Ongoing Project

Transforming Legacy Systems for Scalability and Efficiency: A Case Study on Modernizing Healthcare Technology Architecture

About Our Client

Our client offers a specialized platform tailored to meet the unique needs of enterprise-level and mid-sized organizations in the therapy and rehabilitation sector. They specialize in various areas including:

• Patient Engagement and Communications: Focused on improving the patient experience.
• Clinical Documentation: Helps in maintaining accurate and comprehensive medical records.
• Revenue Cycle Management (RCM): Manages the financial aspects, including billing.
• Business Intelligence: Provides data analytics and insights.

Problem Statement

The organization in focus grapples with the limitations of an antiquated legacy system that hampers scalability and adaptability to evolving client needs. This outdated infrastructure not only restricts the company's growth but also poses challenges to operational efficiency and technological advancement. The need for modernization is imperative to meet the demands of a rapidly changing landscape and to ensure the system can scale elastically, integrate seamlessly, and operate with minimal overhead.

Modernization Highlights

• Micro-Frontend Architecture: Enables incremental adoption of a new technology stack, facilitating the scaling of frontend development and the formation of domain-specific, vertical teams.
• Serverless Technology: Employed across the board to ensure elastic scalability, reduce operational overhead, and enhance security and platform integration capabilities.
• Microservices Backend: Allows for the gradual decomposition and migration to a cutting-edge technology stack, aligning with modern best practices.
• Amplify Framework: Accelerates the adoption of core AWS services and aligns with industry best practices.
• Federated GraphQL Gateway: Serves as a unified query interface for client applications, irrespective of backend service distribution. It also acts as a transition point for migrating functionalities from the legacy to the modern stack.
• Low-Code Data Access: Utilizes velocity templates to simplify data access operations.
• API State Change Notifications: Driven by GraphQL subscriptions, these enable dynamic and reactive client applications while minimizing backend load.
• High-Performance Optimization: Includes CDN caching at the edge, API layer caching, and optimized read views through CQRS and DynamoDB Single-Table Design.

Architecture Design

Technology Stack

The technology stack employed in this modernization effort is meticulously chosen to address scalability, performance, and future-readiness. Each technology, service, or library serves a specific purpose, contributing to the overall robustness and efficiency of the system.

• Frontend Language
  • Typescript: Chosen for its type safety features, which enhance code quality and maintainability.
  • ReactJS 18: Utilized for its strong community support and rich ecosystem, enabling rapid development and deployment.

• Micro-Frontend Composition
  • Webpack Module Federation: Enables the seamless composition of micro-frontends, allowing for greater modularity and scalability.

• Frontend State Management
  • Context or Redux Toolkit (RTK): Used for efficient state management, offering flexibility in choosing between Context API or Redux based on project needs.

• Frontend Unit Testing
  • React Testing Library: Provides a robust framework for unit testing React components, ensuring code reliability.

• Website / Static Content Hosting
  • AWS S3: Offers reliable and scalable hosting solutions for static content and websites.

• Content Delivery Network (CDN)
  • AWS Cloudfront: Ensures fast and secure delivery of content across different geographical locations.

• End-to-end testing
  • Cypress: Provides a comprehensive solution for end-to-end testing, ensuring application reliability and user experience.

• Backend Language
  • TypeScript: Adopted for its type safety, enhancing code quality and maintainability.
  • NodeJS: Chosen for its event-driven architecture and non-blocking I/O, ideal for scalable applications.

• Compute
  • AWS Lambda: Utilized for serverless compute capabilities, reducing operational overhead and allowing for elastic scalability.

• Databases
  • AWS Aurora MySQL 8 (in progress): Being transitioned to for its high performance and compatibility with MySQL.
  • DynamoDB (new data sets): Used for new data sets, offering seamless scalability and low-latency data access.

• Event Streaming
  • AWS Kinesis: Employed for real-time event streaming capabilities, facilitating data ingestion and analytics.

• Queuing
  • AWS SQS: Provides reliable and scalable message queuing services, decoupling application components.

• Monitoring
  • Datadog: Chosen for comprehensive monitoring, offering insights into system performance and user behavior.

• API
  • GraphQL: Enables a flexible and efficient API layer, allowing clients to request exactly what they need.
  • AWS AppSync: Provides a fully managed service to make it easier to develop GraphQL APIs.

• API Testing
  • Jest: Utilized for robust API testing, ensuring the reliability of backend services.

