Deciphering the legacy software bottlenecks: How re-architecting reduces it?

Get a 360-degree view of how app modernization can help you reduce the bottlenecks of legacy software through re-architecting.

December 22, 2022
8 mins read
Last Updated December 22, 2022
legacy software rearchitecting

Deciphering the legacy software bottlenecks: How re-architecting reduces it?

Software architecture is like a car’s gearbox, with several components and moving parts working seamlessly to deliver business functions. Imagine all the gears and shafts coupled together. Failing to engage one gear will stop the car. Similarly, getting the software architecture right becomes key to ensuring continuous operations.

So, how to get the architecture right?

A simple answer is re-architecting the legacy software with a much-evolved architecture such as microservices. Netflix was able to minimize the frequency and severity of code errors and expand its services across 130 countries by re-architecting its legacy software.

But, the decision to modernize legacy software architecture takes work. For starters, you need to choose the right modernization approach. You can choose some approaches: refactoring, rewriting, re-architecting, and others.

Choosing the right approach requires analysis of multiple factors. So, here we are with a comprehensive take on different factors affecting the modernization of legacy software and how re-architecting is the best approach.

Simform is a digital product engineering expert and provides enhanced application modernization services to help businesses make legacy systems more agile  Connect with us today to re-architect your apps for better ROI!

What is legacy software re-architecting?

Legacy software re-architecting is a process of redesigning an existing software application or system to improve its functionality and scalability. This can involve the creation of new code, modifications to the existing codebase, or a combination of both.

Re-architecting can be done to speed up the development cycle, reduce maintenance costs, and improve overall performance. Software re-architecting can be done in various ways, depending on the project’s specific needs.

SOA vs. Microservices vs. Serverless: Which architecture is best?

Selecting the right way to re-architecture is essential. For instance, service-oriented architecture(SOA) divides the software into multiple services that work independently and communicate through communication protocols.

Another option is going serverless. This approach is granular, and development teams can create many self-contained units for the apps that communicate through APIs.

However, our focus will mainly be on microservices – a decoupled structure with several independent services. Re-architecting monolith to microservices can reduce the reliance on hardware and help integrate cloud services.

Benefits of legacy software re-architecting

Re-architecting legacy software provides a sense of freedom for businesses. Imagine customizing your app without worrying about downtime! However, customization is one of the many benefits that re-architecting provides.

Reduced cost of ownership

The total cost of ownership for legacy software increases as businesses scale. Re-architecting reduces the total cost of ownership through decoupled structure and cloud migration. For example, implementing microservices architecture through a containerization approach can help reduce costs.

Further, containers provide isolation of processes and OS-level virtualization that reduces business infrastructure costs, lowering the overall ownership cost.

Enhanced business agility

Re-architecting can help businesses rebuild architecture and add features as per market demand. Conventional monolith architecture is coupled, and adding features according to market demand affects the entire application.

Re-architecting the app to microservices means adding new features without disrupting the operations.

Better security monitoring

Monitoring the data at scale requires a massive effort, especially with a monolithic architecture. Re-architecting can help you overcome monitoring issues through the integration of cloud security monitoring tools like

  • Microsoft Azure Monitor
  • Amazon CloudWatch
  • Cisco Cloudcenter
  • Cloudflare WAF
  • Okta

Improved scalability and resilience

Re-architecting your applications can improve the scalability and resilience of systems by breaking it down into independent services. Legacy monolithic apps have a bounded approach where services lack extensibility. So, the entire app gets disrupted if you want to add more services or scale a single service.

If you re-architect the app into independent services, you can scale any service without disrupting the app. Re-architecting also improves the system’s resilience when you switch to microservices architecture.

All the services are decoupled, so the system has better resilience to failures. In other words, you can quickly recover failed services without affecting the app’s availability.

Integration of DevOps culture

The development and operations teams must collaborate to create efficient systems. By embracing the DevOps culture, you can create a collaborative environment where the development and operations teams work together.

