20 Best Application Modernization Companies in 2026

Old software slows teams down. It costs more to fix, is hard to connect with new tools, and fewer developers know how to work on it. Application modernization companies help move that software to a current stack, cloud platform, or fresh design without breaking the business.

This list covers 20 companies, from small specialists to global giants. Noun Design is first. The other 19 are ranked by how directly their features target modernization work.

Application modernization updates legacy software so it runs on modern platforms, connects to current tools, and costs less to maintain. Common methods include rehosting, replatforming, refactoring, and rebuilding the app from scratch.

How We Ranked These Companies

We looked at what each company offers, not company size. Here are the factors we weighed:

• A dedicated modernization or re-engineering service
• Support for named legacy technologies such as COBOL, Delphi, WinForms, and mainframes
• Migration methods that keep live systems running
• Cloud, data, and AI support during the move
• Design and product skills for apps that need a full rebuild

Noun Design is our first pick for teams that want to rebuild an aging app into a better product. It is a digital product agency, not a pure modernization vendor. We say so in its entry below.

Quick Comparison Table

Rank	Company	Headquarters	Key Modernization Feature
1	Noun Design	Remote / global	Rebuild legacy apps as modern products
2	Corsac Technologies	Toronto, Canada	Migration off COBOL, Delphi, FoxPro
3	Reliqsy	Not disclosed	AI agents with zero-downtime cutover
4	Leobit	Austin, Texas, USA	WinForms, WCF, VB.NET migration
5	KITRUM	Not disclosed	Live-system migration, no downtime
6	N-iX	Valletta, Malta	Dedicated modernization service line
7	IBM	Armonk, New York, USA	Mainframe and AI-driven modernization
8	Radixweb	Frisco, Texas, USA	System modernization for regulated industries
9	Zoolatech	Miami, Florida, USA	Legacy service line plus team extension
10	Orases	Frederick, Maryland, USA	Legacy to scalable digital platforms
11	Aimprosoft	Cyprus	Legacy application modernization
12	DXC Luxoft	Ashburn, Virginia, USA (parent)	Trading platform and regtech modernization
13	Endava	London, UK	Core modernization with AI-native delivery
14	Accenture	Dublin, Ireland	Technology transformation at scale
15	Deloitte	London, UK	Legacy system transformation
16	PwC	London, UK	Digital core and ERP modernization
17	NashTech	United Kingdom	Legacy to cloud-native architecture
18	Kanda Software	Newton, Massachusetts, USA	Legacy conversion and cloud migration
19	Master of Code Global	Redwood City, California, USA	Legacy modernization plus AI development
20	Simform	Ahmedabad, India	Cloud, DevOps, and legacy migration

The 20 Best Application Modernization Companies

1. Noun Design

Website: noundesign.agency | Founded: 2019 | Team: Core team of 4+ | Location: Remote, global

Noun Design is a digital product agency covering UI/UX design, custom software, SaaS, mobile apps, and web development. That mix matters for modernization. Many old apps fail because the screens are hard to use, not just because the code is old. Noun Design redesigns the experience and rebuilds the software in one project, so you do not need to hire two vendors.

Teams wanting extra hands can add an offshore dedicated development team to their staff. This works well when an internal group knows the old system but lacks time to rebuild it.

Best for: Companies that want to rebuild an outdated app as a modern web, SaaS, or mobile product.

Watch out for: Noun Design is not a dedicated modernization vendor. It is a young agency with a small core team, so it fits focused rebuilds better than large mainframe programs.

2. Corsac Technologies

Location: Toronto, Canada | Reach: Canada, USA

Corsac is a legacy modernization specialist. It moves software off COBOL, Delphi, ColdFusion, Oracle Forms, and FoxPro. It also offers software audits and reverse engineering to help when no one on your team understands the old code. It has worked in healthcare, GIS, construction, banking, and nonprofit projects.

Best for: Teams stuck on rare or retired technologies.

Watch out for: Founding year and team size are not published. Ask for both during the first call.

3. Reliqsy

Reliqsy describes itself as a legacy modernization software company. Its framework uses AI agents to rewrite code, then tests that the new code behaves like the old. It also plans for zero-downtime cutover so users keep working while the switch happens. It covers application, data, and cloud modernization.

Best for: Teams that want AI-assisted code conversion with behavior checks.

Watch out for: Headquarters, founding year, and team size are not disclosed. Request case studies before you commit.

