Travel Booking Platform Development & Multi-Supplier APIs Integration

We are an established European hospitality and travel network looking to scale our digital infrastructure and build a robust, high-load custom booking engine for accommodations and flights. The concept and high-level requirements are already documented, and the budget for a multi-month build is approved. We are looking for a long-term engineering partner rather than the cheapest bid, so please only apply if you have delivered comparable booking or reservation systems. Key Responsibilities & Project Scope: - API Logistics & Connectivity: Seamless integration of multiple third-party travel inventory suppliers and aggregators (e.g., Amadeus, Sabre,  Hotelbeds, Ratehawk, Cartrawler and others). - Core Engine: Developing a secure custom booking and reservation system (Flights//Accommodation/Transfers management layer) handling complex business logic, real-time availability sync, and payment routing. - Data Flow: Setting up automated pipelines to process and store historical transaction logs on a separate dedicated server for our future business intelligence needs. - UI/UX Implementation: Crafting a clean, highly usable interface (admin/B2B/B2C) based on modern web standards (React/Next.js/TypeScript). Preferred Technical Stack: - Backend: Java (Spring Boot / Hibernate) or Node.js. - Frontend: React / Next.js / TypeScript. - Architecture: Cloud-native, microservices-ready, secure data environments.