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Fiverr Pro
English
$
USD
I will build or connect apis to your app in angular, react, next, aspnet or node
Felix O.
About this gig
Are you struggling to integrate an external API into your website or web application? Whether it's a payment gateway, third-party service, or a custom API, I've got you covered!
Hi, I'm Felix, a certified full-stack web developer with hands-on experience in API development and integration using .NET Core, Node, JavaScript and DBs. I specialize in helping businesses connect and communicate with third-party services through reliable and secure APIs.
What I Offer:
Integrate third-party APIs (RESTful, SOAP, JSON-based)
Develop and consume custom Web APIs
Handle API authentication (Bearer Token, OAuth, API Keys)
Connect frontend (AngularJS, React, or JavaScript) to APIs
Debug and fix API integration issues
Improve performance of slow or failing API calls
Secure sensitive data using best practices
Tech Stack I Work With:
- Backend: ASP.NET Core, Node.js
- Frontend: AngularJS, React, JavaScript
- Database: SQL and No SQL
- API Tools: Postman, Swagger, Insomnia
- Version Control: GitHub
Examples of APIs I Can Help You With:
- Payment Gateways (Stripe, PayPal, Flutterwave, Mpesa)
- Social Media APIs (Facebook, Twitter, LinkedIn)
- Shipping APIs (DHL, FedEx, Sendy)
- Authentication APIs (Firebase, Auth0)
Get to know Felix O.
Felix O.
Full Stack Web Developer: AI, React, Next, Angular, Node, ASP NET, QA Testing
- FromKenya
- Member sinceMar 2024
- Avg. response time1 hour
Languages
English, Swahili
Need a developer who can turn your idea into a fast, modern, scalable app? I help businesses build reliable systems that look great, perform smoothly, and grow effortlessly.
I specialize in building robust web apps using React, Next, Angular on the frontend and Node/Express and ASP.NET on the backend with database design (Prisma/EF + PostgreSQL), and integrations like M-Pesa API, Stripe and third-party REST APIs.
I build systems that are tested, reliable, and maintainable. I work with Jest, Cypress, xUnit, K6, and Jasmine across both JS and .NET stacks.
Let’s build something exceptional. 🚀✨
My Portfolio
Other Software Development Services I Offer
FAQ
What do you need from me to get started?
I’ll need a clear description of your requirements, access to your API documentation (if you're using a third-party API), credentials or tokens (if authentication is required), and your codebase (if integrating to an existing project). If I’m building the API, I’ll need your data structure and logic
Can you create a custom API from scratch for my application?
Absolutely! I can build secure and scalable RESTful APIs using ASP.NET Core, including features like CRUD operations, authentication (JWT, OAuth), and integration with SQL and NoSQL databases.
Will you test the API after integration or creation?
Yes! I test all APIs using tools like Postman or Swagger, ensuring they perform well, return accurate data, and handle errors gracefully. I can also share the Postman collection for your convenience.
Can you help fix or troubleshoot my existing API?
Definitely. If your current API is broken, slow, or not functioning properly, I can help diagnose and fix the issue as long as I have the right access and documentation.
Will I get documentation for the API?
Yes! For custom APIs, I provide clear API documentation (usually via Swagger/OpenAPI). If I’m integrating a third-party API, I include integration notes and response details in the handover.
I have a tight deadline. Can you deliver faster?
I offer express delivery depending on the complexity of the task. Please message me before ordering so I can confirm availability and adjust timelines accordingly.
I'm not tech-savvy. Can you explain everything in simple terms?
Absolutely. I believe in transparent and friendly communication. I’ll guide you step-by-step and ensure you understand how the API works with your application even if you're not technical.
