Need Senior SaaS MVP developer for long term

We are looking for an experienced Senior Full-Stack Developer with strong Next.js and Node experience to help maintain and expand an established SaaS project management platform. Most work will be focused on backend services, APIs, database design, Supabase infrastructure, internal tools, performance, and modernization of existing systems. Responsibilities include maintaining and extending backend services and APIs, working with core product entities such as projects, tasks, teams, permissions, notifications, and billing/subscriptions, building and improving internal admin tools and reporting utilities, debugging production issues, working with Supabase (Postgres) and related data layers, maintaining and improving infrastructure and deployment pipelines, improving logging, monitoring, deployment, and CI/CD, modernizing legacy parts of the codebase without disrupting the live product, building scripts, reporting tools, and operational utilities, and contributing to frontend work in Next.js as needed. Relevant technologies include Next.js/React, Node.js, TypeScript, Supabase/PostgreSQL, REST APIs, WebSockets/real-time subscriptions, Git, and Linux. You do not need to be an expert in every technology listed. We are looking for someone with strong backend and full-stack experience who is comfortable taking ownership of an existing production system and working independently. Experience with SaaS products, multi-tenant architectures, subscription billing (e.g., Stripe), or scaling Supabase/Postgres in production is a major plus. This is a full-time, long-term engagement (~40 hrs/week) for the right developer. When applying, please briefly describe your backend experience, Supabase experience, strongest languages, and any experience working on live SaaS or production applications.