Senior Full Stack Engineer (Backend Focus)

Senior Full-Stack Engineer

Employment Type:Full time, independent contractor (​​Short Term Contract)Work Model:RemoteWork Hours:US work hours

Role Overview

We are seeking aSenior Full-Stack Engineerto build a production-ready application that usesLLM vision models to extract structured data from imagesand transform it into validated outputs forhealthcare billing workflows.

This role isbackend-dominant but fully full-stack. You will implement amulti-stage data extraction and validation pipeline in Python, integrate it with an existingReact frontend, and deploy the system onGoogle Cloud Platform.

The project has already been extensively scoped. Over130+ pages of architectural documentation, technical decision documents, and validation rulesare available. Your primary focus will beimplementation, integration, testing, and production hardening, rather than early product discovery.

You will work directly with thefounderto transform the detailed specification into a reliable production application.

About the Product

The platform extractsbilling data from hospital census sheets used by physicians.

Doctors photograph their patient lists, and the system:
* Validates image quality on-device
Validates image quality on-device
* Extracts structured data usingLLM vision models
Extracts structured data usingLLM vision models
* Runs amulti-stage backend validation pipeline
Runs amulti-stage backend validation pipeline
* Allows physicians to review extracted data
Allows physicians to review extracted data
* Exports validated records to billing software
Exports validated records to billing software

The goal is toeliminate hours of manual transcription work physicians perform each week.

Core Architecture

Mobile App:React + CapacitorBackend:Python + FastAPIInfrastructure:Google Cloud RunDatabase:PostgreSQL or FirestoreLLM Vision:Claude (primary) with backup providerCI/CD:GitHub ActionsCompliance:PHIPA healthcare privacy requirements with Canadian data residency

What You’ll Build

This project centers around adata extraction and validation pipeline, not a traditional CRUD application.

Data Extraction Pipeline
* IntegrateLLM vision modelsto extract structured data from uploaded images
IntegrateLLM vision modelsto extract structured data from uploaded images
* Implementfailover logicbetween primary and backup model providers
Implementfailover logicbetween primary and backup model providers
* Normalize and parse model outputs into structured backend objects
Normalize and parse model outputs into structured backend objects

Validation & Business Logic

Build amulti-step validation systemincluding:
* Billing code normalization and database validation
Billing code normalization and database validation
* Diagnostic code resolution
Diagnostic code resolution
* Date format disambiguation
Date format disambiguation
* Physician lookup and reference dataset matching
Physician lookup and reference dataset matching
* Data confidence scoring
Data confidence scoring

Extracted data must be categorized into:
* High-confidence
High-confidence
* Review-required
Review-required
* Invalid
Invalid

before export.

Backend Infrastructure
* Build backend APIs usingPython and FastAPI
Build backend APIs usingPython and FastAPI
* Design securedata pipelines and database schemas
Design securedata pipelines and database schemas
* Implement validation and processing workflows
Implement validation and processing workflows
* ConfigureCI/CD pipelines and cloud infrastructure
ConfigureCI/CD pipelines and cloud infrastructure

Frontend Integration
* Review and integrate an existingReact + Capacitor frontend
Review and integrate an existingReact + Capacitor frontend
* Connect backend APIs to the mobile UI
Connect backend APIs to the mobile UI
* Implement state management, validation states, and error handling
Implement state management, validation states, and error handling
* Ensuremobile-grade reliability and resilience
Ensuremobile-grade reliability and resilience

Export Pipeline
* Generatespreadsheet outputs compatible with billing software
Generatespreadsheet outputs compatible with billing software
* Implementmulti-layer validation gates before export
Implementmulti-layer validation gates before export
* Prevent invalid data submissions through deterministic checks
Prevent invalid data submissions through deterministic checks

Key Responsibilities
* Implement aproduction-ready full-stack system from detailed specifications
Implement aproduction-ready full-stack system from detailed specifications
* Build backend services usingPython and FastAPI
Build backend services usingPython and FastAPI
* Integrate and validate aReact + Capacitor frontend
Integrate and validate aReact + Capacitor frontend
* Deploy and manage infrastructure onGoogle Cloud Platform
Deploy and manage infrastructure onGoogle Cloud Platform
* ImplementCI/CD pipelines and secure DevOps practices
ImplementCI/CD pipelines and secure DevOps practices
* Build reliabledata