DevOps breakdown the siloed approach and boosts collaboration. However, integrating the DevOps practices into your process flow requires flexibility. Monolithic architecture offers more flexibility as all the services are coupled.

On the contrary, microservices have independent services, which helps embrace the DevOps culture. In addition, organizations have autonomous teams working on independent services.

So, the development and operations team can focus on a single entity. Collaboration on several coupled services can be overwhelming if both teams work on a monolithic application. Instead, it’s far more efficient to have autonomous teams and embrace DevOps culture.

Like all other approaches, legacy software re-architecting has its benefits and risks. Therefore, you must consider all the risks of re-architecting before deciding to go for it.

Risks of legacy software re-architecting

Re-architecting legacy software can have several risks, including app disruption, performance issues, customer experience(CX) impact, and more.

Operational disruption

Re-architecting the application architecture can disrupt the operations and development lifecycle. For example, re-architecting 10-15 years old software requires detailed documentation of all the processes. However, essential documentation may need to be included due to non-existent code standards ten years back.

Besides the documentation, engineers who worked on the monolithic architecture may not be available for consultation. So, developers will need more time to understand the existing architecture, leading to delayed releases. Ultimately, operations may suffer downtime due to delayed releases, which is risky for many businesses.

The best way to avoid operational disruption during re-architecting is to have proper documentation for existing architecture.

Performance bottlenecks

The re-architecting process restructures the architecture and business processes. Consider an eCommerce application with an existing monolithic architecture. The increasing user base and scaling make the monolithic approach a bottleneck.

The reason is tightly coupled monolithic architecture. So, each time you add a feature or try to scale the app, it can cause performance issues as all the services are tightly coupled

Ecommerce monolithic architecture

So, you should take into account a few things before switching from a monolithic architecture to microservices, such as

  • Total number of services required for re-architecting
  • Performance issues while you run the monolithic app parallelly developing microservices
  • Database bottlenecks which are also monolithic at their core
  • Management of data transactions across microservices
Microservice architecture

Migrating from monolithic to microservices is not enough, as there can be performance bottlenecks if the implementation is not optimized. One way to ensure optimized microservice implementation is to leverage containerization.

Each container will have a separate database minimum configuration required to implement microservices. The best part is that you can run the containers and terminate them as needed.

Impact on CX

Legacy software re-architecting is not just about the backend. The front end of the software will also see changes impacting the user interface. Customers are used to your user interface, and when you make changes, they need to relearn it. Therefore, each interaction with the new app interface will be a learning curve initially for customers.

So, there is no denying that re-architecting the application can impact the customer experience. One possible solution is to integrate user feedback at each stage of the re-architecting process. You can leverage agile practices to ensure feedback integration with each iteration.

Lack of communication among teams

When you re-architect the application from monolithic to microservice architecture, some legacy services will run parallel to the newly developed services. So, you have to split the teams to work on either or both of them together.

Breaking your development team can lead to problems with collaboration and communication. One way to ensure human resource optimization is to analyze how many professionals you need to re-architect the app and run legacy components parallelly. Based on the analysis, you can manage human resources and, if required, hire skilled professionals.

Tech stack redundancy

One of the key reasons to re-architect legacy software is the redundant tech stack. However, the same tech stack redundancy can lead to issues like

  • Lack of compatibility with cloud architecture and modern services
  • High cost of replacing outdated technology
  • Need for skilled professionals
  • Resource requirements.

Such issues can risk the re-architecting project by increasing the time and resources needed to overcome them. So, you need to be mindful of the tech stack redundancy before re-architecting the legacy software and planning it accordingly.

Re-architect vs. Refactor vs. Rewrite: Why re-architecting stands apart?

Modernizing the legacy software requires consideration of different aspects like code structure, compatibility of new integrations, and system stability.

The refactoring approach involves minor changes to the code structure without changing its core functionality. It allows developers and programmers to reduce complexity.

On the other hand, rewriting is a hardcore overhaul where most of the legacy code is scrapped and rewritten.

