You will get Custom REST API Integration & Backend Automation
Project details
Need to connect your system to Stripe, Amazon, Shopify, ERP, or any external API?
I implement secure, production-ready backend integrations designed for reliability, scalability, and long-term maintainability.
This service is ideal for:
• SaaS platforms
• E-commerce systems
• Marketplaces
• ERP / CRM integrations
• Payment & webhook-based systems
• Custom backend automation
What You Get
✔ Secure third-party API integration
✔ OAuth 2.0 / API key authentication
✔ Webhook subscription & verification
✔ Retry logic & rate limit handling
✔ Data transformation & sync automation
✔ Error logging & monitoring setup
✔ Clean, maintainable backend structure
I focus on backend-first architecture — not quick patches.
I implement secure, production-ready backend integrations designed for reliability, scalability, and long-term maintainability.
This service is ideal for:
• SaaS platforms
• E-commerce systems
• Marketplaces
• ERP / CRM integrations
• Payment & webhook-based systems
• Custom backend automation
What You Get
✔ Secure third-party API integration
✔ OAuth 2.0 / API key authentication
✔ Webhook subscription & verification
✔ Retry logic & rate limit handling
✔ Data transformation & sync automation
✔ Error logging & monitoring setup
✔ Clean, maintainable backend structure
I focus on backend-first architecture — not quick patches.
Programming Languages
PHP, HTML & CSS, JavaScriptCoding Expertise
Cross Browser & Device Compatibility, Localization, Performance OptimizationWhat's included
| Service Tiers |
Starter
$450
|
Standard
$950
|
Advanced
$1,990
|
|---|---|---|---|
| Delivery Time | 2 days | 4 days | 7 days |
Number of Revisions | 1 | 2 | 3 |
Number of Pages | 0 | 0 | 0 |
Design Customization | - | - | - |
Content Upload | - | - | - |
Responsive Design | - | - | - |
Source Code |
Optional add-ons
You can add these on the next page.
Fast Delivery
+$100 - $300
Add a second API
(+ 2 Days)
+$120
47 reviews
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This project doesn't have any reviews.
ta
tony a.
Apr 9, 2026
update?
Great service wonderful work always happy with this team. Good work. I will use you again.
ta
tony a.
Mar 18, 2026
Coding and Wordpress
Amazing experience every time! Very skilled, communicates well, and always delivers great work. I’ve used this seller multiple times and will continue to do so. Don’t let a few bad reviews fool you—this is someone who really cares about their clients.
ta
tony a.
Mar 14, 2025
You will get professional website with great features and look
Great job don’t look else where
MD
MD SAZID HASAN D.
Oct 9, 2024
Amazon Selling Partner API(for reports only) Postman Collection Setup for Japan Marketplace
A job well done!! And pretty fast!!
AR
Abdul R.
Sep 20, 2024
Stripe API Fix and Laravel Socket Integration
I am disappointed with this developer's performance. A 15-day project extended to nearly 3 months without completion. They struggled with small fixes, were often unresponsive, and frequently asked irrelevant questions. Despite multiple attempts to guide them, they failed to deliver the expected results and continuously requested payment before any significant progress.
About Hafiz Muhammad
Fractional CTO | CTO | Software Architect | SaaS, AI & FinTech
100%
Job Success
Multan, Pakistan - 11:38 pm local time
I help founders and companies make better technology decisions, lead engineering teams, modernize legacy systems, solve complex production problems, and build scalable technology roadmaps.
Fractional CTO | CTO | Solution Architect | Technology Consultant | Technical Due Diligence | Architecture Review | Engineering Leadership
I work at both strategic and technical levels—from technology strategy, architecture and engineering leadership to hands-on debugging, development, performance optimization, cloud infrastructure, and complex integrations.
For companies that don't need a full-time CTO, I provide Fractional CTO and part-time technical leadership to guide architecture, development teams, technology decisions, and production delivery.
