Build a Secure SaaS Web App: Real-time Chat + Auto-Vault Document Management (Next.js/Supabase)

I am looking for an individual developer to build a secure, mobile-first web application. The core functionality is a WhatsApp-style 1-on-1 chat interface where every shared file is automatically captured and permanently stored in a secure, categorized document vault. Tech Stack (Strict - Do not propose alternatives): Frontend/Backend: [login to view URL] 14+ (App Router), TypeScript, Tailwind CSS. Database/Auth/Storage/Realtime: Supabase (Postgres, RLS, Storage Buckets, Realtime). Phone Authentication: Phone Auth (OTP) for Indian numbers (+91), bridged to Supabase sessions. Hosting: Vercel. Core Features to Build: 1. Authentication & Role-Based Access: Firebase Phone OTP login. A [login to view URL] API route must exchange the Firebase ID token for a Supabase session cookie. Four roles: Admin, Professional, Assistant (Scoped Professional), Client. Row-Level Security (RLS) on all tables. Assistants can only view data for clients explicitly assigned to them. Professionals see all their clients. 2. WhatsApp-like Chat Interface: Left sidebar (list of active 1-on-1 conversations) + Right panel (message thread). Real-time messaging for text using Supabase Realtime. File attachments: Support images, PDFs, Excel/CSV, and ZIP files (stored in Supabase Storage). Mobile-first layout (sidebar and chat window toggle on mobile screens). 3. The "Auto-Vault" Logic (Critical Feature): When a user sends a file in the chat, the system must instantly create a row in a vault_documents table (status: pending). Immediately after the file sends, a modal popup must force the user to categorize the file (Dropdown for Category, Dropdown for Financial Year). If the user skips the modal, the file remains in the vault as pending. Files must never be lost, even if deleted from chat. 4. Vault Management Dashboard: A separate screen to view all auto-saved documents. Filters: By Category, Financial Year, File Type. Full-text search across file names. 5. Client Management & Fees: Professionals can add clients via phone number lookup/creation. Fees Tracker: A simple table showing Client Name × Financial Year with a toggle button: "Paid" (Green) / "Not Paid" (Red). Strictly no input fields for fee amounts. 6. Family Groups: Professionals can group multiple clients together. When uploading/tagging a document, the UI must allow selecting which specific family member the document belongs to. 7. Public Digital Business Card: A public, unauthenticated route (/pro/[slug]) displaying the Professional's logo, name, phone, and custom brand color. A "Save Contact" button that generates and downloads a .vcf file. Expected Database Schema (To base your quote on): users (id, phone, role, firm_name, logo_url, theme_color, slug) conversations (id, professional_id, client_id) messages (id, conversation_id, sender_id, content, attachment_url, type) vault_documents (id, client_id, professional_id, file_url, category, fy_year, tagging_status, linked_message_id) families & family_members (grouping clients) fee_statuses (client_id, professional_id, year, is_paid) Design Expectations: Highly polished, mobile-first UI. The chat interface must look and feel exactly like WhatsApp Web. I will provide high-level wireframes, but you are expected to handle UI/UX implementation, spacing, and responsive design. What I need from you: Please provide a fixed-price bid based strictly on the stack and schema provided above. Include links to live web apps you have built that feature real-time chat or complex file management. Estimated timeline for MVP delivery. Do not use generic cover letters. Mention "Auto-Vault" in your proposal so I know you read the requirements. Required Skills: [login to view URL], TypeScript, Tailwind CSS, Supabase (Postgres, RLS, Storage, Realtime), Firebase Auth, Vercel.

Project ID: 40532586