Cloud-native developments have a lot of benefits. However, Mainframe is something that is still vital to a lot of enterprises because it is reliable, resilient, and you can trust its security. But as times are changing, using only the Mainframe is not ideal in today’s business models. So, it is time to take a step to the future and modernize your Mainframe to the cloud.

How to Modernize Mainframe to Cloud

What is Mainframe Modernization?

It is a process in which you upgrade your legacy mainframe systems and adapt to them instead of replacing them completely or using outdated mainframe systems.

You can stick to using outdated systems if you want to, but they are not cost-effective. Plus, the programming languages that are used to operate and maintain the Mainframe are getting older, and developers are not fond of using them. So, to get into the modern world and to ensure that you don’t miss out on anything in this digital revolution, modernizing your Mainframe is necessary.

Effective Strategies to Modernize the Mainframe

There are six primary strategies for modernizing your Mainframe. When you are updating your Mainframe, you may have to use a combination of these strategies.


As the name signifies, it means reusing the code that you have been using all this time. Codes, programs, and applications present on the Mainframe are mainly written in COBOL. You can start a cloud instance and use it as a Mainframe emulator. Then you can remove the codes, programs, and applications from the Mainframe and compile them in the emulator.

If you want quick results with very few upfront risks, then this might be the best strategy for you. The length of the project will be shortened drastically, and you will start saving money a lot sooner.

If you are using a Mainframe emulator hosted by AWS, it will open up a lot of opportunities. You can innovate more, like leveraging .NET, Java, and other APIs that you can integrate with programs and data that you couldn’t access before.

Rewrite the Code

As time goes on, newer programming languages come into the market, which aims to make the life of developers much easier. So, writing the Mainframe from scratch might be tempting. However, completely writing the code from scratch comes with its share of problems.

This approach comes with a lot of risks, and there is a high chance the project will fail. The overall process will become even more complex, costly, and time-consuming. Plus, the expense of writing a new code can become more than what you can save.

The best way is to both reuse and rewrites the code. So, move the applications that you have to the cloud-based emulator and migrate all your data to cloud-based databases. After that, you can put your focus on writing codes for modules using a multi-phased approach.

There are a lot of code transformation engines at your disposal that you can use to reduce your effort and risks. Although, if you write the code by yourself, it will allow you to freely make any changes in the code if you want to.


Sometimes, it is better to stop worrying about Mainframe entirely and replace it with third-party software, like a Software-as-a-Service (SaaS) application. There are SaaS applications developed as solutions for departments like finance, human resources, enterprise resource planning, etc. You can also find a lot of industry-specific applications which will act as a solution to problems related to mainframe modernization.

The best thing about using a third-party SaaS application is that you don’t have to worry about writing codes and maintaining them. However, their ability to customize is limited. Plus, it is costly to customize specifically for your company if a lot of organizations are using the same software.


Moving your Mainframe to the cloud opens up a lot of hosting options for you. Plus, since you will be able to access your Mainframe from any place around the world, you don’t have to worry if your code is located in a remote country.

Look for hosting platforms in less expensive locations. Then, you can shift your Mainframe to the cloud without worrying about changing the code. Plus, you will save a lot of money.


The latest platforms and operating systems allow the user to run applications in the cloud. So, you can modernize your Mainframe by moving the code to a different platform without changing it.


As time goes on, requirements change. So, you can rewrite your applications while keeping the latest requirements and business models in mind using domain-driven designs. This will not only modernize the technology that you own but also modernize your business processes.

By using a combination of these strategies, you can properly modernize your Mainframe to the cloud.

Things to Keep in Mind

There are a few things that you should always keep in mind when you are modernizing your Mainframe to the cloud.

  1. There is zero room for error. When you are migrating your Mainframe, make sure that there are no outages or interruptions. Any interruption can be devastating if it disrupts critical operations.
  2. Business stakeholders hate risks. When modernizing your Mainframe, if you implement too many risky measures, your stakeholders may get scared and stop the funding.
  3. Start working on use cases that will increase your business value through improvements in agility and flexibility. You must make sure that the efforts you put into modernizing the Mainframe gains credibility based on smaller and successful initiatives. Then you can move on to bigger ventures.

Final Thoughts

A lot of people still prefer to stay in their legacy systems. They are comfortable with their existing systems and don’t want to take the risk of modernizing. Mainframes have proven to be useful for decades.

But just because something works doesn’t mean it is the best. If you keep the ‘It works’ mentality, your business will become complacent, and you may fall back from your competitors in the future.

So, if you are modernizing your Mainframe, you need to step out of your comfort zone.

Modernizing your Mainframe to the cloud has a lot of benefits, and a lot of companies will eventually switch from legacy systems. So, you need to put in a lot of effort and face all complexities.