Evolution of Architecture in Backend Engineering: From Old to New
The field of backend engineering has witnessed remarkable growth and transformation over the years. As technology advances rapidly, the architecture and methodologies employed in backend systems have also evolved significantly. We will explore the evolution of architecture in backend engineering, comparing the old ways with the new ones and highlighting the benefits and challenges of each approach.
Old Ways: Monolithic Architecture
The monolithic architecture was the prevailing approach in the early days of backend engineering, even had database bundled in the same process. This model built the entire application as a single, interconnected unit. The backend codebase encompassed all the functionalities and components required to run the application.
While monolithic architectures were relatively simple to develop and deploy, they suffered from several drawbacks. One significant challenge was the need for more scalability. As the application grew, maintaining and scaling the monolithic system became increasingly difficult. Monolithic systems follow vertical scalability while microservices based are horizontally scalable. Additionally, any bug or error in one component could affect the entire application, making debugging and maintenance time-consuming. Monolithic systems follow vertical scalability, while microservices based are horizontally scalable.
Talking of old ways, it becomes essential to talk about different tier architecture.
A 3-tier application architecture is a modular client-server architecture consisting of a presentation, application, and data tier. The data tier stores information, the application tier handles logic, and the presentation tier is a graphical user interface (GUI) that communicates with the other two tiers. The three tiers are logical, not physical, and may or may not run on the same server.
N-tier architecture divides an application into presentation, business logic, and data storage. It enables modular development, scalability, and easier maintenance, independently scalable each tier. However, it can introduce complexities in communication and data synchronisation between tiers.
Service-Oriented Architecture (SOA) focuses on creating independent, reusable services that communicate to perform specific functions. It promotes service composition and interoperability. SOA offers reusability, scalability, and flexibility, but managing service discovery and dependencies can be challenging.
New Ways: Microservices Architecture
The rise of microservices architecture marked a significant shift in backend engineering. Instead of building a single monolithic application, developers started breaking down the system into smaller, independent microservices. Each microservice focused on a specific functionality and could be developed, tested, and deployed independently.
Microservices architecture brought numerous advantages to backend engineering. Firstly, it enabled better scalability. As the application grew, additional instances of specific microservices could be deployed to handle the increased load, ensuring efficient resource utilisation. For example, suppose an e-commerce application experiences a surge in traffic during a sale. In that case, the microservice responsible for processing orders can be scaled horizontally by deploying additional instances to handle the increased load, ensuring optimal performance. Secondly, microservices allow teams to work in parallel, with each team responsible for a specific microservice. This improved development speed and facilitated easier debugging and maintenance, as issues were isolated to specific services. Thirdly with decent solution design in place, an issue in one part of the system doesn’t bring down the entire system
However, adopting a microservices architecture introduced new challenges. Communication between microservices became crucial, and implementing effective inter-service communication mechanisms such as APIs or message queues became essential. Managing data consistency across different services also required careful consideration. Additionally, the complexity of monitoring and deployment increased with the distributed nature of microservices. For example, need to setup correlated traces and logs along with metrics for each microservice to trace each request as they flow across multiple microservices.
Recent Trends: Server less Architecture and Event-Driven Systems
As technology continued to evolve, new architectural paradigms emerged in backend engineering. Two notable trends include server less architecture and event-driven systems.
Server less architecture takes the concept of microservices further by abstracting away the need for infrastructure management. Developers can focus solely on writing functions that respond to events without worrying about servers or scaling. Cloud providers handle the infrastructure, automatically scaling the functions based on demand. The server less architecture enables developers to build highly scalable and cost-effective applications for low scale codebase with the added benefit of pay-per-use pricing models. For instance, a server less function that handles image resizing can scale seamlessly as more images are uploaded to the application, ensuring efficient resource utilization without manual intervention.
On the other hand, event-driven systems focus on building applications around events and asynchronous communication. Instead of relying on synchronous request-response patterns, event-driven systems leverage message queues or event buses to decouple different components. This improves scalability, allows for real-time processing of events and enable loose coupling where you can add new features without affecting the other parts of the system.
Microservices and server less architectures facilitate parallel development, enabling faster delivery of features and easier maintenance. Event-driven systems promote real-time processing and responsiveness. For example, a team can develop the user authentication microservice while another team focuses on the payment processing microservice.
Talking of fault tolerance, a single bug can impact the entire application in monolithic architectures. With microservices, server less, and event-driven systems, issues are isolated to specific services or functions, making debugging and maintenance easier. For example, using replication, where multiple instances of a service are deployed across different servers or data centers, ensures that if one instance fails, another can take over without impacting the overall system’s availability.
It is important to consider the context and scale when choosing between microservices and server less architectures. Microservices are generally preferred at high scales, where the complexity and size of the system require a more granular and distributed approach. Microservices allow for independent scaling, easier maintenance, and better fault isolation. On the other hand, server less architectures are beneficial for smaller-scale applications or when rapid development and deployment are essential. Server less provides automatic scaling and eliminates the need for infrastructure management, making it ideal for event-driven or sporadically used functionalities. It’s worth noting that in modern application backends, a combination of microservices, server less components, and traditional monolithic approaches is often employed to create robust and flexible solutions that best fit the specific requirements of the application.
The evolution of architecture in backend engineering has paved the way for more scalable, maintainable, and efficient systems. Each approach has its own benefits and challenges, from the old monolithic architecture to the new microservices paradigm and recent trends like serverless and event-driven systems. As technology continues to advance, it’s essential for backend engineers to stay abreast of these architectural transformations, adopting the best approach that aligns with their application requirements and goals.