Transforming ERP Systems: How QueryNow Accelerated Innovation with Microservices and the Strangler-Fig Pattern

Executive Summary

QueryNow, a forward-thinking technology firm, faced challenges with a legacy monolithic ERP that hindered developer productivity and slowed business innovation. By employing the strangler-fig pattern in conjunction with Microsoft Azure services, the company transformed its architecture. This case study walks through the planning workshop, service slicing, and data flows, while showcasing before-and-after performance improvements, including specific metrics. The clear benefits included faster deployment cycles, significant uptime enhancements, and a marked improvement in developer velocity.

Introduction

In an era where business agility is critical, legacy systems can become a bottleneck. QueryNow recognized that its monolithic ERP system was no longer capable of meeting market demands effectively. With modern cloud architecture technologies available through Microsoft Azure, QueryNow initiated a careful, step-by-step migration to microservices architecture using the strangler-fig pattern. This blog post details their journey, highlighting concrete examples, technical insights, and measurable performance benefits realized through the transformation.

Planning Workshop: Laying the Foundation

The migration from a monolithic structure to a microservices-based design is not a one-day project. QueryNow hosted a planning workshop that brought together architects, developers, and business stakeholders. The workshop's goals were to:

• Assess the Monolith: Map out critical components and dependencies within the existing ERP system.
• Define Service Boundaries: Identify functional areas such as billing, inventory management, and customer relationship management as candidate services.
• Set Priorities and Milestones: Agree on a phased approach to gradually replace monolithic functions with microservices without disrupting business operations.
• Establish Performance Metrics: Define success criteria around system uptime, response time, and developer velocity improvements.

This integrated approach ensured a unified vision, aligning technical feasibility with business objectives. Tools such as Microsoft Teams facilitated real-time collaboration, while Microsoft Whiteboard helped illustrate the transition roadmap.

Service Slicing and the Strangler-Fig Pattern

The strangler-fig pattern became the linchpin of the transformation strategy. Specific legacy ERP functions were incrementally re-architected into microservices hosted on Azure. By isolating services such as user authentication and order processing, QueryNow was able to gradually divert traffic away from the monolith.

Each microservice was designed around a single business capability, ensuring minimal code coupling and easier scalability. Azure Kubernetes Service (AKS) was used to containerize and orchestrate these services alongside Azure Service Bus that ensured reliable communication between components. This approach allowed uninterrupted business operations even while legacy components were still in production.

Data Flows and Integration

Data flow management was critical during the transition. QueryNow designed hybrid data flows to allow simultaneous operation of both monolithic and microservice components. Key aspects included:

• Data Replication: Utilizing Azure Data Factory to replicate data from legacy databases to Azure Cosmos DB, enabling gradual readouts from new services.
• API Gateways: Implementing Azure API Management to orchestrate calls between microservices and the remaining monolith, providing a secure, centralized entry point.
• Event-Driven Architecture: Leveraging Azure Event Grid to publish and subscribe to data changes, ensuring that the data consumed by new services was always current.

This dual data strategy not only maintained data integrity but also ensured seamless integration between legacy and modern components, ultimately resulting in drastic reductions in service latency and improved user experience.

Performance: Before and After

One of the most quantifiable benefits of the transformation was the measurable improvement in system performance. QueryNow monitored specific performance metrics such as response time, transaction throughput, and system uptime. Here are some before-and-after comparisons:

• Response Times: Prior to the migration, average response times for ERP transactions were in the range of 1.5-2.0 seconds. Post-transformation, leveraging microservices and Azure’s scaling capabilities, response times dropped to between 0.6 and 0.8 seconds.
• System Uptime: The monolithic system suffered from an uptime of around 95%. With the new architecture, uptime improved to 99.9%, largely due to the distributed nature of microservices and Azure’s built-in resiliency features.
• Transaction Throughput: Enhanced scalability allowed for a 40% increase in processed transactions per minute, enabling QueryNow to better handle peak loads during critical business hours.

These improvements were validated through performance monitoring tools, including Azure Monitor and Application Insights, which provided real-time analytics into system behavior and enabled proactive management of application health.

Impact on Developer Velocity and Business Agility

Perhaps the most significant benefit of this architectural overhaul was the dramatic improvement in developer velocity. Transitioning to a microservices model allowed development teams to innovate independently without affecting the entire system. Specifically:

• Faster Deployment Cycles: Microservices enabled a shift from monolithic month-long deployments to granular, weekly updates. This agile approach reduced time-to-market for new features by 50%.
• Focused Development: Developers can now work on isolated services, reducing complexity and overhead when addressing bugs or implementing enhancements. This led to a 30% reduction in bug resolution time.
• Improved Collaboration: Utilizing Azure DevOps pipelines streamlined continuous integration and delivery (CI/CD) processes. Teams experienced improved collaboration, leading to better code quality and predictable deployment outcomes.

Business stakeholders benefited as well, as the improved system allowed for rapid iteration based on user feedback, ultimately aligning IT strategy with evolving market needs.

Conclusion and Next Steps

QueryNow’s journey from a sluggish monolithic ERP to a nimble microservices-based architecture highlights how transformative the strangler-fig pattern can be when paired with powerful Microsoft Azure services. Key takeaways from this case study include:

• Rigorous planning and stakeholder alignment are essential for a successful migration.
• The phased approach of the strangler-fig pattern minimizes risk while maximizing incremental benefits.
• Leveraging integrated Azure solutions like AKS, Service Bus, and API Management can yield tangible improvements in performance and system uptime.
• Enhanced developer velocity and shorter deployment cycles offer clear competitive advantages in today’s fast-paced market.

For organizations facing similar legacy challenges, starting with a detailed assessment of your ERP’s components and establishing clear performance metrics is crucial. Consider engaging in a dedicated planning workshop, and deliberate on which parts of your system to slice into microservices first.

Next Steps: For further insights into migrating legacy systems, review the detailed documentation on Microsoft's microservices architecture on the Azure portal. Consider partnering with experts who have successfully navigated similar challenges to tailor the strangler-fig approach to your unique environment.

By embracing modern cloud technologies and a phased migration strategy, businesses can not only revitalize legacy systems but also set the stage for future innovation.