Rewriting the code and re-architecting are two terms that are used interchangeably by many developers and programmers. However, re-architecting overhauls the code structure creating a new architecture for better efficiency, readability, and flexibility.

Re-architecting focuses on making the app code flexible and stable despite integration services or applications. So, if you want to add more functionality to your application by integrating services, choose to re-architect legacy software.

Here’s the comparison showing how re-architecting provides better service integrations, minimal bugs, system stability, and other benefits.

Differentiators Rewriting  Refactoring  Re-architecting
Code changes Complete overhaul Minor changes  Moderate changes
Changes in functionality New functionality  Code functionality remains the same Functionality can stay the same or change as per need
Integration of services Needs custom code for integrations Integrations are complex Facilitates integration of internal and external services
System stability Depends on code quality Lower stability Higher stability of the system

So, there is no denying that it is an attractive modernization approach for many businesses, but like every other approach, you need to analyze it.

Best practices to leverage legacy software re-architecting

Getting the implementation of re-architecting the legacy software right is essential. You can create a framework for re-architecting, reverse engineering, and code refinements.

Proof of architecture approach

Legacy software re-architecting requires running the new architecture and old architecture in parallel. So, ensure that your architecture approach works, or you will waste time and resources.

One way to have proof of architecture is to create a minimum viable version. For example, you can build specific services and test their efficiency. You can migrate from monolithic to microservices if the test results for specific services meet your pre-defined requirements.

Build a re-architecture framework.

You can build a legacy software re-architecture framework by

  • Identifying the core functionality of the legacy software system. It will help you focus efforts on improving specific areas and minimizing disruption or loss of data.
  • Determining the modernization path for your application. You can choose an approach from options like a replacement, refactoring, or others based on your desired objectives.
  • Developing comprehensive plan specifications for detailed plan documentation, including requirements documentation and system-level design diagrams.
  • Not all legacy code needs to be rewritten; sometimes, updating or modernizing certain features or components can be helpful. The re-architecture framework will enable you to identify such components.

Extract the legacy codes

Extraction is crucial to understand procedural abstractions. It allows you to analyze the existing structure for a redesign.

So, while extracting, analyze the source code on different levels of abstractions like system, program, module, pattern, etc. Also, evaluate old architecture and extract specifications from the source code to understand how the database connects with the front end or other processes.

Reverse engineer the extracted code

Reverse engineering is a process where engineers distill the abstract representations and reverse engineer the code. It allows you to create a new system design, especially on the architecture level.

However, reverse engineering has several purposes – auditing the system for security, API customizations, and feature addition. So, you need skilled professionals with knowledge of multiple programming languages, security best practices, and code refinement.

Further, you can also use tools like

  • Disassemblers convert the binary code into assembly code, extract strings,  import and export functions.
  • Debuggers to edit the assembly code and set specific breakpoints.
  • Hex editors to view binary code in a readable format and make changes as per software requirements.
  • PE and resource viewer to run the binary code on a Windows-based machine and initialize a program.

Refine the reverse-engineered code

Code refinement is a process of identifying, rectifying, and reducing redundancies and broken elements in the code. It involves

Code parsing for reverse engineering purposes and identifying key errors
Performing reverse engineering process to update the class model from selected files

Updating the class model and refining the code requires consideration of different functions. You can use the Algebraic Hierarchical Equations for Application Design (AHEAD) model for code refinement. It is a mathematical approach where an equation is used for each code representation of a service or program.

AXA ensured system stability with code refinement

AXA had more than 80 entities operational across 60 countries. Maintaining stability and reliability was key to AXA’s operations, so they needed to ensure no broken elements.

AXA’s teams embedded the cloud services like Amazon RDS, CloudWatch, and others using re-architecting. It allowed teams to build, test, and validate releases faster. Further, they ensured consistency across global landing zones by refining code and creating a standardized process.

Ash Shah, the Global move to the Cloud Director at AXA, says, “We can now develop products in days while historically it took months earlier.”

80 entities can now quickly leverage the global landing zones to build new features and apps using AWS services.

