Dot NET Application Migration and Development Services Company

Modernizing .NET applications is a strategic priority. Many legacy .NET Framework versions are past their official support dates, leaving organizations exposed to unpatched vulnerabilities. Modern .NET versions are built for today’s needs: cross-platform deployment, cloud readiness, and high performance out of the box. Teams need microservices, containerized workloads, serverless functions, AI/ML features without needing to rebuild everything from scratch. CTOs, CIOs, and hiring managers modernize to give their teams the tools to move faster and work more securely.

Why Belitsoft?

With more than two decades devoted to .NET modernization, we’ve helped over 1,000 organizations achieve their technology goals - including the delivery of 200+ complex projects. After we deliver an MVP, nine out of ten customers choose to keep working with us.

Our modernization work is a targeted intervention aligned with the dominant business driver in each vertical, which is why the resulting gains meet sector-specific needs. For finance - it's security and compliance, for e-commerce - it's latency under load, for healthcare - it's data integrity and privacy.

The improvements after our migration and modernization efforts will be measurable - less manual work hours, lower page-load times, faster claim cycles, or higher orders per second. These KPIs are tracked before and after the cut-over, so the impact will be visible.

With Belitsoft, you’ll gain cross-platform deployment, cloud scalability, and stronger security - each of which ties directly to a business advantage like lower costs, higher uptime, or audit readiness.

Our .NET Migration Services

We provide a full-spectrum offering - architecture consulting to future-proof the design, performance testing to validate speed under load, cloud deployment to land you in Azure or AWS with best-practice pipelines, and ongoing support. Every layer of the stack is covered by experts. If all you need is a tight, migration-only engagement, we’ll deliver it.

Basic .NET Migration Services

We specialize in straightforward "lift-and-shift" migrations that move your applications from older .NET Framework versions to the latest .NET releases (such as .NET 8 or .NET 9) with minimal code changes.

We move your legacy software - whether it’s built on older versions of .NET - to the newest Microsoft .NET platform. The migration process is quick and cost-effective. We safeguard your data and keep downtime to a minimum. Our migration experts adjust each step to match your specific needs.

As part of the process, we update project files, upgrade infrastructure components, such as IIS or cloud-based services, assess environment configurations, and modernize web app deployment settings, so everything aligns with current best practices. 

Where data is involved, we migrate database schemas and stored procedures - whether you’re upgrading on-premises SQL Server or transitioning to Azure SQL - so your data layer remains fully compatible.

The end result - once the migration is complete, your application just works, delivering the same functionality you rely on, now running on fully supported, modern technology.

Enhanced .NET Modernization Services

Beyond simply moving code, this type of migration elevates your application.

We begin by upgrading the codebase to cross-platform .NET Core / .NET 8/9+ so you immediately benefit from the runtime’s performance and memory management gains - many organizations report 25-30% faster throughput after this step alone. 

While the upgrade is underway, we profile the app, tune hot paths, and harden security: HTTPS is enforced by default, authorization is refactored using ASP.NET Core’s modern policy model, and known vulnerabilities are patched.

If your legacy architecture limits agility, we refactor it - splitting monoliths into modular services or refreshing tiered designs - so the solution scales cleanly and is easier to maintain. 

At the same time, we can integrate new features or UX improvements from your wish list, ensuring the product that emerges feels both familiar and unmistakably better.

The result is an application that is faster, more secure, and cloud-ready - an upgrade in capability and value, not merely a change of runtime.

.NET Migration Service Delivery Models We Offer

Remote (Offshore) Team

Our offshore delivery model lets you tap into a global pool of seasoned .NET engineers, giving you enterprise-grade expertise at a lower cost than exclusively onshore teams. To make sure distance never dilutes quality, we build in robust communication rhythms - daily stand-ups, shared sprint boards, and overlapping core hours - so questions are answered promptly and priorities stay aligned.

Operating remotely also trims your overhead: you avoid extra office space and equipment costs while our teams handle the infrastructure. Throughout every sprint, collaborative tools and agile ceremonies keep progress transparent, pulling you into each decision loop and ensuring that "off-site" never feels out of sight.

Time-Zone Alignment

We can staff teams that work in your time zone, joining daily stand-ups and reacting to issues in real time. When using fully offshore talent for cost efficiency, we schedule guaranteed overlap windows. The result is a global team that feels local: quick hand-offs, instant feedback loops, and faster resolution of critical issues - no matter where the engineers are seated.

Engagement Models

Fixed-scope, one-off projects deliver a turnkey migration: we lock requirements, schedule, and price up front, then execute to meet the agreed-upon deadline and budget. This gives you maximum cost and timeline predictability while ensuring the application is fully migrated and ready for production on day one.

Ongoing partnerships extend the relationship beyond the initial cutover. After go-live, our team stays embedded as a strategic extension of your IT organization - handling iterative modernization, performance tuning, future .NET upgrades, routine maintenance, and rapid troubleshooting. This continuous engagement keeps the software evergreen and lets you evolve features at the pace your business demands.

