Top 11 Legacy Modernization Companies for Delphi and VB.NET Systems 2026

Every release takes longer than it should. The team that understood the WinForms codebase retired two years ago, and the contractor who patched the Delphi billing module last spring is unreachable. Meanwhile a compliance deadline wants the platform on modern infrastructure, and the board wants cloud costs down, not up.

None of that means the system is bad. It means the system is old, and old means brittle hiring pools, slow onboarding for new engineers, and security reviews that flag ASP.NET Web Forms or VB.NET components nobody wants to touch. Picking a partner for this work means checking migration depth, proof of phased delivery without downtime, and whether the firm assesses before it rewrites.

How We Narrowed the Field

We started from published case studies and service pages, not sales pitches, looking for firms that name the actual legacy stack they touched: ASP.NET Web Forms, WinForms, WPF, AngularJS, Xamarin, Delphi, VB.NET. Vague “we modernize legacy systems” copy without a named framework or migration path got deprioritized fast.

We also went through customer feedback on Clutch to see how these firms are rated by the people who actually hired them, weighing that alongside scope and team structure. A firm with glowing marketing but thin, generic reviews ranked lower than one with modest volume but specific, technical feedback.

Team seniority mattered too. Modernization work punishes junior benches: someone has to read fifteen-year-old code and decide what’s safe to touch. We favored firms that could show certified engineering staff and a repeatable assessment phase, over shops that jump straight to a rewrite quote.

Where Legacy Systems Actually Break

Before comparing vendors, it helps to know what typically forces the modernization conversation in the first place.

Framework end-of-life pressure

.NET Framework, ASP.NET Web Forms and AngularJS no longer get the attention modern .NET, Angular or React ecosystems get, which means fewer libraries, fewer security patches, and a shrinking pool of engineers willing to learn them.

Hiring gaps for old stacks

Delphi and VB.NET developers are retiring faster than they’re being replaced, and WinForms or WPF specialists increasingly want to work in newer frameworks, which stretches hiring timelines for maintenance roles.

Cloud and compliance mandates

Fintech, healthcare and legal-tech buyers face growing pressure to run on Azure, AWS or GCP with modern identity and audit standards, something monolithic on-prem WinForms or WCF systems weren’t built for.

Fear of the big-bang rewrite

Teams delay modernization because a full rewrite threatens the roadmap and risks breaking a system that still generates revenue, which is why phased, module-by-module approaches matter more than they used to.

The List

1. Accenture

Accenture runs modernization as one line item inside broader digital transformation programs, backed by global delivery centers and industry-specific practices spanning finance, healthcare and the public sector. The firm brings deep bench strength for organizations with legacy estates that span dozens of applications and multiple business units at once.

Clutch shows Accenture at 5/5 across 7 reviews, a strong signal given the scale of engagements the platform captures.

Pricing sits at the premium end and runs on a custom-quote basis, consistent with Accenture’s positioning as a top-tier global consultancy.

Best for: large enterprises running multi-year, multi-system transformation programs with global delivery needs.

2. EPAM

EPAM built its name on deep engineering benches rather than consulting overlays, with named delivery centers across Central and Eastern Europe and a long history of .NET and Java modernization work for fintech and independent software vendors. The company pairs legacy migration with product engineering, so a Web Forms or WinForms estate can move toward a modern architecture without losing feature velocity.

Clutch lists EPAM at 5/5 across 2 reviews, a thin but clean sample given the firm’s scale.

Pricing runs at the premium tier on a quote basis, reflecting EPAM’s positioning among the larger engineering-first firms.

Best for: software product companies needing engineering-heavy modernization alongside ongoing feature development.

3. Leobit

Leobit works from a straightforward premise: assess the codebase and architecture first, then decide whether to refactor, re-platform or rebuild, instead of defaulting to a full rewrite. The firm has run more than 70 modernization projects on Microsoft and JavaScript stacks, including over 15 full platform migrations covering .NET Framework to modern .NET, ASP.NET Web Forms to ASP.NET Core and Angular, AngularJS to Angular, and Xamarin to .NET MAUI, alongside monolith-to-microservices work and WCF, WinForms, DevExpress, VB.NET and Delphi codebases.

