Flutter + FastAPI Full-Stack Developer for Pet Services App

We are looking for an experienced Full-Stack Developer / Development Team to build Pet Services Mobile Application.

Mobile Application

Flutter / Dart
Android & iOS
Modern, responsive UI
Dynamic UI / Schema-Driven architecture
Both Flutter Mobile and Next.js Customer Web must be capable of rendering supported dynamic schemas using reusable Dynamic UI components/renderers.

Fronted → Next.js + React + TypeScript → Customer Web + Super Admin Panel
Category & Subcategory Management
Dynamic Field & Form Management
User & Service Provider Management
Subscription, Leads, Advertisement & Reports

⚙️ Backend

Python + FastAPI
REST APIs
Business Logic
Authentication & Authorization
Payment
Subscription
Wallet
Lead Management
Chat
Booking
Notifications
Verification

Database & Infrastructure

PostgreSQL + JSONB
Redis
Docker
Linux VPS
Nginx
Secure & scalable architecture

Main Platform Features
Template + AI tools (Cursor + Claude) → can reduce the developer's work by about 70–75%.
The application will support:

Pet Buying & Selling
Pet Adoption
Pet Shop & Product Listing
Pet Food & Accessories
Veterinary Doctors
Pet Hostel / Boarding
Pet Care Services
Booking
Chat
Lead Management
Subscription Packages
Wallet & Payments
Service Provider Verification
Advertisement / Campaign System
Phone OTP: WhatsApp Cloud API as primary OTP channel, with SMS fallback.
Important Requirement

Flutter will compare the locally cached Schema Version with the server version. If the version has changed, it will download and validate the new JSON Schema, update the local cache, and render the UI using the existing Dynamic UI Widgets. Therefore, normal Category/Subcategory/Field changes do not require a database migration or a new APK release. New widget type or genuinely new business functionality may require code changes and a new application release. Dynamic configuration does not mean unlimited new functionality.

Super Admin controls the configuration.
Flutter and Web handle UI rendering and client-side validation. Backend is the ultimate authority for schema validation, authorization, business rules, transactions, security, and data integrity.
Backend controls the business logic and security.
Database stores the configuration and dynamic data.

Admin creates category → adds dynamic fields → backend generates/version-controls schema → Flutter and Web retrieve schema → UI renders without client code changes → data submission succeeds

A suitable CodeCanyon Flutter UI template may be provided as the UI foundation. Developer should reuse existing components/screens wherever technically appropriate instead of rebuilding equivalent UI from scratch.

The application should use a Schema-Driven / Dynamic UI architecture, allowing Super Admin to create or modify categories, subcategories and fields from the Admin Panel without requiring a new mobile screen for every category.

We are looking for a developer/team with experience in Flutter + FastAPI + PostgreSQL + Next.js and scalable marketplace/service-platform development.

Please share your previous similar projects, portfolio/GitHub, estimated timeline and budget.

POC/technical discussion may be required before final selection.

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We want to implement a Schema-Driven / Metadata-Driven Dynamic UI Architecture, but we do not have a pre-existing JSON schema or a finalized UI theme.

If schema update fails due to network/server issues, the application must continue using the last known good local schema cache and must not crash or lose user-entered data.

The overall architecture and dynamic principles are already defined. You will need to design and implement the exact JSON Schema structure and Dynamic UI Engine based on these agreed principles.

The Super Admin must be able to dynamically configure categories, subcategories, fields, field types, labels, options, validation rules, ordering, visibility, searchable/filterable properties, etc., and the Flutter application must render them through a reusable Generic Dynamic UI Engine.

For the UI theme, we do not have a pre-existing theme or Figma design. You may propose and implement a clean, modern, professional, and user-friendly UI suitable for a PET marketplace/application.

However, the core architecture and the Dynamic UI principles should remain as agreed and should not be changed without prior approval.

Before starting the main implementation, please share your proposed JSON Schema structure, Dynamic UI Engine approach, widget registry structure, and UI/theme direction for review.

Let me know if this is clear.