Legacy Modernization with Google Cloud: replace legacy systems step by step
Whether it's Lotus Notes, an Access database, Windows Server 2016, VMware or a home-grown application: with Google Cloud, there's a suitable path forward for almost every legacy system. We find it with you and implement it – planned and without a big bang.
- The right route for each system instead of one-size-fits-all
- From a 1:1 move to a rebuild with AI
- Migration in waves with parallel operation
In brief
Legacy modernization means replacing outdated applications, databases and servers with modern, secure solutions – without losing the knowledge built into them. Typical legacy systems in mid-sized companies are Lotus Notes, Access databases, Windows Server and VMware environments, Oracle databases and home-grown applications. GMinds works with you to define the right route for each system and implements it on Google Cloud.
of the companies surveyed have business-critical applications so outdated that they need to be renewed.
are considering replatforming to move existing applications to the cloud.
see a complete rebuild as an option.
* Source: Lünendonk study “IT modernization between legacy, cloud and AI” (2025, German-language)
Which legacy system, which route
For each of these legacy systems, Google Cloud offers suitable tools. The table shows typical routes – which one fits you is something we work out together.
| Legacy system | Typical trigger | Route with Google Cloud |
|---|---|---|
| Lotus Notes / HCL Domino | Few developers, high maintenance costs | Google Workspace for email and collaboration, AppSheet for Notes applications |
| Access databases and Excel macros | No secure multi-user operation, knowledge held by individuals | AppSheet, Cloud SQL, BigQuery |
| Windows Server 2012 and 2016 | End of support, no more security updates | Compute Engine, Migrate to Virtual Machines |
| VMware environments | Rising license costs | Google Cloud VMware Engine, Migrate to Virtual Machines |
| Oracle databases | High license and maintenance costs | Database Migration Service, AlloyDB, Cloud SQL for PostgreSQL |
| Home-grown applications (Java, .NET, Visual Basic, Delphi) | Knowledge is retiring, hard to extend | Cloud Run, Google Kubernetes Engine, Gemini Code Assist |
| Old file servers | Hardware needs replacing | Google Drive, Filestore |
| SAP ECC | End of mainstream maintenance | SAP Cloud ERP Private Edition on Google Cloud, SAP data in BigQuery |
How we modernize typical legacy systems
Replacing Lotus Notes
Email, calendar and collaboration move to Google Workspace. We rebuild Notes applications such as approvals, forms or databases with AppSheet. Archives that only need to be retained are stored in an audit-proof way.
Replacing Access databases
With AppSheet, Access databases and Excel macros become modern applications that run in the browser and on mobile phones. The data is stored securely in Cloud SQL or BigQuery instead of on individual computers.
Windows Server 2012 and 2016
With Migrate to Virtual Machines, servers move unchanged to Compute Engine – the fastest route when support deadlines are pressing. Windows Server runs there with the license included in the price or with your own license on dedicated hosts. After that, we modernize step by step.
VMware alternative
With Google Cloud VMware Engine, VMware environments keep running in Google Cloud without rework. Alternatively, virtual machines move directly to Compute Engine with Migrate to Virtual Machines.
Replacing Oracle databases
With Database Migration Service, Oracle databases move to AlloyDB or Cloud SQL for PostgreSQL. No Oracle license is needed for the target database.
Modernizing home-grown applications
We package established applications in Java, .NET, Visual Basic or Delphi into containers for Cloud Run or Google Kubernetes Engine, or rebuild them. Gemini helps you understand and translate old code.
Replacing file servers
Shares on old file servers move to Google Drive or – if applications need classic network drives – to Filestore.
SAP ECC
Mainstream maintenance for SAP ECC 6.0 ends at the end of 2027 (according to SAP). We support the move to SAP Cloud ERP Private Edition on Google Cloud and make your SAP data usable in BigQuery today.
SAP Data for AI →Five routes – the right one for each application
Move 1:1
Applications move to the cloud unchanged. Fast and low-risk.
Switch platforms
Databases and servers switch to managed services. The platform takes care of updates and backups.
Modernize
Applications are packaged into containers and scale without servers of your own.
Rebuild
A modern application is built with low-code or classic development.
Retire or replace
What nobody needs any more, we switch off. What off-the-shelf software does better, we replace.
Dates you should know
After the end of support, systems keep running – but they no longer receive security updates.
- 13 October 2026
Windows Server 2012 and 2012 R2
The last year of paid Extended Security Updates ended on 13 October 2026 (according to Microsoft).
- 12 January 2027
Windows Server 2016
End of extended support. Support for .NET Framework 4.6.2 ends on the same day. Microsoft offers paid Extended Security Updates (according to Microsoft).
- End of 2027
SAP ECC 6.0
Mainstream maintenance ends (according to SAP).
As of 5 November 2026, according to the manufacturers. Check the dates for your systems individually.
Understand old code before you replace it
Often the biggest hurdle isn't the technology but missing knowledge about old applications. With Google Cloud Modernize, Google brings together tools that use Gemini to analyze dependencies in Java and .NET applications and make concrete refactoring suggestions. Gemini Code Assist explains, documents and translates old code. A person always reviews the results.
Four steps to modern IT
Inventory
With Google Cloud Migration Center, we capture servers, applications and dependencies.
Define routes
For each system, we decide together: move, switch, modernize, rebuild or replace.
Implement
We migrate in waves and test each wave before the old system is switched off.
Operate
If you wish, we take over operations and keep optimizing costs and security.
The first step costs nothing
We review your environment read-only and show you in a results report where to start – free of charge and without obligation.
Let's look at your legacy systems together
- Classify affected systems and deadlines
- Outline the right route for each system
- Discuss a realistic timeline
