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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
Project ID: 40423049
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19 freelancers are bidding on average $110 AUD for this job

Hi, I have over 5+ years of experience in both frontend and backend development. I will do the specified tasks. Key Areas of Expertise: a) Full-Stack Development: Proficient in both frontend and backend technologies Frontend: Next, Js, ReactJS, Bootstrap, JavaScript, jQuery Backend: Laravel, CodeIgniter, Node.js b) API Integration: Experienced in integrating and working with APIs to enhance application functionality. c) Microservices: Skilled in developing and integrating microservices for scalable and efficient solutions. d) Database Management: Competent in managing databases with Postgresql, MySQL, MongoDB, and Oracle. d) Server Handling: Adept at handling server environments such as AWS, Google Cloud, VPS, Apache, and Nginx. Let’s discuss how I can help achieve your project goals and add value. Lets connect in chat so that We discuss further. With Regards, Sai
$95 AUD in 2 days
7.7
7.7

Hello, I specialize in building robust, production-ready backend integrations that orchestrate multiple AI services with clean, scalable architectures. For your AI Search System, I will design and implement a secure backend that connects OpenAI (ChatGPT), Grok, and GitHub Copilot or equivalent tooling, enabling intelligent, multi-source search and response flows. Key outcomes include a resilient API layer with JSON-structured outputs, strict request validation, and deterministic routing logic that selects the best AI provider based on the query and defined rules. The solution will feature secure API key management, OAuth2/JWT where required, rate-limit handling, retries, and comprehensive logging to monitor usage and performance. I will also deliver clear, developer-focused documentation and lightweight monitoring hooks to ensure long-term maintainability and observability. What is your preferred routing logic for selecting between ChatGPT, Grok, and Copilot outputs, and do you have existing authentication standards to align with (OAuth2/JWT)? Best regards,
$250 AUD in 4 days
7.0
7.0

Hello, I’ve read your AI search system plan and I’m confident I can wire up a robust, production-ready backend that orchestrates OpenAI, Grok, and Copilot-like tooling without touching the frontend. I bring deep REST API experience, strong Node.js/Python skills, and proven success building multi-service integrations in scalable environments. I will design secure API authentication, resilient routing logic, and JSON schemas for consistent, structured responses, while handling rate limits, retries, and observability. I’ve previously built backend systems that integrated several AI providers, implemented middleware layers for routing and transformation, and deployed on cloud infrastructure with monitoring and alerting. I’ll apply those patterns to your project, ensuring clean separation of concerns, secure keys management, and robust error handling so the site remains stable under load. I can take this from concept to a ready-to-run backend with clear endpoints and docs. I’m ready to discuss timelines and milestones today. Best regards, Billy Bryan
$250 AUD in 5 days
5.5
5.5

Hello, You need a backend developer to integrate multiple AI APIs like OpenAI, Grok, and GitHub Copilot into your existing website for AI-powered search and response. I can deliver a robust, secure, and scalable backend system focused solely on API integration and orchestration as you described. With extensive experience in Node.js backend development, REST API integration, and advanced authentication methods including OAuth2 and JWT, I recently built an AI-powered search backend that processed complex queries from multiple AI systems with over 99.9% uptime. My approach will be 1) map out your existing backend and API access details, 2) develop orchestrated multi-API routing with request validation and error handling, and 3) implement detailed logging and monitoring with secure authentication flows. I can provide the first milestone, a fully integrated API routing prototype with ChatGPT and Grok APIs, within 10 days. We can review it in a quick call or message for any adjustments. What existing backend technology stack and hosting environment does your website currently use? Best regards,
$180 AUD in 5 days
5.6
5.6

⚠️ If you're not happy, you don’t pay. ⚠️ Hi there, Thank you for checking my proposal and sharing the detailed project brief. I can build your backend API integration for an AI search system using Node.js and Python with a robust, scalable, and secure design. I will deliver: • AI API integration into the existing website backend • AI-powered search functionality with multi-API routing • Secure backend architecture for API handling • Structured response system with JSON outputs • Documentation of all endpoints and system design • Basic monitoring or logging system for API usage You will also receive: • Ongoing maintenance option post-completion I am confident I can execute your vision professionally and efficiently. Looking forward to discussing the timeline and next steps. Best regards, Chirag.
$200 AUD in 7 days
4.3
4.3

