Agency: lead architect + 2 devs, React + Supabase business platform, fixed price per module

In short: 6-month build of an internal business platform for a German field service company (~30 employees). We look for one agency with a lead architect and at least two React/Supabase developers working in parallel. Rough estimate: about 1,200–2,000 hours for modules 1–5 (our rough estimate only, your estimate per module decides). Fixed price per module. Module 1 can start this week. About us and what exists today We are MS Dach GmbH, a German roofing and gutter-cleaning company. We are replacing our legacy office software step by step. Already in production: - Internal web app (React + TypeScript + Supabase, ~100 tables, Edge Functions, RLS): employees, time tracking, technician app, piece-rate payroll, payroll export. - Sales CRM (React + Supabase), maintained by another developer. - n8n (self-hosted) for e-mail AI, messaging and integrations, run by another developer. - A read-only mirror of our legacy ERP in Supabase (customers, objects, orders, invoices). - Invoicing moves to ERPNext, set up by a separate freelancer. Supabase stays the leading system up to "ready to invoice". Team setup we want - Lead architect (part-time, please state the hours per week you plan for this role): owns the data model and the interfaces between all systems (office app, Sales CRM, n8n automation, ERPNext). Reviews every pull request, coordinates in writing with the other developers on our side, keeps the shared specs up to date and sends us a short weekly written status. Does not need to code full time. - At least two developers in parallel on the office app, so that modules can run side by side and we keep the timeline. - Shared Claude projects: we run one shared Claude project per area (ERPNext, Sales CRM, office app/HR tool, automation). All developers on all teams work in them. Every team writes a short status at the end of each working day (decided, done, open, what affects others), so everybody always sees the current state of the other areas and builds against the same specs and interfaces. Your lead and developers take part in this; it is part of the job. What we need built (each module priced separately) 1. Payroll export fixes in the existing app (first module, fully specified). 2. Shared data model: customer → objects → invoice recipients → projects → orders/positions. 3. Quotes and orders. 4. Dispatch / planning board / tours, plus technician "job done" with extra work and photos. 5. Office workplaces: tour billing, invoice review, dunning proposals, payment clarification list. 6. Later: merge the Sales CRM into the same app. How we work - Fixed price per module, paid by Upwork milestone after acceptance. Each module gets a written spec with measurable acceptance criteria before you quote. - The people named in your proposal do the work. Changes only with our written approval. - All code, migrations and Edge Functions in OUR GitHub and OUR Supabase organisation. Pull requests only, migrations in Git, no direct changes in production. - AI-assisted development with Claude Code (or similar) plus tests for business logic. - English, written communication only (no calls, no videos). Please include in your proposal 1. Two live business apps your team built with React + Supabase (link or read-only access), at least one with roles/permissions, and who built them. 2. Read-only repo access or an anonymised code sample (one migration, RLS policies, one Edge Function, tests). An anonymised sample is fine. 3. Your Claude Code workflow in 5–10 lines: how you plan, review and test AI-written code. 4. Your team for this project: lead architect + developers with names, Upwork profiles, hourly rate, hours per week, time zone. 5. A rough estimate (hours + price range) for modules 1–5. Final fixed prices follow after the detailed specs. 6. Two previous clients with similar business apps (ERP, CRM, dispatch, billing) we may contact via Upwork message. 7. Number of contracts your team runs at the moment. Proposals without points 1, 2 and 4 will not be considered. Module 1 – first fixed-price contract (start this week) Fix the payroll export of the existing app (about 11 defined errors: compensation requests, net deductions, negative bonus, mini-job amount, export period, booking month, subcontractors, etc.). Detailed spec with expected values is ready. Acceptance: the export for a reference month matches our corrected reference file exactly, without manual correction.