One proof point stands out: a legal case management platform first built in the 1990s was moved from ASP.NET Web Forms to Angular one module at a time, while it kept serving government and legal users without a service interruption. That kind of staged delivery is exactly what CTOs weighing top legacy modernization companies for a live, revenue-generating system tend to need, since it avoids freezing the product roadmap during the transition.

The work is delivered by 78 Microsoft-certified engineers with more than 100 cloud projects completed on Azure, AWS and GCP between them. On Clutch, Leobit holds a 5/5 rating across 60 reviews, a sizable sample for a firm of its size.

Pricing lands in the mid-range tier on a quote-based model, positioned between boutique shops and the premium global integrators.

Engagements stay focused: one product or a cluster of related systems, not a sprawling multi-year integrator program, which suits teams that want a hands-on partner rather than a layered account structure.

Best for: mid-market software companies modernizing one core platform in stages without pausing the roadmap.

4. HCLTech

HCLTech’s modernization practice leans on its scale in application management and infrastructure services, useful for organizations that need modernization bundled with long-term operational support. The firm has a track record with large financial institutions and manufacturers moving mainframe-adjacent and .NET estates toward cloud-native architectures.

Its breadth is also its trade-off: engagements often assume a larger, longer-running program structure, which suits enterprise IT more than a single product team looking for a focused engagement.

Pricing sits at the premium tier, quoted per engagement, in line with HCLTech’s position among the larger IT services firms.

Best for: enterprises bundling legacy modernization with broader infrastructure and application management contracts.

5. IBM

IBM’s modernization work often centers on its own tooling, including watsonx Code Assistant for code transformation and long-standing mainframe and middleware expertise, making it a natural fit for organizations already invested in IBM infrastructure. The firm has decades of enterprise relationships in banking, insurance and government, sectors where legacy modernization carries heavy compliance weight.

That depth comes with scale assumptions: IBM’s engagement model tends to fit large, multi-year transformation budgets rather than a single mid-market product migration.

Pricing runs at the premium tier on a custom-quote basis, consistent with IBM’s positioning as a top-tier global technology and consulting provider.

Best for: large regulated enterprises already running IBM infrastructure who need modernization tied to compliance and mainframe-adjacent systems.

6. ScienceSoft

Founded in 1989 and long established in application modernization, ScienceSoft has built a wide portfolio spanning legacy .NET, Java and database re-platforming work across healthcare, finance and manufacturing clients. The firm publishes detailed technical case studies naming specific migration paths, useful for buyers who want to see methodology before a call.

Clutch shows ScienceSoft at 4.8/5 across 46 reviews, a solid volume that suggests consistent delivery across many small and mid-sized engagements.

Pricing sits in the mid-range tier on a quote basis, positioning ScienceSoft as an accessible alternative to the premium global firms.

Best for: mid-market companies wanting a well-documented, technically transparent modernization partner.

7. Keyhole Software

What sets Keyhole Software apart is its consulting-first, engineer-heavy model built around Java and .NET modernization for mid-market clients, without the layered account management of larger integrators. The firm tends to staff senior consultants directly on client problems rather than routing work through account teams, which shortens the distance between a CTO’s question and an engineer’s answer.

Its footprint is smaller than the global names on this list, which means less bench depth for simultaneous, multi-system programs but a tighter, more senior team per engagement.

Pricing runs at the mid-range tier on a quote basis, consistent with its positioning as a boutique technical consultancy.

Best for: mid-sized companies wanting senior consultants directly engaged on a focused .NET or Java modernization project.

8. Cognizant

Cognizant’s modernization practice draws on large industry verticals, especially healthcare, insurance and banking, where it pairs legacy application migration with broader digital and data initiatives. The firm has published work on moving mainframe-adjacent and .NET systems to cloud-native architectures at enterprise scale.

Engagements here typically assume a program-level scope, which fits organizations already running multiple parallel initiatives more than a single-platform migration.