• Centralized Logging & Log Analytics
  • Datadog: Offers centralized logging solutions, making it easier to debug and monitor system activities.

• Distributed Tracing
  • Datadog: Provides distributed tracing capabilities, offering insights into bottlenecks and performance issues.

• Load Testing
  • K6 (APIs): Used for API load testing, simulating multiple users to evaluate performance.
  • JMeter (End to End): Employed for comprehensive end-to-end load testing.
  • AWS Load Testing Solution: Provides a holistic approach to load testing, ensuring system resilience and scalability.

This comprehensive technology stack is designed to modernize the existing system while ensuring it is robust, scalable, and prepared for future challenges.

Specialized Implementations for Client-Specific Challenges

In addition to the robust technology stack, several key strategies and features have been specially implemented to address unique challenges and optimize the system for our client. These include a well-defined Branching Strategy to streamline development workflows, the adoption of Micro-Frontend architecture for modular and scalable frontend development, Single Sign-On (SSO) for enhanced security and user experience, and the use of Feature Flags to enable safe feature rollouts and A/B testing. Each of these elements plays a critical role in the modernization effort, and they will be elaborated upon in the subsequent sections to shed light on their significance and impact. Branching and Deployment Strategy We employ a Scaled Trunk-Based Development (STBD) approach to facilitate frequent delivery cycles, including new features and bug fixes. This strategy minimizes merge conflicts and supports continuous integration and code review, making it suitable for both small and large teams. Key to its success are a fully automated CI/CD pipeline, extensive automated testing, and Infrastructure as Code (IaC).

1. Branching and Deployment Strategy

We employ a Scaled Trunk-Based Development (STBD) approach to facilitate frequent delivery cycles, including new features and bug fixes. This strategy minimizes merge conflicts and supports continuous integration and code review, making it suitable for both small and large teams. Key to its success are a fully automated CI/CD pipeline, extensive automated testing, and Infrastructure as Code (IaC).

Feature Flags are used in conjunction with STBD to manage the rollout of new features safely. Our target for new stack deployments is a 2-week sprint basis, using a Canary Release process to manage risk. The classic stack will have less frequent deployments due to its limited automation capabilities, focusing mainly on scale and stability. We aim for a single active version of both the new and classic platforms in production, using feature flags to customize and mitigate risks in new deployments.

2. Feature Flags and LaunchDarkly Integration

Feature Flags serve as a pivotal component in our modernization strategy, allowing us to manage new feature rollouts and conduct A/B testing in a controlled environment. They provide the flexibility to toggle features on or off without requiring code changes, thereby reducing deployment risks.

Why LaunchDarkly?

We chose LaunchDarkly as our feature flag management platform for its robust capabilities, including real-time flag updates and comprehensive analytics. Its enterprise-grade features align perfectly with our need for a scalable and reliable solution.

Integration with GitHub Pipeline

LaunchDarkly has been seamlessly integrated into our GitHub pipeline, enabling automated flag management as part of our CI/CD process. This ensures that feature releases are tightly aligned with our development and deployment cycles.

LaunchDarkly REST API Wrapper Service

Due to the limitations of our legacy stack, which uses Delphi and PHP, we implemented a LaunchDarkly REST API Wrapper Service for both frontend and backend. This was necessary as no native Delphi client exists for LaunchDarkly.

Benefits of Using Wrapper Service

• Programming Language Agnostic: Allows for easy integration across different programming languages.
• Centralized Management: All LaunchDarkly secrets are managed in one place, simplifying security.
• Easier Version Management: Facilitates easy updates if LaunchDarkly changes its APIs.
• Feature Control: Provides the ability to selectively use features of LaunchDarkly.
• Metered REST API: Enables controlled access and the option to add caching.
• Centralized Logging and Monitoring: Simplifies debugging and performance tracking.
• No Rate Limits: Offers unrestricted access to the API, ensuring uninterrupted service.

This wrapper service not only bridges the technology gap but also offers several advantages in terms of security, manageability, and scalability.

3. Adoption of Micro-Frontend Architecture

In the ever-evolving landscape of frontend development, Micro-Frontend Architecture has emerged as a game-changer. This architectural style breaks down the frontend monolith into smaller, more manageable pieces, each responsible for a distinct feature or business domain. It allows different teams to work on different parts of an application, yet it brings everything together into a cohesive user experience.

