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# Backend Engineer, API

- **Company:** Pylon Manufacturing Corp.
- **Location:** San Francisco, CA, United States
- **Salary:** $140,000.0 - $220,000.0
- **Contract:** Permanent contract
- **Skills:** Application Programming Interfaces (APIs), Artificial Intelligence, Encodings, Software Design Documents, PostgreSQL, SQL Databases, TypeScript, Management of Software Versions, Backend, Event Driven Architecture, Graphql, NestJS
- **Published:** October 27, 2026
- **Apply:** https://www.careerbuilder.com/job-details/backend-engineer-api-san-francisco-ca--5c64c270-329a-40bc-91d8-aa3b2d4667a5

## About the Role

Application Programming Interface (API), Financial Systems, Mortgage, Underwriting, Application Programming Interface (API), GraphQL, Design Document, Product Design, Onboarding, Artificial Intelligence (AI), * Is deeply curious

 * Wants to won features from design to development to deployment to maintence
 * Is willing to put the work in to solve the hardest of problems

## Description

We're looking for Back End Engineers to join our API team. We treat our GraphQL API as a product - because it is one. Multiple customers build directly on top of it, and the quality of their experience is determined by how well we design, document, and maintain it.

Mortgage is a surprisingly rich domain to model. It's path-dependent: the choices you make early in a loan constrain what's possible later. It's nonlinear: different borrower situations branch into wildly different flows. Most APIs in this space paper over that complexity. We're building one that embraces it - encoding the real shape of mortgage into a surface that's impossible to misuse and delightful to build against.

Here Is What You'll Do

 * Define what a mortgage is in code. Seriously. You'll work on semantic models that don't just represent mortgages as they exist today - they expand what a mortgage can be. This is product design at the API layer.
 * Build toward an event-driven API. We're moving to a world where our API doesn't just respond to requests - it tells you what happened, why, and what you can do next. You'll help design and ship that future.
 * Make the complex feel simple. Our API should make the mortgage process impossible to get wrong. That means thoughtful abstractions, clear documentation, and an obsessive focus on developer experience.
 * Design for nonlinearity. Mortgage flows aren't linear wizards. Our future API encodes choice, branching, and path-dependence natively. You'll work on guided experiences that model real-world complexity without exposing it as chaos.
 * Treat this as a product surface. You'll think about breaking changes, versioning, onboarding, and the full lifecycle of an API that real companies depend on.

Tech Stack

 * TypeScript
 * GraphQL (this is the product)
 * NestJS
 * SQL (PostgreSQL)
 * Temporal.io (workflow orchestration)
 * Event-driven architecture
 * AI-driven development tooling and agentic infrastructure