Expert
Senior
Full-Stack .NET Developer
Turning complex business challenges into elegant, efficient solutions
25+
Years of
Experience
100%
Job Success
on Upwork
13+
years working
remotely
About
I'm
Jonathan Duncan
Welcome!
I'm a passionate and results-driven Full-Stack .NET Developer with 25+ years of programming experience. Specialized in crafting robust, scalable solutions for fintech startups and modern businesses, I have a proven track record of long-term engagements and successful project deliveries across diverse industries.
With a keen eye for detail and a commitment to excellence, I bridge the gap between business requirements and technical implementation. My expertise spans the entire development lifecycle, ensuring your project is in capable hands from conception to deployment. My approach ensures that the end product aligns with your business goals. My forte includes developing robust web applications, creating interactive database-driven websites, and implementing secure APIs.
Resume
Experience
Full Stack .NET Developer with Azure and Blazor for Fintech
Freelance
Worked on a brand new tech team, focusing on greenfield development
Utilized .NET 6/7, ASP.NET Web API, C#, Azure (DevOps, Blob Storage, CosmosDB, SQL Server, API Manager)
Developed with Blazor WASM front-end communicating with backend API server
Created B2B endpoints for third party clients via Azure API Manager
Worked with JavaScript, HTML5, CSS3, SQL Azure, and Git
Full stack .NET [6/C#] Developer with Azure and Blazor
Freelance
Led development team in maintaining and optimizing service architecture
Worked with C#, .NET Core 2.2 and 3.1, Angular 6+
Managed Azure cloud services including App Services, Functions, and DevOps
Utilized RavenDB 3.5
Azure Infrastructure and Scalability Consultant
Freelance
Reviewed and aligned codebase with production environment
Documented environment setup and deployment processes
Implemented code pipeline with automated builds and tests
Improved scalability of web application and database
Set up monitoring and alerting for web servers, databases, and infrastructure
Project Consultant for a webapp
Freelance
e-commerce solution with API Integrations
Freelance
Experienced ASP.Net ERP Web Software Developer
Freelance
C# Desktop Software Maintenance
Freelance
Ongoing management of existing .NET applications
Freelance
Update Features and Resolve Bugs on Existing Application
Freelance
Services
Tailored Solutions for Your Business Growth
Full-Stack Web Development
Crafting high-performance web applications that boost business growth and user satisfaction. From responsive e-commerce platforms to scalable web applications, I deliver solutions that drive results across devices and browsers.
20 ProjectsDatabase
I believe that a well-designed database is the backbone of any successful business. Whether you need to streamline your data management, enhance data security, or improve data accessibility, my database development & maintenance services are tailored to meet your specific needs.
10 ProjectsDesktop App Development
I specialize in developing powerful desktop applications that revolutionize how you work. With intuitive interfaces, robust functionalities, and seamless performance, I create tailored solutions that enhance productivity and elevate user experiences. Let's collaborate to transform your workflow and unlock your desktop's true potential.
8 ProjectsCore Competencies
Full-stack .NET development
Expertise in C#, ASP.NET Core, MVC, and Blazor
Cloud Services
Proficient in Azure, AWS, and GCP with emphasis on Azure
Database Administration
Experienced with SQL Server and CosmosDB
DevOps and CI/CD
Implementing efficient development and deployment processes
RESTful API Design
Creating and implementing robust API solutions
Secure Authentication
Implementing secure authentication systems
Skills
Technical Proficiencies
HTML
CSS/SCSS
Angular
.Net Framework
C#
ASP.NET MVC
ASP.NET Core
Blazor
SQL
.NET Core MVC
Azure DevOps
.NET Web API
Bootstrap
Microsoft SQL Server
Portfolio
Recent Achievements
FinTech Startup (2022-2024)
Developed an investment web application using Blazor WASM and .NET Core WebAPI, MSSQL. Implemented API creation, third-party API integration, and B2B endpoints via Azure API Manager.
E-commerce Platform (2020)
Developed an e-commerce solution with API integrations to sports data providers and printing companies, including customer data management and payment processing.
Testimonial
Don't just trust my word, look at What past clients have said
I've received high praise from clients, and they've highlighted my dedication, technical skills, and efficiency in communication. Here's what some of them have said about my work:
Upwork Client
"The freelance provided a very detail report and took the time to clearly explain the possible issue. He is very knowledgeable, understand our concern and came up with possible solutions to solve the issues with our web app. We would definitely work with him again."
Project Consultant for a webapp
Upwork Client
"Of all developer's Jonathan's work is the best; 1. Great technical skills, 2. Entrepreneurial, 3. Fantastic communication Skils. and 4. fair prices."
E-commerce solution with API Integrations - Adding a settings page
Upwork Client
"It has been an incredible/fantastic experience working with Jonathan and his team. Jonathan is very knowledgable and a fantastic full-stack engineer that can tackle any challenge from API solutions to Database and Cloud efficiencies."
Gooten API Integration
Upwork Client
"Jonathan is a fantastic Full Stack developer, who is curious and always looking to do what is best for the client and his/her customers. It has great programming skills and he is very proactive when additional research is needed"
Migrate Azure Database and ASP.NET Server to new Azure account
Upwork Client
"Very professional and highly skilled in his domains of expertise. We are very happy with this collaboration and I would highly recommend Jonathan."
Ongoing management of existing .NET applications
Upwork Client
"Jonathan is a top notch, detail oriented developer I recommend to anyone serious about a good quality/maintainable application!"
C# Desktop Software Maintenance
Upwork Client
"Jonathan is awesome... He has done really great work with our legacy systems and bringing them into a new environment. The only reason I'm ending this contract is to get him on a new contract. Really a strong coder, really easy to work with, and knows what's going on. Can't praise him enough."
Complete UI redesign project with ACE bootstrap theme
Upwork Client
"Jonathan is a detailed orientated and exceptionally strong SSRS developer that has an ability to figure out anything along the way. I will say Jonathan does best when the requirements are clear up front. Thanks again for your terrific work."
C# ASP.NET Developer
Upwork Client
"Jonathan was great to work with. He understood requirements quickly and was able to suggest improvements and ask good questions when things were unclear. I'll work with him again in the future."
Simple ASP.NET/C# and SSRS Web ApplicationWhy Choose Me?
- 'Top Rated Plus' developer on Upwork with a 100% job success rate
- Nearly 40 completed jobs on Upwork
- Proven ability to maintain long-term client relationships (multiple 3+ year engagements)
- Strong communication skills and ability to work across time zones
- Expertise in fintech, e-commerce, and enterprise development
- Consistent track record of delivering high-quality work on time and within budget
- Adherence to best practices
- Adaptable to various project sizes, from quick consultations to long-term development
Contact
Let's Discuss Your Project!
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