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Legacy Application Migration to Cloud - A 9-step Process

Last updated on
May 16, 2024


How to migrate legacy apps to cloud?

The process of migrating legacy systems to cloud can be condensed into 9 steps:

  1. First, you need to understand and assess the scope of migration.
  2. To make it more accurate, analyze the current infrastructure.
  3. Then, find or build a team with an accurate set of skills.
  4. In the fourth step focus on creating a detailed migration roadmap.
  5. Then, your team should rewrite or restructure code to leverage cloud-native services and architectures effectively.
  6. Migrate and integrate data.
  7. Test and validate, use automation.
  8. Kickstart the process of deployment.
  9. Optimize and collect user feedback.


Legacy Application Migration to Cloud - A 9-step Process

High costs of legacy systems

Quote about the high cost of maintaining legacy apps

This revelation from our 2024 State of Software Modernization report proves how important it is to introduce modern solutions that can reduce technical debt and fix the issues of legacy applications. Migrating them to the cloud can be one of the most effective approaches, and this article showcases this exact process.

The horrifying statistics behind redundant systems will be the main motivator for decision-makers to prepare migration strategies without disrupting their businesses. How do companies achieve this ambitious but tricky goal? Here’s our comprehensive, practical 9-step guide explaining every stage of transitioning a legacy app into the cloud architecture seamlessly.

Migrating legacy apps to cloud - A 9-step process

Step 1: Understand the scope

Before the migration process begins, it’s crucial to comprehend the scope of the project. Determining the size of the legacy application, its current functionalities, and the pain points it suffers from the most allows the project owners and managers to set the course of work and decide on priorities.

Legacy apps are outdated software systems that have been in operation for a significant period, which means that they are responsible for a large chunk of business logic, but also they are usually built on old technologies and architectures. Their main challenges include scalability, security, performance, and high maintenance costs. Moving to the cloud seems to be a viable solution for the majority of companies that don’t want to lose the app but want to accelerate its work.

Step 2: Assess and analyze

The initial stage of migrating legacy applications to the cloud involves conducting a thorough assessment of the existing infrastructure. This can include identifying dependencies, finding performance bottlenecks, determining compatibility issues, and naming any other problem that should be eliminated with migration. Manual audits can be supported by automated testing tools to help businesses gain as much insight as possible.

It’s important to also consider the shortcomings of the app, like proper data management or missing regulatory compliance. Migration to the cloud is an opportunity to add new functionalities, develop new safety measures, and tweak the system to meet legal requirements.

Step 3: Find the right team

The process of finding and hiring the right talent to handle legacy software is not easy. According to the 2024 State of Software Modernization report, usually, the internal software development team doesn’t know much about the old technology they have to work with. Additionally, they might not understand the overall value of migration efforts, which might delay the project. It’s crucial to hire both technical and non-technical crew to ensure a smooth transition that considers business objectives as well.

Change management is a completely different process than ordinary software development - that’s why it’s recommended to work with a seasoned partner who has experience in the legacy technology your app is built on and can prove their skills in migrating systems to the cloud architectures.

<span class="colorbox1" fs-test-element="box1"><p>Migrate your enterprise apps to the cloud to improve performance, scalability, and accessibility while reducing costs with the help of experts.</p></span>

Step 4: Create a roadmap

Prioritizing is necessary due to the complexity of legacy apps. It’s also essential to pick the most critical tasks to complete in the first place. The report we’ve mentioned proves that more than half of organizations prefer the incremental approach, where migration is done step by step, without increased risk of disruptions. To execute such a project, it’s important to build a roadmap that outlines the sequence of migration. It should consider factors such as business impact, resource availability, and required technical expertise.

The roadmap can also act as a guidebook for the team responsible for migration - it showcases what should be taken care of in the beginning and which tasks can be saved for later.

Step 5: Refactor and modernize

Refactoring legacy applications for cloud compatibility is imperative in the migration process. This involves rewriting or restructuring code to leverage cloud-native services and architectures effectively. Thus, the legacy to cloud migration is not only about moving the system from one infrastructure to the other. Some features will have to be rebuilt to match the new environment.

