Senior Full-Stack Developer – Construction Management Platform (Existing Codebase)

Project Type: Contract | Remote | 4–6 Weeks Experience Level: Expert almost native English required Project Overview We're looking for an experienced full-stack developer to take over, improve, and complete an existing internal construction management platform. The application has already been built to a considerable extent using AI-assisted development tools (Chat Sites). Most of the interface and core modules exist, but we need a skilled engineer to review the codebase, resolve architectural and functional issues, connect workflows, and deliver a stable, production-ready system. This is not a project to build from scratch. We want someone who can understand existing code, preserve what's working, and complete the remaining functionality efficiently. Phase 1 Responsibilities Codebase Review: Audit the existing frontend, backend, database, architecture, and security. Identify and resolve structural issues. Daily Reports & Production Tracking: Complete a mobile-friendly field interface where foremen enter daily reports, labor hours, manpower, and production quantities against project-specific cost codes. Project Budgets & KPIs: Connect field production data with project budgets, performance calculations, and management dashboards. RFIs & Change Orders: Complete standardized forms, automated calculations, tracking logs, and PDF exports. Submittals: Finalize the submittal registry, tracking, and status management. User Roles & Permissions: Implement secure role-based access, project assignments, report submission, approval, and correction workflows. Existing Modules: Preserve and stabilize current bid management, scheduling, vendor directory, and project setup functionality. Deployment & Reliability: Establish source control, proper backups, testing, and a maintainable production environment. Required Experience Strong full-stack web application development and database architecture. Proven experience taking over and refactoring unfinished or AI-generated codebases. Building complex internal business platforms, ERP, CRM, or workflow management systems. REST APIs, authentication, role-based permissions, and relational databases. PDF generation, reporting dashboards, and data-driven workflows. Production deployment, debugging, testing, and performance optimization. Construction management software experience is strongly preferred, particularly project tracking, field reporting, cost codes, budgeting, and document workflows. Expectations We're seeking a developer who can work independently, communicate clearly, and take technical ownership. The expected Phase 1 timeline is approximately 4–6 weeks, subject to the initial code review. We expect clean, maintainable code, daily progress updates, documented changes, and fully tested deliverables. To Apply Please briefly answer: Have you taken over and completed an unfinished or AI-generated application? Describe one relevant project. Have you built construction management, ERP, CRM, or field reporting systems? What would be your approach to reviewing and stabilizing an existing codebase before continuing development? Can you commit to a 4–6 week development schedule? What is your availability? Please include links or examples of relevant projects. We're looking for an experienced engineer who can deliver a working system, not simply make visual changes to an existing website.