Legacy applications are software programs that have been operational for a very long time—some date back even a century. They are the mainstay of business operations, but they are also difficult and costly to maintain. For organizations to remain competitive, their legacy applications must be modernized. This is achieved by replacing or rebuilding the old systems with new platforms, languages, and architectural styles.
Modernizing legacy applications is difficult. It requires a well-thought-out plan that covers an organization's human, process, and technology aspects. This article provides a step-by-step approach to launching your legacy modernization project.
Before investing time and money into legacy application modernization services, you need to create a case that is robust enough. Key elements include:
What business challenges are your business organization facing that can be resolved by the modernization of legacy systems? Common drivers include:
Describe what the exact goals are you want to manage from a modernization attempt. For example:
Enumerate the expected business benefits that would be created based on factors like cost, revenue, customer experience, and risk. This helps to also earn support from the key stakeholders.
Once you have a solid business case, conduct a comprehensive assessment of your current application landscape. Key assessment areas include:
Catalog all systems, interfaces, and databases. Capture information such as the technology stack, data models, and integration points.
Diagram system components and data dependencies to identify risk areas. A legacy change or outage can ripple across connected systems.
Review system functionality against current and future business requirements. Identify functional gaps.
Examine code complexity, technical debt, and documentation. This impacts the effort required to modernize.
With assessment data, assign modernization priority levels to each application based on business value.
Next, analyze assessment findings to determine the right modernization strategy for each legacy app. Common strategic options:
Evaluate total cost, risk, and business impact when selecting strategies. Hybrid approaches are common across a legacy portfolio.
With legacy systems earmarked for modernization, it’s time to plan the migration:
Define target architecture vision across infrastructure, data, integrations, UX, and modular services.
Build out cross-functional teams combining both legacy domain experts and technical modernization resources.
Select transition methodology - big bang single cutover, phased rollout by region/users, or parallel run.
Identity risks around areas like data integrity, security, ops availability, and user adoption. Create mitigation plans.
Estimate efforts, build a project plan, and secure appropriate funding for the modernization program.
With a solid migration plan in place, now tackle executing the complex task of transitioning from legacy to modern:
Rethink and optimize business processes first before translating them into digital systems.
Engage with business and IT stakeholders early and often to manage change.
Utilize API-led connectivity to weave in modernized components into the existing environment.
Validate frequently - functionality, integrations, user scenarios and performance. Fix issues quickly.
Once the modern version is stable, retire legacy applications and infrastructure.
Legacy modernization is not a one-time affair. The new modern landscape is a dynamic environment that needs continuous investments and refinements.
By adhering to these instructions, organizations will be able to make their legacy systems that are outdated into modern and agile technology platforms that are delivering more value to the business. The journey involves a lot of patience to minimize the disruptions, however, the long-term benefits are great and worth the cost and investment.