Modernizing Your Application: Planning for a Gradual Transition

Many organization looking to upgrade or replace a legacy application justifiably fear a long wait before they see a return on their investment. When your customers clamor for improvements, asking them to wait months—or years—to see changes may be asking too much.
It doesn’t have to be this way. Let’s explore how to achieve that modernization in steps that deliver value quickly, minimizing disruption to your users and organization.
Begin with APIs
As mentioned in the last article in this series, APIs (Application Programming Interfaces) play a crucial role. They act as the bridge between your existing application and the new one you’re building. Here’s how they empower an incremental approach:
- Separate Concerns: Existing or newly created APIs allow independent development of the front-end (user interface) and back-end (server-side logic) of your new application. This means you can prioritize which aspects to modernize first.
- Prioritize APIs based on Value: Focus on developing APIs that address the most critical pain points for your users and organization. You don’t need a complete API suite before launching the first phase of your new application.
- Minimizing Disruption: API development can often be done without impacting current users, ensuring a smooth transition.
Modular Modernization
In an ideal world, you’d be able to launch the new, modern version of your application with all features on day one. But that can mean an unacceptably long wait for your customers and your organization.
Instead, identify modules of your app that can function independently as an initial step. Here’s how to identify features for your initial rollout:
- Focus on Pain Points: Identify features that are causing the most frustration for your users and your organization. Addressing these first will generate immediate value.
- Delivering Value: Look for features that would provide significant benefits to both users and your organization. Modernization should not just replicate existing functionality; it should improve it.
- Building Excitement: Choose features that spark enthusiasm among stakeholders. This fosters momentum and support for the ongoing modernization effort.
Successful modernization efforts need organizational buy-in. By picking areas that have the most value to you and your customers will create momentum and enthusiasm for your endeavor.
Setting a solid foundation
Garnering organizational buy-in and excitement matter because the first module of the your app that you modernize will have the most overhead. You’re not just building that portion of your app, you’re setting up the foundation everything that follows.
This can involve:
- Thinking through the overall app design.
- Planning navigation and app flow.
- Selecting a technology stack.
- Creating a design system for design coherence and component reusability.
- Establishing coding standards and testing protocols.
Remember, this initial planning doesn’t require having all the answers upfront. But neglecting it can lead to challenges down the road. A little upfront work can save you a lot of headaches later.
Integrating the new with the old
One of the challenges of an incremental approach is managing user experience during the transition. The new and old application interfaces might create a temporary disjointed experience. Here are ways to minimize this:
- Leveraging iframes: Embed the new features within the existing application using iframes to provide a somewhat unified experience.
- Proxy Servers: Utilize proxy servers to serve the new application at familiar URLs within the old application, making the transition smoother.
- Transparency is Key: Communicate with your users about the modernization project. Your users will be understanding if they know what you have planned.
Step by step to modernization
Modernizing a legacy application can seem daunting. However, focusing on achieving incremental value through small steps makes the journey manageable. By delivering quick wins to users and stakeholders, you build momentum and support for the overall modernization effort.
Remember, you don’t have to navigate this journey alone. We offer free one-hour consultations to help you develop a strategy for modernizing your legacy application with minimal disruption.

Jason Grigsby is one of the co-founders of Cloud Four, Mobile Portland and Responsive Field Day. He is the author of Progressive Web Apps from A Book Apart. Follow him at @grigs.