Hi there, I understand you’re building a robust backend API integration for an AI-powered search system that ties together OpenAI (ChatGPT), Grok, and GitHub Copilot-like tooling. I can deliver a scalable, secure, production-ready solution with clear routing logic and resilient error handling. Solution: - Backend integration (Node.js or Python) with RESTful APIs for OpenAI, Grok, and Copilot, plus a smart orchestrator to route queries. - Secure auth layer (API keys, OAuth2, JWT) and strict input validation for JSON payloads. - Multi-service routing rules with fallback to Grok or Copilot and structured JSON responses. - Rate limiting, retries, circuit breakers, and robust error handling. - Observability: logs, metrics, and lightweight monitoring; ready for deployment on AWS/DigitalOcean. - API gateway-friendly design with clear documentation and test endpoints. Deliverables: - Fully working AI API integration with multi-API routing and resilient handling - Secure backend architecture and authentication - JSON-based response schema and adapters for each AI API - Endpoint documentation and basic monitoring hooks - Architecture notes and deployment guidance Budget & timeline: - Fixed bid: 150 AUD - Timeline: 10-14 days, with milestones for integration, routing logic, and testing Ready to start and align on your exact routing rules and failure policies. Thanks, Best regards, Portfolio references: - https://www.freelancer.com/u/zarminagull189 - https://www.freelancer.com/u/z
$190 AUD in 3 days
3.2
3.2

Greetings I can surely help you for Api integration development I am in the IT industry since more than a decade and serve so many clients in building and rebuilding websites, software, and applications I have strong hands-on different cms like webflow, Wordpress, shopify, squarespace, wix and on different programming languages like PHP, Laravel, React, Node.js, HTML, CSS, And I did the migration from HTML to click funnels. I have made so many websites (E-commerce, WordPress, Classified admin, WooCommerce, etc.), bots, softwares, and Mobile applications (Android, IOS, and Huawei Play store) in my entire career. I have strong hands on both the front end and back end. Currently, I am part of the team who are dealing with miscellaneous tasks in dubizzle and Mzad Qatar including design and layouts and they both have more than 1 million users. I believe that you are looking for a web designer and for sure you will get your end desire result with plagiarism-free work and with better quality as I am assuring you this. Package deals can also be done for long-term collaboration as per the client's requirement. Kindly do come on chat so that we can discuss project details further more.
$30 AUD in 2 days
3.2
3.2

Hi, I see you're looking for someone to integrate those AI APIs and create a solid backend for your search system. That kinda setup can be tricky, especially with the need for secure, reliable routing between them. I’ve worked on projects just like this before, handling API integrations with OpenAI and other LLMs. I’m comfortable with Node.js and have built production-ready systems that deal with complex API orchestration and error handling. Plus, I can get the initial integration up and running in about 5 days, maybe even faster. One thing to think about: have you considered how your API will handle traffic spikes? Might be worth discussing a caching strategy or rate-limiting tactics to keep everything smooth. Best regards, Walled Saleem
$100 AUD in 7 days
2.5
2.5

Hey, I’m Roman. Your backend-only AI search integration project fits exactly what I do. I’ll wire your site to OpenAI, Grok, and Copilot-like tooling and build a routing layer that sends queries to the right AI, with fallbacks and clean JSON outputs. I’ll implement secure API authentication (API keys, OAuth2, JWT), input validation, error handling, rate limiting, retries, and solid logging for production. I’ve built production REST services in Node.js and Python, connected to AI APIs, set up webhooks and asynchronous processing, and designed JSON schemas for multi-service data flows. Examples from my recent work include a multi-LLM backend that routes prompts between OpenAI and a vector-service with Redis caching, plus a middleware layer that manages auth and retries across services. Deliverables you want are in reach: functioning AI API integration, multi-API routing, secure architecture, JSON-based responses, endpoint docs, and basic monitoring. Timeline: MVP in 2–3 weeks; full production in 4–6 weeks. Rate: $70/hr or a fixed MVP quote around $8k–$12k depending on scope. If you want, let’s jump on a quick call to lock scope and milestones.
$140 AUD in 7 days
2.4
2.4

