Is your software ready for upgrade? 6 approaches to legacy system modernization

January 18, 2024
Is your software ready for upgrade? 6 approaches to legacy system modernization

Today, we witness continued technological advances, intensive competition, and a surging customer demand. Every two or three years, tech leaders need to reevaluate their business methods and align resources accordingly.

Software modernization is a strategic response to the ever-evolving market. This article explores key modernization approaches and shares time-tested practices of how to navigate the process effectively.

Software modernization: where to start

Development of new software is a complex process usually associated with common risks, such as budget constraints, product quality issues, and subpar functionality. So, building products from scratch may be a bold but risky strategy. Companies may choose to opt for software modernization instead in scenarios such as:

  • Critical data and a proven business logic
  • Time sensitivity and resource limitations
  • Security and compliance requirements
  • Risk mitigation with less disruptive workflows

Before you embark on the software modernization journey, make sure you have weighed the business perspective against the effort needed. Kick-start your modernization project with a thorough legacy system assessment. This evaluation walks you through the existing software landscape, pinpointing all the issues worth attention.

Your existing software needs modernization if:

  • The outdated functionality, hard to customize, scale, and optimize, poses risks to business competitiveness and customer satisfaction.
  • The tech stack is obsolete, unable to integrate with modern tools and platforms, leading to missed opportunities for innovation.
  • There is exposure to security vulnerabilities, compromising sensitive data, risking user privacy, and undermining data integrity.
  • Costs on maintenance—even making slight code changes—grew unreasonably high.
  • The rigid interface and features can no longer captivate customers, resulting in higher churn rates and impeding competitive advantage.
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As you grasp the foundation, let’s choose a modernization strategy that will work for you.

Key approaches to legacy system modernization

The most effective approach to software modernization is the one that fits your unique business case. So choosing the right strategy depends on several factors, such as the industry you operate in, the current workflows, a technology stack, etc. By doing so, you avoid undergoing unnecessary and costly processes.

Below, we enlist six proven modernization strategies and look into common use cases.

  1. Replatforming

The approach is known as ‘lift and reshape’. Replatforming involves migrating an app to a new platform with some optimizations made to prepare the system for a new environment.

Use case: A financial company uses legacy software to run mission-critical workloads. For better scalability, enhanced security, and reduced costs, the company decides to containerize its virtual machines, modernizing some app’s components for an improved performance.

  1. Rehosting

Unlike replatforming, the strategy is called ‘lift and shift’. Rehosting means moving an app from one environment to another without changing its codebase. The primary goal is to migrate quickly under tight deadlines and with minimal resources.

Use case: An e-commerce company runs its system that serves 10K+ users daily. Hosted on an on-premises server, the system cannot sustain increasing loads, leading to poor customer experience. So, the company decides to quickly migrate to a modern infrastructure (e.g., cloud) without changing the code, ensuring minimal downtime during the transition.

  1. Refactoring

Here, you make code changes to improve its structure and readability, while sticking to the core functionality. Additionally, refactoring is used to identify and eliminate idle features, streamlining maintenance.

Use case: A healthcare software provider has a complex application with the code hard to maintain and refine. This hinders the system's scalability and responsiveness to updates, increasing the risk of regulatory non-compliance. To mitigate the issue, the company refactors the code, focusing on its readability and maintainability. This effort streamlines future updates, enforces security, and ensures compliance.

Approaches to Legacy system modernization - Software modernization approaches

  1. Rearchitecting

The strategy entails changing the app's architecture to address scalability, performance, or other critical issues. It goes beyond refactoring, as you restructure the entire system to align with modern design principles.

Use case: With rapid user growth, an e-learning platform provider experiences scaling issues due to the underlying monolithic architecture. So, the company chooses to transition to a microservices architecture. This allows for better scalability, improved fault isolation, and the ability to deploy and update business-critical services independently

  1. Rebuilding

This involves redeveloping an app from scratch, preserving its specifications and functionality. So, you discard the current codebase to leverage modern development tools and practices.

Use case: A manufacturing company has a proprietary system for managing production processes. Due to an outdated, incompatible tech stack and a redundant codebase, the solution is hard to maintain, scale, and integrate with the necessary tooling. The company decides to rebuild the application from scratch, adopting modern development practices and technologies. The new system is efficient and easy to maintain, introducing streamlined integrations with management and analytics tools.

  1. Replacing

Replacing involves adopting new software available on the market or a custom-built solution to meet business requirements, while ensuring zero downtime for end users.

Use case: A retail chain relies on a legacy database to store product information and a broad customer base. However, the provider struggled with slow transactions, limited performance insights, and inventory discrepancies. Seeking operational efficiency, the retailer initiated a comprehensive database modernization, migrating to a modern, scalable database, while providing uninterrupted service.

Among the approaches to legacy system modernization, each catering to specific business needs and challenges, software reengineering stands out as an impactful strategy. Being relatively low-risk, it combines the refactoring, rearchitecting, and rebuilding techniques to optimize existing systems. Considering software reengineering first is particularly beneficial when dealing with complex applications.

Among the approaches to legacy system modernization, each catering to specific business needs and challenges, software reengineering stands out as an impactful strategy.
Read on

Software re-engineering best practices

The process can be categorized into three tactics: reverse engineering, restructuring, and forward engineering.

  1. Reverse engineering

This process entails examining the current software architecture. The key aspects include:

  • Codebase assessment
  • Documentation analysis
  • System behavior overview

Reverse engineering is particularly important when decoding complex legacy apps. The main purpose of this approach is to understand the original system design to reveal incomplete documentation or identify intellectual property.

  1. Restructuring

This tactic entails reorganizing software to improve its performance and maintainability. The restructuring process may cover the following:

  • Refactoring involves enhancing the codebase, making it readable and structured. This may also include removing obsolete code or duplicates, simplifying complex components, or employing development patterns for the system’s modularity.
  • Rearchitecting focuses on addressing issues, lays the foundation for scalability, and improves compliance with new technologies.
Approaches to Legacy system modernization - Reverse engineering vs. forward engineering

The main idea behind restructuring is to improve the existing design, optimize the system and make it easier to operate, and identify bugs.

  1. Forward engineering

This approach involves building and deploying a new software replica of the previous solution, with new requirements in mind. Based on modern design patterns, a new system uses advanced technologies and is capable of demonstrating unique features and unparalleled performance.

Software reengineering involves careful planning and resource allocation. At TYMIQ, we follow a proven methodology and a roadmap, tailoring the process to the project needs as we dive deeper.

Approaches to Legacy system modernization - The reengineering operating cycle

Software reengineering success hinges on multiple factors. With years of experience, we share our findings that may contribute to the project's effectiveness.

Solid reengineering expertise

Combining broad and narrow technical expertise is the key to successful projects. While breadth gives you a vision of reengineering efforts, depth allows for executing specific tasks with precision and accuracy. Thus, you maximize value and reduce the total cost of ownership.

Stakeholder involvement

Engage technical and business stakeholders from the outset for a clear goal understanding. This brings about transparency, builds trust, and improves communication at every step.

Modern collaboration techniques

Invest in your in-house team by fostering collaborative problem-solving. Consider using workshop-based methodologies such as Event Storming for team engagement and a holistic understanding of the software and domain.

At TYMIQ, turning complexities into success stories is what we do best. From total system reorganization to smooth transfers, optimized software architectures, new functionalities, and seamless integrations, we've got it covered.

Software modernization with zero disruption and infinite benefits. Tailored to your business.

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