4. Leobit

Founded: 2014 | Team: 200+ engineers | Location: Austin, Texas, USA

Leobit runs dedicated software re-engineering and legacy migration services. It moves WCF, DevExpress, WinForms, jQuery, Knockout.js, Backbone.js, VB.NET, and Delphi apps to modern stacks. Delivery centers are in Ukraine, Estonia, Poland, and the UK. It is also a Microsoft Solutions Partner.

Best for: Microsoft and .NET-heavy applications.

Watch out for: Its strongest proof points are in .NET and web front-end stacks. Check fit if your app runs on something else.

5. KITRUM

KITRUM offers a dedicated legacy modernization service, with versions for healthcare software and e-commerce. Its method migrates live systems without downtime. It ranked 77th on The Americas’ Fastest-Growing Companies list for 2024.

Best for: Healthcare and online retail teams that cannot stop operations.

Watch out for: Its site doesn’t list headquarters, founding year, or team size.

6. N-iX

Founded: 2002 | Team: 2,400+ engineers | Location: Valletta, Malta (legal HQ)

N-iX runs an Application Modernization line inside its product engineering practice. It operates in 10 countries, including Poland, Ukraine, the USA, the UK, Sweden, Colombia, Bulgaria, Romania, and India. That spread gives you options for time zones and talent.

Best for: Mid-size to large programs that need many engineers.

Watch out for: A company this size may be more than a small project needs. The firm named a new CEO in September 2026. Ask how that affects delivery.

7. IBM

Founded: 1911 | Team: 264,300 (2025) | Location: Armonk, New York, USA

IBM Consulting handles legacy and mainframe (Z) modernization, cloud migration, and digital transformation. It also offers AI-driven modernization through watsonx and IBM Bob. Few vendors know mainframes as well as the company that built them.

Best for: Banks, insurers, and governments with mainframe systems.

Watch out for: Expect enterprise pricing and a formal process. Smaller teams may find it heavy.

8. Radixweb

Founded: About 1998 to 2000 | Team: 650+ | Location: Frisco, Texas, USA, and Ahmedabad, India

Radixweb offers System Modernization and Evolution as a core service. It focuses on legacy upgrades and digital transformation for healthcare, fintech, and other regulated industries. The company has more than 26 years of experience and offices in Canada, Australia, and Morocco.

Best for: Regulated businesses that need careful, step-by-step upgrades.

Watch out for: The founding year is approximate. Confirm it if you plan to quote it.

9. Zoolatech

Location: Miami, Florida, USA

Zoolatech runs a dedicated Legacy Modernization service alongside AI and ML, SaaS development, DevOps, and team extension. Its nearshore and offshore delivery model offers flexible staffing. The company has over 20 years of experience.

Best for: Teams that want modernization plus extra developers.

Watch out for: Founding year and team size are not disclosed.

10. Orases

Founded: 2000 | Location: Frederick, Maryland, USA

Orases turns aging technology into scalable digital platforms through its Legacy Modernization service. It also offers API and integration work, UI/UX design, data strategy, and AI consulting. These extras help when the old system must connect to new tools.

Best for: US companies that want a long-standing custom software partner.

Watch out for: Its footprint is centered in the USA, and team size is not disclosed.

11. Aimprosoft

Founded: 2005 | Location: Cyprus

Aimprosoft lists legacy application modernization as a service under Digital Transformation. It updates old systems and handles cloud migration. Its team spans more than 20 countries, including the UK, Spain, Bulgaria, Poland, and Portugal.

Best for: European clients who want a distributed team.

Watch out for: Team size is not disclosed, and modernization sits inside a wider service menu.

12. DXC Luxoft

Founded: 2000 | Parent: DXC Technology (Ashburn, Virginia, USA)

Luxoft modernizes legacy platforms for banking and financial services, focusing on trading systems. It also handles cloud migration and regulatory-tech upgrades. DXC bought Luxoft in 2019, and the site now uses the DXC Luxoft name. Delivery centers cover Europe, the Americas, and APAC.

Best for: Financial firms with complex trading or compliance systems.

Watch out for: Team size is not disclosed on its homepage, and it sits inside a larger parent company.

13. Endava

Founded: 2000 | Location: London, UK

Endava lists core modernization as a flagship strength. It pairs this with AI-native delivery and industry work in finance, healthcare, and payments. The company has 25 years of digital transformation experience.

Best for: Payments and finance companies that want modernization and AI in one plan.

Watch out for: Team size is not disclosed on its homepage.

14. Accenture

Founded: 1989 | Team: 779,000 (2025) | Location: Dublin, Ireland

Accenture is one of the largest IT consultancies in the world. Its Technology Transformation practice covers legacy modernization, digital engineering, and cloud and AI-enabled change in more than 120 countries.

