Staff Backend Engineer (AWS / Serverless) - FT Freelance - Worldwide

Role Overview

We are seeking a dedicated Staff Backend Engineer specializing in AWS and serverless technologies to collaborate directly with our CTO. You will own the design and implementation of our core backend platform, focusing on building compliance-grade, event-driven systems. These systems will power receipt ingestion, audit logging, social activity feeds, and tax reporting workflows. Your role will be pivotal in guiding backend technical direction, making build-vs-buy decisions, and delivering scalable serverless systems on AWS, with occasional support to our React Native frontend.

Responsibilities

• Architect and build production-grade serverless backend systems on AWS using technologies like Lambda, API Gateway, RDS, S3, and CDK.
• Design and implement OCR and document processing pipelines for receipt scanning using AWS Textract and/or Google Vision AI.
• Develop inbound email parsing systems to extract structured donation data from forwarded confirmations.
• Implement immutable audit logging and long-term data retention strategies to ensure IRS compliance.
• Design event-driven workflows using AWS services such as SQS, Step Functions, and SNS.
• Architect social activity feeds with privacy controls and engagement tracking.
• Build programmatic PDF generation for tax reports and exports.
• Integrate third-party APIs for charity and EIN verification.
• Provide support to React Native frontend development as needed.
• Establish clean architecture, data models, and API contracts across the backend platform.

Required Skills

• Over 7 years of backend engineering experience with a strong track record of architecture ownership.
• Expertise in TypeScript and Node.js within production environments.
• Extensive experience designing AWS serverless architectures, including Lambda, API Gateway, SQS, Step Functions, S3, and RDS.
• Proficient in using PostgreSQL and ORMs like Prisma.
• Proven experience in building OCR and document processing pipelines.
• Skilled in implementing event-driven systems, audit logging, and compliance-grade data workflows.
• Experience in parsing and processing inbound emails for structured data extraction.
• Strong understanding of clean architecture, data modeling, and API design.
• Familiarity with regulated or compliance-sensitive environments.

Nice to Have

• Experience with event sourcing or change data capture (CDC).
• Experience integrating financial APIs such as Stripe or Plaid.
• Familiarity with IRS forms, tax workflows, or charitable donation systems.
• Experience in building social feeds or activity streams.
• Prior experience supporting React Native applications.
• Experience with CI/CD pipelines and infrastructure automation.