Visualize the changes

Legacy software re-architecting brings many changes to your system, and visualizing those changes allows you to control the new system better. Some visualization tools that provide a dynamic system analysis are:

  • Tableau provides hundreds of data import options and mapping capabilities for your systems. Further, it has an extensive gallery of infographic templates and visualizations to make your data easy to understand for the operational teams.
  • Infogram is a drag-and-drop visualization tool that allows even non-designers to create data visualizations with infographics, social media posts, maps, dashboards, and more.
  • D3.Js is a JavaScript library that allows the manipulation of documents using data for visualizations. However, it needs a little JavaScript knowledge. So, you can also choose alternatives like NVD3, which offers reusable charts for data visualization.
  • Google Charts is a free data visualization tool that you can use to create interactive charts. It works for both static and dynamic data outputs. You can use it for maps, scatter charts, histograms, and more.
  • FusionCharts is also a Javascript-based option that enables the creation of interactive dashboards for data visualization. It provides more than 1000 types of maps and allows you to integrate the maps and charts into popular JS frameworks.

Measure re-architecting success through metrics

  • Data visualizations do not add value if you don’t have specific parameters to analyze them. So, define the metrics for better visualization and system tracking. Some key metrics include:
  • Cyclomatic complexity is a quantitative measure of linearly independent paths in a code section. In other words, it shows the total number of different ways a code may execute to implement business logic.
  • Cohesion is a metric that allows you to measure the focus level of each class. If a class does not focus on the activity they are created for, it will create a confusing system.
  • Coupling allows you to measure how related or dependent two classes or modules are on each other. The higher coupling means code maintainability suffers, making it difficult for the organization.
  • Efferent and afferent coupling helps measure external and internal packages on which many classes depend.
  • Abstraction and instability allow you to measure the distance of the assembly’s sequence from the main sequence. Further, the distance less is the effectivity of assemblies.

A framework for re-architecting legacy software enables you to have stable and efficient systems.

Why do tech leaders re-architect into microservices?

Microservices is an architecture preferred by giants like Netflix, Amazon, and others. The question is – why do tech leaders choose microservices over monolithic architecture?

Microservices: the remedy to monolith legacy!

Microservices are only sometimes the first choice, but there is no denying that it acts as the remedy to monolith foes! Take an example of BBC’s re-architecting journey from distributed monolith to microservices architecture.

BBC caters to more than 50 million users registered on their platform. Each time a user tunes into a program on TV or there is an update on their favorite show, a personalized notification is sent to their devices. Such functionality and personalization require data collection, analysis, and categorization.

According to Blanca Garcia Gil, principal engineer at BBC,” We chose distributed monolith because BigData and microservices were not considered a possibility then. However, we learned it the hard way.

Further, BBC analyzed and processed data in batches. If a single batch of data suffered an error, it would cascade to other batches due to coupled architecture.

So, they decided to re-architect the architecture from distributed monolith to microservices. Choosing microservices over monolithic architecture helped them with three benefits,

  • Freedom of choosing different technologies for services
  • The flexibility of making changes to the code and adding new features
  • Isolating the failures and rectifying errors without disrupting the app operation

Microservices architecture allows organizations to add new features, business agility, cost reduction, better security, and extensibility.

Re-architecting the legacy software with Simform

Like BBC, many organizations leverage data analytics for improved business agility and personalization. However, legacy software architecture makes the integration of services difficult.

For example, an edutech company delivering data analytics to principals, board directors, and administrators needed to rebuild its BI platform within 12 months. So, it approached Simform to re-architect its legacy system.

We leveraged re-architecting and created a microservices-based architecture. Our engineers helped iResult re-architect and scaled the BI platform and deployed it across 2000 schools.

Similarly, if you want to re-architect the system and implement the microservice architecture, feel free to sign up for a 30-minute session with our experts!

Tejas is a Senior Tech Consultant at Simform excelling in mobile and server-side technologies, with extensive experience in working closely with startups and enterprises. His expertise in understanding tech has helped businesses achieve excellence over the long run.

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