Senior Full-Stack Engineer (Contract, Remote)

Senior Full-Stack Engineer — Contract, RemoteJS Technology Solutions is sourcing a Senior Full-Stack Engineer for an immediate-start contract engagement building an AI-powered invoice automation system for a healthcare client. This is a fully remote role with an initial term of approximately 3 months, with strong potential for extension.What you'll do:Build and own a Node.js backend service that reads invoices from SharePoint via Microsoft Graph API, processes them through Azure Document Intelligence, and outputs structured data for import into a third-party accounting systemBuild a Next.js frontend: AP Manager review interface with split-screen invoice view, approval routing, and run history dashboardDesign and implement a PostgreSQL schema on Azure for invoice records, processing history, and duplicate detectionConfigure Azure Service Bus for pipeline orchestration and failure handlingImplement a three-tier approval routing engine (auto-approve, admin approval, admin + regional approval)Implement duplicate invoice detection (vendor + amount + service period matching)Own the architecture end-to-end — you will make the key design decisionsWhat we're looking for:5+ years full-stack development experienceStrong Node.js backend fundamentals — async patterns, error handling, pipeline architectureNext.js frontend experience — server components, API routes, state managementHands-on Azure experience: Document Intelligence (Form Recognizer), Service Bus, PostgreSQLMicrosoft Graph API / SharePoint integration experienceSelf-managing — you drive your work to completion without daily supervisionAsync-first communication — you write clearly, flag blockers early, and don't need hand-holdingComfortable with a fast-moving, low-ceremony client environmentPluses (not required):Experience with healthcare AP or ERP integrationsDocker / Azure Container Apps deployment experienceOCR pipeline tuning experienceTypeScriptEngagement structure: Contract, fully remote, ~3 months initial term. 40 hrs/week. Timezone overlap with US Central (Chicago) required — at minimum 4 hours of daily overlap.Apply via LinkedIn or message directly with a brief note on your most relevant experience.