Backend Engineer, API Platform

About The Role

The role builds APIs and internal services that clients and their millions of end users depend on daily, with strong Python or Node.js skills at the core.

You will work on a team that takes API design, data consistency, and performance seriously. If you want to work on interesting backend problems with real-world financial constraints, this is the role.

Key Responsibilities

• Design and implement REST APIs using FastAPI or Django (Python) or Express/Fastify (Node.js), with a focus on correctness, latency, and developer experience
• Own system design for new services: define data models, API contracts, error handling strategies, and operational requirements before writing a line of code
• Write and maintain PostgreSQL schemas and queries that perform well at scale; use Redis for caching and rate limiting where appropriate
• Build and maintain asynchronous task processing with Celery (Python) or Bull (Node.js) for payment processing, notifications, and compliance workflows
• Write comprehensive automated tests: unit, integration, and contract tests; treat test coverage as a first-class engineering concern
• Participate in on-call rotation (fair and infrequent); lead incident investigation and write clear post-mortems
• Contribute to internal engineering documentation, ADRs, and knowledge-sharing practices

What We Are Looking For

• 2–6 years of professional backend engineering experience with Python (FastAPI/Django/Flask) or Node.js (Express/Fastify/NestJS)
• Strong SQL skills in PostgreSQL or MySQL; understanding of transactions, indexing, and query optimization
• Experience with Redis for caching, queueing, or rate limiting
• Familiarity with REST API design best practices, versioning strategies, and HTTP performance fundamentals
• Experience with Docker and cloud deployment on AWS or GCP
• Clear written communication; can document system design decisions in a way that helps your team six months later
• Bonus: financial services domain knowledge, Kafka, gRPC, TypeScript, or experience building developer-facing APIs

Location

Chicago, IL (Hybrid)

• New York City
• San Francisco Bay Area
• Seattle
• Austin, TX
• Remote considered