Web App Developer for Production Deployment

We need a developer to connect an existing browser-based construction progress management app to a production database, deploy it online, and maintain it. The work includes reviewing and improving the current code without rebuilding the UI, configuring Supabase/PostgreSQL, migrating demo data, and implementing authentication, user roles, and secure access to project data. You will deploy the app with a custom domain and HTTPS, set up backups and monitoring, fix bugs, and prepare the system for future multi-company SaaS use. Please share relevant experience, live examples, a fixed-price estimate for launch, monthly maintenance charges, and your expected timeline. The project will start with a paid technical audit and clear implementation scope.