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You will get Full stack APIs .NET C#, Angular, Rect, AWS, Azure, GCP

Tuyen N.Status: Offline
Tuyen N. Tuyen N.
5.0
Preview image

Let a pro handle the details

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

Let a pro handle the details

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

Project details

What I do
 • REST APIs and Microservices: ASP.NET Core Web API, Entity Framework Core, Dapper, clean architecture, performance tuning, caching (Redis)
 • Frontend: React/Angular/Javascript
 • AI & RAG Systems: LLM integration, retrieval-augmented generation, vector search (Pinecone), chatbots, semantic search, video/audio transcription pipelines
 • Data Layer & Databases: SQL Server, PostgreSQL, MySQL, MongoDB, Firestore; schema design, indexing, query optimization, migrations, profiling
 • Security & Auth: OAuth2, OpenID Connect, JWT; secure API design and best practices
 • Cloud & DevOps: Azure, AWS, GCP; Docker and Kubernetes; scalable, cost-aware deployments; logging/monitoring
 • Background Processing: Cron jobs, worker services, scheduled tasks, resilient retries
 • Integrations: Stripe, SendGrid, Segment, GitHub; third‑party API integration
 • Multi-Tenant SaaS: Tenant isolation, shared resources, and lifecycle management
Programming Languages
JavaScript, ASP.NET, C#
Coding Expertise
Performance Optimization, Security
What's included
Service Tiers Starter
$99
Standard
$599
Advanced
$899
Delivery Time 1 day 5 days 7 days
Number of Revisions
123
Number of Pages
123
Design Customization
-
-
-
Content Upload
-
-
-
Responsive Design
-
-
-
Source Code
Optional add-ons You can add these on the next page.
Fast Delivery
+$99 - $199
Additional Revision
+$20
Additional Page (+ 1 Day)
+$50
5.0
8 reviews
100% Complete
(8)
1% Complete
(0)
1% Complete
(0)
1% Complete
(0)
1% Complete
(0)

GA

Guy A.
4.70
Dec 30, 2022
Backend developer (.NET/Azure)

RA

Roy A.
5.00
Dec 13, 2022
Expert Senior .Net Core Developer Excellent work by a very smart and hardworking programmer. A pleasure to work with Thanh. looking forward to working with you again.

MF

Marsh F.
5.00
Jan 20, 2021
Developer needed for CRUD WebApp with an MS SQL Server Backend Thanh is an excellent developer and business person. He did a great job working around my schedule to answer questions and deliver the exact application I requested. He speaks excellent English and was a pleasure to work with.

SR

Srikanth R.
5.00
Jan 4, 2021
.NET Developer Thanh was very proactive at his work, asking right questions and keen to improve the quality of the product.
Delivers work bug free. He is a dependable, regular and punctual developer.

DN

Dominic N.
5.00
Nov 11, 2020
Debug Asp.net Core Project
Tuyen N.Status: Offline

About Tuyen

Tuyen N.Status: Offline
AI Developer / RAG / Chatbots / LLMs / Senior .NET C#
5.0  (8 reviews)
Hanoi, Vietnam - 8:57 pm local time
AI Developer | LLM Engineer | AI Agent Developer | RAG Developer | OpenAI Developer | AI SaaS Backend

Top Rated Plus | $90K+ Earned | 10+ Clients | 3000+ Hours

I help startups and companies build production-ready AI applications using LLMs, AI agents, and scalable backend systems.

I specialize in building AI-powered SaaS platforms, agentic workflows, RAG systems, and high-performance APIs using .NET, OpenAI, and modern cloud infrastructure. My work focuses on turning AI ideas into real, scalable products.

If you need an AI developer who understands both LLMs and backend architecture, I can help design and build reliable AI systems that work in production.

Core Expertise
- AI Developer
Build AI applications using OpenAI, embeddings, vector databases, and LLM-powered workflows.

- LLM Engineer
Design and implement LLM features such as chatbots, copilots, AI assistants, semantic search, and automated reasoning systems.

- AI Agent Developer
Build autonomous AI agents and agentic workflows that interact with APIs, tools, and external systems.

- RAG Developer
Develop Retrieval Augmented Generation systems with embeddings, vector search, and knowledge retrieval pipelines.

- OpenAI Developer
Integrate OpenAI APIs for chatbots, copilots, AI automation, transcription, and AI-powered features.

- AI SaaS Backend
Build scalable backend systems and APIs that power AI applications and SaaS platforms.

- AI and LLM Stack
OpenAI, GPT models, embeddings, vector search, Pinecone, semantic search, AI agents, workflow automation, AI copilots, transcription pipelines

- Backend Development
.NET, C#, ASP.NET Core, Web API, microservices, distributed systems, event-driven architecture

- Databases
PostgreSQL, SQL Server, MySQL, MongoDB, Redis, Firestore, vector databases

- Cloud and DevOps
AWS, Azure, GCP, Docker, Kubernetes, CI/CD, scalable cloud infrastructure

- Security
OAuth2, OpenID Connect, JWT, Auth0

- Integrations
Stripe, Twilio, SendGrid, Segment, GitHub, Datadog

How I Work
- I focus on building reliable, production-ready systems with clear communication and structured delivery.
- Clear architecture and technical planning
- Milestones and frequent demos
- Clean, maintainable production code
- Scalable AI system design
- Reliable and on-time delivery

If you are building an AI product, AI SaaS platform, or LLM-powered application, I can help design and implement the system end-to-end.

Steps for completing your project

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

Delivery time starts when Tuyen receives requirements from you.

Tuyen works on your project following the steps below.

Revisions may occur after the delivery date.

Collecting Requirements

Implementation

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