Pricing sits at the premium tier, quoted per project, in keeping with Cognizant’s position among the larger global IT services firms.

Best for: large regulated enterprises pairing legacy modernization with wider digital transformation initiatives.

9. Infosys

Infosys brings a global delivery model to modernization work, with dedicated modernization platforms and partnerships across cloud providers, aimed at large enterprises managing sprawling application portfolios. The firm has a long history in banking and insurance, sectors where legacy .NET and mainframe-adjacent systems carry heavy regulatory weight.

Clutch rates Infosys at 5/5 across 5 reviews, a clean if modest sample relative to the firm’s scale.

Pricing runs at the premium tier on a quote basis, reflecting Infosys’s position among the top-tier global integrators. Programs here tend to run over years rather than months, better suited to organizations with portfolio-wide modernization mandates than a single product team.

Best for: large enterprises managing portfolio-wide legacy modernization across many applications.

10. Capgemini

Capgemini pairs modernization with its broader cloud and data consulting arms, often bundling legacy .NET and Java migration into wider enterprise transformation contracts. The firm has a substantial European and North American presence and a long history advising regulated industries on compliance-driven system upgrades.

Its scale means engagements are frequently structured as part of a multi-workstream program, which can mean longer ramp-up before code work actually starts.

Pricing sits at the premium tier on a custom-quote basis, in line with Capgemini’s position as a global consulting and technology firm.

Best for: enterprises seeking legacy modernization as part of a broader, multi-workstream transformation contract.

11. SoftServe

SoftServe built its reputation on deep engineering work across healthcare, fintech and energy, with named practices in cloud-native re-architecture and .NET modernization for mid-to-large software product companies. The firm tends to pair modernization with ongoing product engineering support, useful for platforms that need continuous delivery alongside the migration itself.

Clutch places SoftServe at 4.8/5 across 4 reviews, a small but clean sample.

Pricing runs at the mid-range tier on a quote basis, positioning SoftServe between boutique consultancies and the premium global integrators.

Best for: software product companies wanting modernization paired with continuous engineering support.

At a Glance

How to Choose Without Betting the Roadmap on the Wrong Partner

Ask what happens in week one. Does the firm start with a codebase and architecture assessment, the way Leobit and ScienceSoft describe in their published process, or does it jump straight to a rewrite estimate? A vendor that skips assessment is guessing at scope.

Ask whether the migration can happen module by module. A platform still serving live users, like the legal case management system Leobit modernized in stages, can’t tolerate a big-bang cutover; firms like Keyhole Software or SoftServe that staff senior engineers directly on the work tend to handle phased delivery better than heavily layered account structures.

Ask about team seniority, not just headcount. Cognizant and Capgemini bring scale, but scale doesn’t guarantee the person reading your fifteen-year-old Delphi code is senior.

Ask how pricing gets scoped, since every firm here quotes per project. And ask for evidence of the specific stack: WinForms, VB.NET, AngularJS, Xamarin. Generic “legacy modernization” language, without a named framework, is the clearest sign to keep looking.

The right partner is the one whose evidence matches your stack, your timeline and your appetite for risk, not the biggest logo on the page.

Frequently Asked Questions

How much do top legacy modernization companies charge?

Nearly all firms in this space quote per project rather than publishing rate cards, since scope depends heavily on codebase size and target architecture. Mid-range firms typically cost less than premium global integrators, but an accurate estimate requires a codebase assessment first.

How do I choose the best top legacy modernization companies for a live system?

Prioritize firms that assess the architecture before quoting a rewrite, and that can show phased, module-by-module delivery on a system that stayed live throughout. Also check team seniority and named proof points in published case studies, not just marketing language.

What services do top legacy modernization companies typically provide?

Most offer codebase and architecture assessment, framework migration, such as ASP.NET Web Forms to ASP.NET Core, cloud re-platforming to Azure, AWS or GCP, and ongoing engineering support after the migration. Some bundle this into broader digital transformation programs, while others focus narrowly on the technical migration itself.