Whether you need a single, predictable handoff or a long-term ally who shares your roadmap, we align our approach.

Need a team fast? 

We can spin up a dedicated, full-cycle team in just a few weeks, delivering approximately 170 hours per month of focused engineering capacity. 

If you already have developers in place, we integrate seamlessly as team augmentation - powered by a high-velocity recruitment engine that provides certified experts exactly when you need them. 

Engage us under an outsourcing model, and we take on the timeline and budget risk - freeing you to focus on the roadmap, not resourcing concerns.

.NET Applications Types We Migrate

Belitsoft offers end-to-end modernization across every part of a legacy application.

User interfaces

Desktop tools - whether WinForms, WPF, or console apps - are ported to the latest .NET so they run smoothly on Windows 11. If you have a VB.NET WinForms application, we can either move it intact onto .NET 8/9 to keep the familiar look and feel, or redesign the interface in WPF or Blazor for a more modern experience.

Web-based systems

We migrate classic ASP.NET Web Forms step by step into ASP.NET MVC or ASP.NET Core. Pages are replaced gradually, allowing the business to stay online during the process. If you want a new interface - React, Angular, or Blazor - we can add it on top of your existing logic, keeping functionality stable while improving the experience. The updated system runs on ASP.NET Core’s streamlined platform, giving you cleaner code, better performance, and room to scale in the cloud.

Backends

Legacy ASMX or WCF services are rebuilt as modern REST APIs or high-speed gRPC endpoints on .NET 8/9 and beyond. Background jobs that used to run as console or Windows services are migrated to .NET Worker Services - or Azure Functions, if you're moving to the cloud - to align with today’s DevOps and serverless models.

Databases

Whether you're upgrading an old SQL Server or switching to Azure SQL, we migrate your data and schema with full integrity checks. Mappings and stored procedures are updated and regression-tested, so your system picks up right where it left off - only faster, easier to maintain, and ready for what’s next.

.NET Migration Tools And Automation We Use

Our migrations are driven by automation and repeatable tooling. When using a Code First approach, every database change is scripted as an Entity Framework Core migration, so the schema evolves incrementally, can be replayed in any environment, and never relies on manual SQL. In Database First scenarios, we work from the existing database structure and apply updates directly using specialized tools to ensure consistency and traceability.

Before a single line is merged into "main", we run static code analyzers - the .NET Portability Analyzer, Roslyn-based rules, and custom security checks - to identify unsupported APIs, deprecated calls, or vulnerabilities.

Changes then flow through a CI/CD pipeline in platforms such as Azure DevOps or GitHub Actions: each push triggers clean builds, automated tests, and deployment to a staging slot. That feedback loop catches integration issues or performance regressions within minutes.

By the time we hand the project back, you get the fully automated build-and-release pipeline, which comes complete with green-to-green dashboards and one-click rollbacks.

.NET Migration for Large Enterprises

We deliver an end-to-end engagement that covers every phase - initial assessment, full-scale execution, and post-migration support - so you never manage multiple vendors.

We begin with an application-portfolio assessment and a pilot migration, identifying quick wins and hidden risks, and validating tooling in a controlled setting before any large-scale cut-over. This diligence de-risks the roadmap for the most complex enterprise estates.

Throughout execution, we coordinate tightly with your PMO and align to all internal compliance and security mandates, ensuring milestones, reporting, and governance dovetail with your existing processes. Because our bench spans databases, security, UI/UX, and cloud architecture, you get one-stop shopping - no need to stitch together separate specialists.

As the project wraps, we provide structured knowledge transfer and training so your teams can operate, extend, and modernize the platform long after we step back. 

.NET Migration for Cost-Conscious Organizations

Our offshore delivery model makes large-scale migrations financially viable without compromising quality. 

By tapping into global talent pools, we assign specialized .NET engineers to each task - often at significantly lower rates than fully onshore teams - and pass those savings directly to you. 

Mature processes, overlapping work hours, and disciplined communication rhythms eliminate common offshore pitfalls, keeping progress fast and expectations clear. 

This approach allows you to modernize mission-critical systems within tight budgets, rescuing projects that might otherwise have been shelved due to cost.

.NET Migration for Internal Development Teams

We serve as an on-demand extension of your engineering staff, stepping in wherever your migration hits a skills gap. Whether the sticking point is a VB6 module, an Entity Framework data layer, or a cloud uplift to Azure, our specialists plug directly into your workflow to tackle the hardest problems.

Collaboration is hands-on: pair programming sessions, structured code reviews, and quick-fire whiteboard problem-solving all happen in real time. Along the way, we can mentor your developers - explaining design choices, demonstrating modern patterns, and sharing practical tips.

By project close, you gain a fully modernized application and an upskilled in-house team equipped with the confidence and knowledge to own the codebase going forward.

Book a free migration assessment or request a no-obligation cost estimate today.