owning merchant-facing APIs (disputes, reconciliation, catalog) that enable partner brands to process HSA/FSA-eligible transactions Optimizing database queries and backend performance within a Python/Django monolith to support rapid merchant onboarding Building and iterating on the merchant dashboard — consuming your own public APIs as the first customer to ensure quality Collaborating with product and go-to-market teams to expand API interfaces as Truemed enters new merchant categories (e.g., nutritional breakdowns, new cart eligibility requirements) Leveraging AI tools (Claude, etc.) to accelerate development velocity and ship at startup pace