Hello, I am a Senior Developer with 10+ years of experience in building scalable web and mobile applications. Over the past 4 years, we have successfully delivered 60+ freelance projects for startups and growing businesses, focusing on quality, performance, and long-term scalability. Our expertise includes: • End-to-end product development (from requirement gathering to deployment) • System architecture & scalable solution design • Agile methodology & SDLC best practices • Strong communication and seamless collaboration Looking forward to your response. Best regards, Vimal
$30 AUD in 7 days
0.0
0.0

Hi there. I see you're looking for a backend developer to integrate various AI APIs into your existing website. This involves connecting to the OpenAI API, Grok API, and potentially GitHub Copilot, while ensuring smooth communication between these services and your platform. A common challenge here is managing the routing of user queries effectively to achieve the best responses. I have over 7 years of experience in building scalable backend systems, including multiple API integrations with AI technologies. I've developed secure APIs and implemented complex routing logic in production-grade applications. I can help you create a robust backend that handles API authentication, manages rate limits, and processes responses in a structured way. My focus will be on delivering a solution that is both reliable and secure. What is your timeline for this project? Best regards, Dobrivoje Jesic
$140 AUD in 7 days
0.0
0.0

Hello, With over five years of extensive experience in API and backend development, I believe I am the ideal candidate for your project. I have successfully integrated a wide range of APIs into various websites which have improved their functionality tremendously. My proficiency in Node.js and Python will ensure seamless integration of the requested AI systems, such as ChatGPT, Grok API and Github Copilot into your website's backend. Regarding security, I am well-versed with implementing robust authentication handling using API keys, OAuth2, and JWT to safeguard your API communications and data handling. Rate limits, retries and API failures causing issues? fret not! I have been skillfully managing these challenges in many past projects. As an advocate of maintainable, scalable, and practical system designs that ensure long-lasting reliability, I employ structured JSON responses that not only deliver what is required from the backend but also guarantee an improved frontend user experience. My deep knowledge on LLM and AI APIs will help route user queries efficiently between multiple AI systems based on logic rules while maintaining optimum response times. Let's move forward with confidence toward a project that will deliver real value! Thanks!
$30 AUD in 5 days
0.0
0.0

Hello, With experience in AI/ML development, Full Stack, and a strong specialty in Backend engineering using Node.js and RESTful APIs, I am confident I can provide you with the high-quality API integrations your project demands. I’m well-versed in transforming JSON structured data and maintaining JSON schema design which will be beneficial in enabling AI-powered search functionality via API requests on your platform. Working within webservices is second nature to me, as seen by my familiarity with LLM or AI APIs in production, use of Authentication systems (API keys, OAuth2, JWT), and my proficiency with Webhooks. Additionally, my knowledge in rate limiting and error handling strategies ensures that your system doesn't encounter any hiccups due to the demands of the multiple AI systems. Furthermore, I've got great skills in moving huge amounts of data from one point to another securely; thus processing, transforming, and returning structured JSON responses wouldn’t be an issue. As a bonus skillset I offer my experience building SaaS backend infrastructure - another key requirement for the project. Finally yet importantly providing you not just with a solution but also ensuring appropriate documentation to give your team an upper hand in future system handling is a given with me. My availability and hourly rates are flexible th roughout the application requirements so we can ensure quality end-to-end integration for your existing w Thanks!
$30 AUD in 4 days
0.0
0.0

Hello, As an experienced freelance AI/ML Engineer and Developer with a proven track record in LLM-powered agents, Retrieval-Augmented Generation (RAG) and real-time AI automation, I have the exact skillset you need for this project. With deep knowledge in backend development, specifically using technologies such as Node.js and Python, I am highly proficient in REST API development and integration, working with LLM or AI APIs in production, JSON schema design, authentication systems like API keys, OAuth2, JWT, debugging complex API systems independently and much more. My previous works testify to my expertise. For instance, I developed a compliance copilot using RAG + LangGraph, which can be linked to your project. Additionally, my experience with process automation --such as building an RL-based email follow-up agent that self-optimized via reward loops or building multilingual AI chatbots --has enabled me to develop a strong understanding of workflow orchestration for projects just like this one. In conclusion, I understand the task at hand: integrating multiple AI APIs into the existing backend of your website for a seamless search function and ensuring secure API communications. My proficiency in cloud deployment, rate limiting strategies and architectural design will contribute significantly to a stable and scalable final product. Being familiar with vector databases or embeddings is also an added advantage which ensures struct Thanks!
$30 AUD in 4 days
0.0
0.0

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