Microsoft .NET development
.NET and ASP.NET Core Development
Build, modernise and support business applications on Microsoft's application platform.
.NET is Microsoft's open-source platform for building web applications, APIs, services and desktop software in C#. We build new ASP.NET Core applications, upgrade older .NET Framework, MVC and Web Forms systems, and support .NET applications in production on Azure and other platforms.
What we cover
- ASP.NET Core web apps and APIs
- .NET Framework to modern .NET upgrades
- Entity Framework Core and SQL Server
- Blazor and Razor Pages
- Azure hosting and containers
- Testing and CI/CD
Requirement-led advice · Documented handover
- Advice based on your requirements
- Works with your existing stack
- Documented, maintainable delivery
What Are .NET and ASP.NET Core?
.NET is a free, open-source, cross-platform development platform from Microsoft. Applications written in C# run on Windows, Linux and macOS, in containers and in the cloud. Microsoft releases a new version every year, with Long Term Support (LTS) versions supported for three years, so keeping applications on a supported version is part of normal maintenance.
ASP.NET Core is the web framework in .NET. It supports MVC and Razor Pages for server-rendered sites, minimal APIs and controllers for REST services, Blazor for interactive web UI in C#, and SignalR for real-time features. Entity Framework Core handles data access to SQL Server, Azure SQL, PostgreSQL and other databases. Older applications built on .NET Framework 4.x, ASP.NET MVC 5 or Web Forms still run on Windows, but new features arrive only in modern .NET.
When .NET is a good fit
- You run on Microsoft Azure, SQL Server and Microsoft 365 and want one consistent stack.
- You need a strongly typed, high-performance platform for long-lived business systems.
- You have existing .NET Framework, MVC or Web Forms applications to modernise.
- Your team, or the team you hire, already works in C#.
What We Build With .NET
Typical .NET work, from new builds to keeping older systems healthy.
Business web applications
Portals, intranets and line-of-business systems.
REST and gRPC APIs
Services for web, mobile and partner integrations.
Framework upgrades
Move .NET Framework, MVC 5 and Web Forms apps to modern .NET.
Customer portals
Secure self-service portals with Microsoft Entra ID or other identity.
System integration
Connect ERP, CRM and SaaS systems through APIs and queues.
Background services
Workers, scheduled jobs and message processing.
AI-enabled features
Add AI features through Azure and Microsoft Foundry SDKs.
Support and maintenance
Fixes, security updates and version upgrades for live systems.
.NET Services We Deliver
Each piece of work has a clear output, so you know what you will receive.
New application development
ASP.NET Core applications and APIs built with tests and CI/CD.
Deliverables: source code, tests, deployment pipeline
Application assessment
Review an existing .NET system for risk, debt and upgrade options.
Deliverables: assessment report, upgrade roadmap
Modernisation and upgrades
Upgrade .NET Framework, MVC and Web Forms applications step by step.
Deliverables: migration plan, upgraded code, regression tests
Data layer work
Entity Framework Core models, query tuning and database migrations.
Deliverables: data model, migrations, performance fixes
Cloud and container hosting
Run .NET apps on Azure App Service, Container Apps or Kubernetes.
Deliverables: hosting setup, infrastructure as code
Ongoing support
Monitoring, security patches and annual .NET version updates.
Deliverables: support plan, release notes
The .NET Ecosystem We Work With
Frameworks and tools we choose from for each project.
Web and APIs
- ASP.NET Core MVC and Razor Pages
- Minimal APIs and Web API
- Blazor
- SignalR and gRPC
Data
- Entity Framework Core
- SQL Server and Azure SQL
- PostgreSQL
- Redis caching
Hosting
- Azure App Service
- Azure Container Apps and AKS
- Azure Functions
- IIS on Windows Server
Quality and delivery
- xUnit and NUnit
- Azure DevOps and GitHub Actions
- OpenTelemetry and Application Insights
- Static analysis
Listing a feature here does not mean every project uses it. We recommend what fits your requirements, skills, licensing and running costs.
How .NET Fits Your Stack
.NET applications usually run on Microsoft Azure with data in SQL Server and Azure SQL, and ship through Azure DevOps or GitHub pipelines. They often expose GraphQL or REST APIs to front ends and partners.
Older ASP.NET Development, ASP.NET Core and ASP.NET MVC topics are covered together on this page. For dedicated engineers see Hire .NET Developers, Hire .NET Core Developers and Hire C# Developers.
Implementation Considerations
- Plan upgrades around .NET support dates; LTS releases are supported for three years.
- Web Forms has no direct equivalent in ASP.NET Core, so those screens need redesign, usually in Razor Pages or Blazor.
- Upgrade in stages, keeping the application releasable, rather than in one big rewrite.
- Check third-party libraries for modern .NET support early.
- Add automated tests before large refactors so behaviour can be compared.
- Containerise only where it helps operations; App Service is often simpler.
How We Work With .NET and ASP.NET Core
The same four steps we use across our technology work, adapted to your scope.
Discover
Goals, users, constraints and the systems .NET and ASP.NET Core must work with.
Select
Confirm .NET and ASP.NET Core is the right fit and agree the architecture and scope.
Build and integrate
Deliver in short iterations with testing, reviews and documentation.
Operate and improve
Monitor, support and improve the solution as your needs change.
.NET and ASP.NET Core Questions, Answered
What is the difference between .NET Framework and .NET?
.NET Framework is the original Windows-only platform, now in maintenance. Modern .NET (formerly .NET Core) is cross-platform and receives new features every year.
Can you upgrade our ASP.NET MVC application to ASP.NET Core?
Yes. We assess the code, upgrade projects in stages, replace unsupported libraries and test behaviour at each step.
What happens to Web Forms applications?
Web Forms does not run on modern .NET. We plan a staged rebuild of the screens, often in Razor Pages or Blazor, while reusing business logic.
Which .NET version should we use?
Usually the latest Long Term Support release, unless you need a feature from a newer Standard Term Support release.
Can .NET applications run on Linux?
Yes. Modern .NET runs on Linux and in containers, which can reduce hosting costs.
Do you provide dedicated .NET developers?
Yes. See our Hire .NET Developers and Hire .NET Core Developers pages.
Building or Modernising a .NET Application?
Tell us about the application, its current version and your goals, and we will suggest a practical plan.
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