Api integration development

Freelance Role: Backend API Integration Developer (AI Search System) Overview We are seeking an experienced backend developer to integrate an existing website with multiple AI APIs to enable AI-powered search and response functionality. This is a backend-only role. No frontend development is required. The system must connect to and coordinate responses from: * OpenAI API (ChatGPT) * Grok API * GitHub Copilot (or equivalent AI-assisted development tooling where applicable) ⸻ Scope of Work * Integrate AI APIs into existing website backend * Enable AI-powered search functionality via API requests * Route user queries between multiple AI systems based on logic rules * Build secure API authentication handling (API keys, OAuth2, JWT where required) * Process, transform, and return structured JSON responses to the website * Implement request validation and error handling * Handle rate limits, retries, and API failures * Ensure stable, scalable, production-ready performance * Secure all API communications and data handling ⸻ Required Skills (Strict) Applicants must have strong experience in: * REST API development and integration * Backend development (Node.js, Python, or equivalent) * Working with LLM or AI APIs in production * JSON schema design and structured data handling * Authentication systems (API keys, OAuth2, JWT) * Webhooks and asynchronous request handling * Debugging complex API systems independently * Building production-ready backend services ⸻ Additional Required Skills Candidates must also have experience with: * API orchestration or multi-service routing systems * Middleware or backend abstraction layers * Cloud deployment (AWS, DigitalOcean, or VPS environments) * Logging and monitoring systems for API usage * Rate limiting and API failure recovery strategies * Basic system architecture design * Security best practices for API-based systems ⸻ Nice to Have * Experience with AI workflow automation or agent systems * Experience integrating multiple LLM providers in one system * Familiarity with vector databases or embeddings * Experience with caching strategies (Redis or similar) * Experience building SaaS backend infrastructure * Knowledge of prompt engineering or AI response structuring ⸻ Deliverables * Fully working AI API integration with existing website * Multi-API routing system (ChatGPT + Grok + fallback logic) * Secure backend architecture for API handling * Structured response system (JSON-based outputs) * Documentation of all endpoints and system design * Basic monitoring or logging system for API usage ⸻ Engagement Type * Freelance / contract basis * Fixed project or milestone delivery * Optional ongoing maintenance available after completion ⸻ Application Requirements Please include: * Examples of API integrations you have built * Experience with AI/LLM systems * Backend technologies you are proficient in * Description of a complex API system you have built or maintained * Estimated timeline for delivery * Hourly rate or fixed project quote