When modernizing legacy applications, it’s important to focus on scalability, performance, and cost-efficiency they can achieve thanks to changes. Additionally, businesses should pay attention to the capabilities of cloud platforms that can be allies in mitigating certain issues and reducing technical debt in the long run.

Step 6: Migrate and integrate data

Transferring data from on-premises architecture seamlessly is critical for legacy application migration to cloud storage. It’s also a great opportunity to address the consistency, integrity, and security of datasets in the business. This phase should be planned in detail to ensure minimal downtime and eliminate disruption to operations as much as possible.

Moreover, companies have to strategize the integration of the existing system with third-party services beforehand. Thanks to such a careful approach, they can maintain data coherence and interoperability. This is the crucial part of the whole process since that is the foundation of existence for every organization. Handling it with care and safety should be prioritized.

Step 7: Test and validate

A thorough checkup of all features, the environment itself, and connected external components is imperative to ensure the legacy app will work as it should when moved to the cloud. Brands need to conduct comprehensive performance audits, security assessments, and user acceptance testing to identify potential issues and fix them before the final implementation.

The quality assurance department can simulate real-world scenarios and try out the solution in various load conditions to validate the efficiency and reliability of the system. Also, they can use automation to perform some types of tests, like API, unit, and security tests.

Step 8: Deploy and release

When the software is ready, it’s time to kickstart the process of deployment. Migrating legacy applications to the cloud should happen when the user traffic is low. It also should have a dedicated team that won’t be occupied with other tasks during the release - they have to be able to react quickly to potential hiccups. It’s important to deploy the system step by step - if necessary, it might be done in parts over the course of a few days or even weeks (for large software).

If all the above-mentioned steps are taken care of with attention to detail, this stage shouldn’t be too problematic. However, it’s impossible to predict every potential disruption, so constant control is required.

Step 9: Optimize the system

Implementation of the legacy application to the cloud is not the final step of the whole process. Fortunately, there are plenty of cloud-native tools and services that support metrics monitoring to detect areas for improvement. Observing how the system operates in the new environment and collecting user feedback allows organizations to make decisions regarding resource allocation, performance optimization, and scalability.

Continuous refinement is essential to maximize the benefits of cloud migration and ensure the long-term success of the migrated system. Even though its infrastructure is modernized, it doesn’t mean the application will work perfectly. It should be constantly maintained.

<span class="colorbox1" fs-test-element="box1"><p>Read also: Legacy Systems Examples: How to Identify Them and Why You Really Should</p></span>

Risks in legacy application migration to the cloud

As an additional caution, we decided to create a list of risks to be aware of when performing legacy app migration to the cloud. Thanks to it, organizations can prepare themselves to handle all types of problematic situations:

  • Cost overruns: Inefficient planning and resource management can lead to budget overloads.
  • Data loss: Backup and recovery mechanisms should be prepared with care to decrease the risk of losing datasets during migration.
  • Compatibility issues: Legacy applications may not be able to work with third-party services or have troublesome dependencies.
  • Performance bottlenecks: Inaccurate usage forecasts can be responsible for downtimes and slow performance.
  • Service outages: Depending on the cloud provider of choice, sometimes vendors can experience problems that will influence how the system works.
  • Compliance: Companies should ensure data confidentiality and meet other guidelines provided by regulations like GDPR and CCPA.
  • Skill gap: Lack of expertise and organizational readiness may harm the migration process. Investing in training and upskilling of IT teams is a must.

Legacy app migration to the cloud done right

The process of transferring a legacy system to the cloud architecture is a complex operation that requires extensive knowledge, skills, and expertise. Even if your business has a talented IT team on board, they might not be able to handle all the tasks of the process. That’s why we advise working with a proven partner that has the right specialists and experience in migrating legacy systems.

Check out our cloud migration services and find out how we can help your legacy system thrive in the modern, digitized world.

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Olga Gierszal
IT Outsourcing Market Analyst & Software Engineering Editor

Software development enthusiast with 6 years of professional experience in the tech industry. Experienced in outsourcing and nearshoring market analysis. Our expert in presenting tech, business, and digital topics in an accessible way.

Leszek Knoll
CEO (Chief Engineering Officer)

With over 12 years of professional experience in the tech industry. Technology passionate, geek, and the co-founder of Brainhub. Combines his tech expertise with business knowledge.

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