How We Implemented Micro-Frontends

Our approach to Micro-Frontends is rooted in modular design and incremental development. We utilized Webpack Module Federation to enable seamless composition of micro-frontends, allowing for greater modularity and scalability. This has empowered our teams to work in parallel, accelerating the development process while reducing dependencies and bottlenecks.

Advantages of Using Micro-Frontends

• Scalability: Enables the frontend to scale along with the backend, accommodating more features and complexities over time.
• Team Autonomy: Allows individual teams to work independently on different features, using the technologies and approaches that best suit.
• Faster Time-to-Market: With teams working in parallel, features can be developed, tested, and deployed more quickly.
• Improved Code Quality: Smaller codebases are easier to manage, test, and debug, leading to higher quality code.
• Tech Stack Flexibility: Different micro-frontends can use different technologies, making it easier to adopt new frameworks or libraries.

Beyond the Basics

The adoption of Micro-Frontend Architecture has not just been a technical shift; it's been a cultural one. It has encouraged cross-functional collaboration, fostering a sense of ownership and accountability among teams. Moreover, it has paved the way for implementing advanced features like dynamic loading and a more personalized user experience.

By embracing Micro-Frontends, we've set the stage for a more flexible, scalable, and efficient frontend ecosystem, aligning perfectly with our modernization goals.

4. Implementation of Single Sign-On (SSO)

Single Sign-On (SSO) is a user authentication process that permits a user to enter one name and password in order to access multiple applications. In the context of our modernization efforts, implementing SSO has been a cornerstone for enhancing both security and the user experience.

Components Involved

• Desktop Client: The desktop application of the system.
• Web Client: Includes both old and new web applications.
• Auth Web App: A specialized component that handles various aspects of authentication and session management.
• Auth Proxy: Acts as an abstraction layer for Auth0, managing token refresh, caching, and expirations.

How SSO Works in Our System

The Auth Web App serves as the central hub for authentication, redirecting requests to the Auth Proxy. The Auth Proxy, in turn, is responsible for interacting with Auth0, storing sessions in DynamoDB, and sending session data back to the Auth Web App, which then communicates this to the relevant client - be it the old web client, new web client, or desktop client.

Why Auth0?

We chose Auth0 as our authentication provider for several compelling reasons:

• Scalability: Auth0 can easily scale to meet our growing needs.
• Security: Offers robust security features including multi-factor authentication.
• Flexibility: Provides a wide range of social identity providers, enterprise identity providers, and the option for custom integrations.
• Compliance: Meets various industry compliance standards, ensuring data protection.

Advantages of Our SSO Implementation

• Seamless User Experience: Users can switch between desktop and web clients without needing to log in multiple times.
• Future-Proof: Makes it easy to integrate new clients in the future.
• Error Handling: Gracefully manages error scenarios, enhancing reliability.
• Decoupling: Each client is decoupled from the authentication redirections, simplifying the architecture.

Results and Impact

The modernization effort has had a profound impact on both the client's operational efficiency and their ability to innovate. Below are some of the key results and impacts of this transformation:

In summary, the modernization effort has not only addressed the immediate challenges but has also set the stage for sustainable growth and innovation. The client is now better positioned than ever to meet the demands of an ever-changing healthcare landscape, making this transformation a resounding success.

Conclusion

The journey of modernizing our client's legacy system has been both challenging and rewarding, culminating in a transformative impact that extends beyond mere technological upgrades. Through a meticulously planned and executed strategy, we've successfully transitioned the client from an outdated, restrictive environment to a dynamic, scalable, and secure platform. This new foundation not only addresses the immediate pain points but also equips the client with the agility and flexibility required to navigate the future.

Key to this transformation has been the adoption of cutting-edge technologies and methodologies, from Micro-Frontend Architecture and Serverless Technology to specialized implementations like Single Sign-On (SSO) and Feature Flags. Each of these elements has contributed to creating a robust, efficient, and future-ready system.

The results speak for themselves: enhanced operational efficiency, fortified security, improved user experience, and a system architecture that's not just scalable but also adaptable to future technological advancements. Financially, the client has seen significant cost savings and revenue growth, making the modernization effort a strategic success.

As we conclude this case study, it's evident that the modernization initiative has been a pivotal turning point for the client, setting them on a path of sustainable growth and innovation. It serves as a testament to the transformative power of well-executed technological modernization, and we look forward to continuing this journey, exploring new horizons and possibilities.