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You will get API Integration Expert | API Gateway Solution Developer | Data Sync via API

Muddasar H.Status: Offline
Muddasar H. Muddasar H.
5.0
Preview image

Let a pro handle the details

Buy Web Application Programming services from Muddasar, priced and ready to go.
Muddasar H.Status: Offline
Muddasar H. Muddasar H.
5.0
Preview image

Let a pro handle the details

Buy Web Application Programming services from Muddasar, priced and ready to go.

Project details

I am an API Integration Specialist, and I’m here to help you connect your applications with any third-party service through reliable, secure, and well-documented API integrations.

With hands-on experience building and integrating APIs in Node.js, Express, and React Native, I’ve helped startups and enterprises automate workflows, sync data across platforms, and unlock the full power of external services through custom API solutions.

🔧 Services I Offer:

RESTful & GraphQL API Integration.
Third-party APIs (Stripe, Twilio, Firebase, Google Maps, PayPal, SendGrid, etc.).
Custom backend-to-backend API communication.
Webhooks setup and processing.
API authentication (OAuth2, API keys, JWT).
API Gateway setup and configuration (including AWS API Gateway).
Scheduled data sync (cron jobs, real-time sync).
Error handling, retries, and rate limiting.
Postman collections, API documentation & testing.

⚙️ Typical Use Cases:

Integrating payment gateways (e.g., Stripe, Razorpay).
Real-time chat and notification systems using APIs.
Connecting mobile apps to cloud services.
Data migration or syncing across SaaS platforms.
Building API layers for frontend/mobile apps.
Programming Languages
JavaScript, Python, Ruby/Ruby on Rails
Coding Expertise
Performance Optimization, Security

What's included $100

These options are included with the project scope.

$100
  • Delivery Time 2 days
  • Number of Revisions 2
  • Number of Pages 2

Frequently asked questions

5.0
1 review
100% Complete
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1% Complete
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1% Complete
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GO

Glen O.
5.00
Sep 6, 2025
Development work for a SaaS platform Mudassar is a diligent and capable developer who is an asset to any team.
He is responsive and communicative and will provide suggestions to help make things better.
He is able to quickly grasp an understanding of the project and if he is unsure of anything, he will perform research and due diligence before commencing the activity.
Muddasar H.Status: Offline

About Muddasar

Muddasar H.Status: Offline
Full Stack Developer | Ruby on Rails & React | SaaS Platforms
5.0  (1 review)
Lahore, Pakistan - 7:45 am local time
If you're building a SaaS product and need a full stack engineer who can own a feature completely, from billing to APIs to notifications, without needing constant direction, keep reading.

I'm a full stack engineer with two years of production experience in Ruby on Rails and React, shipping real features for real B2B SaaS products. At CoachVantage I built a complete SMS notification system using Twilio from scratch. Appointment confirmations, automated reminders at 48 hours, 24 hours, and 1 hour before, cancellations and reschedules, all fully automated with consent management, credit based billing, and retry logic. Zero double charges across the entire system.

I also fixed critical Stripe and PayPal billing bugs that were causing duplicate invoices for real customers, integrated Hasura GraphQL with a Rails backend cutting data fetch time by 45%, and reduced API response times by 40% using Redis caching under heavy production load.

I work across the full stack. I understand why features exist, not just how to build them. When I take on a project I own it completely. Right questions upfront, clear communication throughout, no disappearing mid project.

My core stack: Ruby on Rails, React, PostgreSQL, Stripe, Twilio, Sidekiq, Redis, REST APIs, GraphQL.
If your project involves any of these, lets talk.

Steps for completing your project

After purchasing the project, send requirements so Muddasar can start the project.

Delivery time starts when Muddasar receives requirements from you.

Muddasar works on your project following the steps below.

Revisions may occur after the delivery date.

Requirement Gathering

Collect API documentation, credentials, and integration goals.

Platform & Use Case Analysis

Understand your tech stack and how the API fits into your workflow.

Review the work, release payment, and leave feedback to Muddasar.