Top 1% Stack Overflow Contributor | 2,800+ Reputation | 178+ Verified Solutions | 22+ Years Experience
I bridge business strategy and engineering execution—from technical discovery and architecture decisions to hands-on debugging, development, cloud infrastructure, and engineering leadership.
I’m especially valuable when you have:
• Legacy systems and technical debt
• Slow or unstable applications
• Database or scalability problems
• Complex APIs and third-party integrations
• Cloud/infrastructure challenges
• AI/LLM opportunities
• A development team needing senior technical direction
PROVEN IMPACT
Government / FinTech: Engineered a World Bank-audited asset and fuel infrastructure system supporting 5,000+ Pakistan Railways operations, reducing critical database queries from approximately 15 seconds to 200ms.
Enterprise AI: Built OCR + LLM document-processing pipelines that reduced manual invoice data entry by approximately 85%.
Legacy Modernization: Led Oracle → PostgreSQL and monolith → modular/microservices modernization initiatives, achieving approximately 3× runtime performance improvements.
Video / Real-Time: Head of Technology at Ourstube, architecting Node.js/NestJS services, WebRTC, payments, AdTech, video infrastructure, and distributed platform components.
WHAT I CAN LEAD
CTO / Architecture
• Technology strategy and architecture roadmaps
• Architecture and codebase assessments
• Technical due diligence
• Legacy modernization and database migrations
• Monolith → modular/microservices architecture
• Scalability and high-concurrency architecture
• Engineering leadership and mentoring
Backend / APIs
• Laravel / PHP
• Node.js / TypeScript / NestJS / Express
• REST APIs / microservices
• Event-driven architecture
• Third-party integrations
• Authentication, authorization and webhooks
Databases / Performance
• PostgreSQL / MySQL / Oracle / MongoDB
• Redis and caching
• Query/index optimization
• Database architecture and migrations
• Connection pooling and performance engineering
AI / LLM
• OpenAI / GPT integrations
• Claude / AI-assisted development
• OCR + document processing
• LLM-powered applications
• Structured AI outputs
• AI business automation
Cloud / DevOps
• AWS EC2 / S3 / RDS / Lambda / CloudWatch
• Docker
• GitHub Actions / CI/CD
• Nginx
• Production monitoring and troubleshooting
Payments / FinTech
• Stripe / Stripe Connect
• Subscription billing
• Payment webhooks
• Creator/vendor payouts
• Payoneer / Wise
• JazzCash / Easypaisa
SELECTED ENGAGEMENTS
Ourstube Media — Head of Technology | 2025–Present
Video/media platform involving Node.js/NestJS, WebRTC, payments, AdTech, video infrastructure, distributed services and real-time communication.
Global Connect ERP — 2024–2025
Oracle → PostgreSQL modernization and legacy-system decoupling toward modular/microservices architecture.
YetiScanner AI — 2024
AI-powered document processing and data-extraction architecture for Western European systems.
Pakistan Railways — 2021–2023
Mission-critical enterprise systems involving database optimization, security, performance and public-sector infrastructure.
WHY CLIENTS WORK WITH ME
I combine CTO-level strategic thinking with hands-on engineering capability.
You get:
• Architecture decisions tied to business outcomes
• Practical solutions without unnecessary complexity
• Clear communication with founders and engineering teams
• Hands-on debugging when implementation is required
• Focus on performance, reliability, security and scalability
• An actionable roadmap your team can actually execute
If your system is complex, slow, unstable, difficult to integrate, or approaching the limits of its current architecture, I can help identify the underlying problem and build the path forward.
Steps for completing your project
After purchasing the project, send requirements so Hafiz Muhammad can start the project.
Delivery time starts when Hafiz Muhammad receives requirements from you.
Hafiz Muhammad works on your project following the steps below.
Revisions may occur after the delivery date.
Architecture Review
Review API documentation and define integration structure.
Secure Integration Setup
Implement authentication, endpoints, and webhook logic.