Senior Backend Engineer - Payments & Fintech (SF On-site)

The French Sourcer; San Francisco (CA); On-site; USD 170,000 - 230,000; Full time

Job summary

The French Sourcer is seeking a Senior Backend Engineer in San Francisco to own core backend systems powering payments and credit workflows. You will design APIs and data contracts used by data science and risk teams, and you’ll build internal tools to trace decisions without always pinging an engineer.

You’ll work with TypeScript in production, on a serverless AWS stack, and tackle reliability and latency challenges while shipping end-to-end solutions for live enterprise transactions.

Qualifications

• 5–12 years of backend engineering experience with production ownership.
• Strong hands-on experience with TypeScript in production.
• Experience in payments, fintech, or credit/risk systems.
• Comfort with AWS, serverless architecture, and designing for reliability at scale.

Responsibilities

• Own production backend systems powering core payments and credit workflows using TypeScript and Node.js.
• Design APIs, services, and data contracts used daily by risk, data science, and product teams.
• Build internal tools to review decisions and trace data lineage without engineering help.
• Turn ambiguous problems into shipped, production-grade components.

Skills

TypeScript

Node.js

SQL

AWS

Tools

AWS Lambda

PostgreSQL

Snowflake

Job description

The French Sourcer is seeking a Senior Backend Engineer in San Francisco to own core backend systems powering payments and credit workflows. You will design APIs and data contracts used by data science and risk teams, and you’ll build internal tools to trace decisions without always pinging an engineer.

You’ll work with TypeScript in production, on a serverless AWS stack, and tackle reliability and latency challenges while shipping end-to-end solutions for live enterprise transactions.