Best for: Global enterprises with multi-country programs.

Watch out for: Costs and timelines match the scale. Small projects are rarely a fit.

15. Deloitte

Founded: 1845 | Team: 470,000 (2025) | Location: London, UK

Deloitte is a Big Four firm with a large technology arm. Its Cloud and Engineering practice handles legacy system transformation and migration. One public case study covers modernizing an airline passenger system. It serves clients in more than 150 countries.

Best for: Large organizations that need strategy and delivery from one firm.

Watch out for: Consulting-style engagements can be long and costly.

16. PwC

Founded: 1998 | Team: 370,000 (2024) | Location: London, UK

PwC offers Digital Core Modernization and Intelligent ERP. It connects cloud, data, and AI to business workflows. The firm traces its roots to Price Waterhouse (1849) and Coopers & Lybrand (1854).

Best for: ERP-centered modernization in large companies.

Watch out for: Its focus leans toward core business systems over custom app rebuilds.

17. NashTech

Location: United Kingdom

NashTech’s Modernise Technology service moves legacy systems to scalable cloud-native architectures. It also provides application management for solutions that have reached end of life. The company has been in business for almost 30 years.

Best for: Teams that need both a migration and ongoing support for retired software.

Watch out for: Founding year, team size, and delivery locations are not listed on its homepage.

18. Kanda Software

Founded: 1992 | Team: 501 to 1,000 | Location: Newton, Massachusetts, USA

Kanda converts legacy systems into modern architectures and handles cloud migration across private, hybrid, and public clouds. It has over three decades of custom software experience.

Best for: Mid-size firms moving to hybrid or private cloud.

Watch out for: Modernization sits under its broader Digital Transformation service, not a separate line.

19. Master of Code Global

Founded: 2004 | Team: 200+ | Location: Redwood City, California, USA

Master of Code Global pairs legacy systems transformation with AI development, built on more than 20 years of engineering experience. It built LOFT, an open-source LLM orchestration framework meant to bridge cloud-native architecture with existing enterprise systems during a migration.

The company covers technical debt assessment, microservices architecture design, and AI workflow automation across the modernization lifecycle, and builds with ISO 27001 practices for clients handling sensitive data.

Best for: Enterprises that want AI built into the modernization process from the start, not bolted on afterward.

Watch out for: Much of its public track record centers on conversational AI and customer-facing systems. Ask for examples closer to your specific legacy stack.

20. Simform

Founded: 2010 | Team: 845 | Location: Ahmedabad, India

Simform is a digital product engineering company. Its work includes cloud and DevOps engineering, legacy migration to the cloud, and data and AI/ML engineering. It has offices in Orlando, San Francisco, and Vancouver and is a Microsoft partner.

Best for: Cloud-first migrations that need strong DevOps.

Watch out for: Modernization is one part of a wider product engineering offer.

How to Choose the Right Modernization Partner

Checklist before you sign:

• Name your legacy stack and confirm the vendor has migrated it before
• Ask for a code and architecture audit first
• Choose a method: rehost, replatform, refactor, or rebuild
• Confirm how the switch happens without stopping live users
• Ask who owns the new code and the documentation
• Match company size to project size

Frequently Asked Questions

Is application modernization the same as cloud migration?

No. Cloud migration moves an app to a cloud host. Modernization can include that step but may also change the code, database, design, or whole architecture.

Do I need to rebuild my app from scratch?

Not always. Rehosting and replatforming keep most of the code. Refactoring cleans parts of it. A full rebuild makes sense when the code is too fragile or the user experience is badly outdated.

Can modernization happen without downtime?

Yes, in many cases. Vendors such as KITRUM and Reliqsy list zero-downtime migration as part of their approach. Ask each vendor to explain its cutover plan.

Should a small business hire a global consultancy?

Usually not. Large firms like Accenture, Deloitte, and PwC are built for enterprise programs. Smaller teams often get better value from specialists or product agencies.

Is Noun Design a fit for legacy mainframe projects?

Mainframe-heavy programs are better handled by firms like IBM. Noun Design fits projects where an aging app needs a new design, new code, and a modern platform.

Final Thoughts

The right partner depends on your stack, budget, and how much of the app you want to change. Specialists like Corsac, Reliqsy, and Leobit go deep on legacy technology. Global firms like IBM and Accenture handle huge programs. Noun Design is a strong pick when the goal is a better product, not just a moved one.