You will get a Secure ASP.NET Core REST API — Web API, SQL & Swagger
Project details
Need a secure, well-built REST API your team can actually rely on? I design and build production-grade REST APIs in ASP.NET Core (C#) — clean endpoints, proper authentication, a solid database, and clear Swagger docs.
I'm a senior .NET backend engineer (5+ years) who has built and hardened APIs across property tech, ecommerce, and field-operations apps — including offline-sync APIs that stay reliable under bad connectivity. You work directly with me, the engineer writing your code. No agencies, no juniors.
What you can get:
✔ ASP.NET Core Web API with clean, RESTful endpoints
✔ JWT / OAuth authentication & role-based access
✔ SQL Server + Entity Framework Core
✔ Validation, error handling & Swagger/OpenAPI docs
✔ Third-party integrations & deployment-ready code
Pick a tier: API Starter (small API), Production API (auth + full CRUD), or Scalable API (integrations, tests & CI/CD).
Tell me what your API needs to do, and I'll reply with a clear plan before you order.
I'm a senior .NET backend engineer (5+ years) who has built and hardened APIs across property tech, ecommerce, and field-operations apps — including offline-sync APIs that stay reliable under bad connectivity. You work directly with me, the engineer writing your code. No agencies, no juniors.
What you can get:
✔ ASP.NET Core Web API with clean, RESTful endpoints
✔ JWT / OAuth authentication & role-based access
✔ SQL Server + Entity Framework Core
✔ Validation, error handling & Swagger/OpenAPI docs
✔ Third-party integrations & deployment-ready code
Pick a tier: API Starter (small API), Production API (auth + full CRUD), or Scalable API (integrations, tests & CI/CD).
Tell me what your API needs to do, and I'll reply with a clear plan before you order.
Programming Languages
ASP.NET, C#Coding Expertise
Cross Browser & Device Compatibility, Performance Optimization, SecurityWhat's included
| Service Tiers |
Starter
$120
|
Standard
$500
|
Advanced
$1,300
|
|---|---|---|---|
| Delivery Time | 3 days | 9 days | 18 days |
Number of Revisions | 1 | 2 | 9 |
Design Customization | - | - | - |
Content Upload | - | - | - |
Responsive Design | - | - | - |
Source Code |
Optional add-ons
You can add these on the next page.
Third Party Integration
(+ 2 Days)
+$150
Unit tests
(+ 2 Days)
+$100
Deploy
(+ 2 Days)
+$150Frequently asked questions
About Md. Ashraful
Senior .NET Backend Developer | ASP.NET Core, APIs & AI Integration
Dhaka, Bangladesh - 3:51 am local time
Need an ASP.NET Core backend that holds up in production — not just in a demo? Across 5+ years and 8+ enterprise projects, I've built and operated .NET systems — APIs, integrations, and deployments — in property technology, ecommerce, payments, and field operations, owning them end to end.
That includes a property-valuation SaaS (Australian market) serving 600+ users and an ecommerce platform handling 7,000+ daily logins — running on infrastructure I deploy and maintain myself. I don't just write endpoints and hand them off. I design the REST API, model the SQL Server data, wire up the integrations, deploy to the server, and stay on for the production issues after launch. You work directly with me — the engineer actually writing your code — not a sales rep or a rotating team of juniors.
Lately I've been adding an AI layer on top of solid .NET foundations: LLM and RAG features, ChromaDB-backed retrieval so an app can answer from your own documents, and AI-assisted automation that cuts manual work. Real backend engineering plus practical AI, in one person — which is exactly where a lot of businesses are heading in 2026.
What I can help you with
✔ ASP.NET Core & C# backend development
✔ REST / Web API design & development
✔ SQL Server design & query optimization
✔ Third-party & payment integrations (accounting, maps, calendars, real-time/WebSockets)
✔ AI integration — LLM, RAG, OpenAI, vector databases (ChromaDB)
✔ Ubuntu/VPS deployment, CI/CD & GitHub Actions
✔ Production troubleshooting, bug fixing & performance optimization
✔ Legacy .NET maintenance & modernization
My tech stack
Backend: C#, ASP.NET Core, ASP.NET MVC (Razor), Web API, Entity Framework, ABP Framework, REST, WebSockets
Database: Microsoft SQL Server — schema design, query optimization, working with large existing databases
AI & automation: LLMs, RAG pipelines, OpenAI API, ChromaDB (vector DB), AI-assisted development
Integrations: Xero/accounting, payment gateways, Google Maps, Google Calendar, IBM Watson, offline sync
DevOps: Ubuntu/Linux, Git, GitHub Actions, Docker, Nginx reverse proxy, CI/CD
Also: PHP (Laravel, CodeIgniter), Node.js, JavaScript, jQuery, basic Angular
A bit of what I've built
A production property-valuation SaaS (Australian market) on ASP.NET Core + ABP, serving 600+ users — valuation workflows, real-time updates, and accounting/third-party integrations
An offline-first field-data capture system with an ASP.NET Web API backend that syncs reliably under poor connectivity
Dealsorts — a smart ecommerce platform handling 7,000+ daily logins, which I built and deploy myself
ParkSharee — a parking booking/reservation platform I built end to end, currently in final pre-launch hardening
An open-source npm package I published and maintain, used by other developers
3 live projects currently running on my own self-managed Linux server — I own the deployment, configuration, and uptime
I'm a strong fit if you…
Have an ASP.NET Core app that's slow, buggy, or breaking under load and needs a senior hand
Need a reliable REST API or third-party/payment integration built right the first time
Want to add AI — chat, RAG over your own data, or automation — to an existing .NET system
Need someone to deploy, configure, and actually keep your app running in production
Are a startup or founder who wants one engineer who can own the backend end to end
How I work
I ask the right questions before writing a line of code, agree on a clear scope and timeline, share progress regularly, and test before I hand anything over. If something's wrong, I tell you early. My goal is a system you can build on — not a quick fix that breaks in three months.
Why clients work with me
✅ Production-ready, clean, maintainable code
✅ Clear, regular communication — you won't have to chase me for updates
✅ Fast responses and honest timelines
✅ I find the real problem, not just the reported one
✅ Post-delivery support and reasonable revisions
✅ Focused on long-term business value, not just closing a ticket
Availability
Open to part-time and full-time contracts, hourly or fixed price. I keep flexible hours and can overlap with US, UK, EU, and Australian business times, and I usually respond within a few hours.
Free 30-minute consultation
Choosing the right developer matters. Before any commitment, I'm happy to spend 30 minutes understanding your requirements, reviewing your existing system, and suggesting the best approach.
Send me a message or invite with a short description of your project, and I'll reply with a clear plan and an honest recommendation.
Steps for completing your project
After purchasing the project, send requirements so Md. Ashraful can start the project.
Delivery time starts when Md. Ashraful receives requirements from you.
Md. Ashraful works on your project following the steps below.
Revisions may occur after the delivery date.
Requirements & API Design
We confirm the endpoints, data model, and auth needs, and I share a short plan before building.
Data Model & Authentication
I set up the SQL Server schema with EF Core and implement secure authentication (JWT/OAuth).