If your technology foundation is built on monolithic software, you’ll struggle to keep pace with a rapid influx of new projects. Your foundation must be solid enough to let you scale up as your business grows and evolves – legacy systems can only take you so far.
The single enormous code base you’ve relied on for years simply can’t scale when you’re duking it out in a dynamic, competitive landscape – regardless of your industry. The advantages of monolithic software evaporate to a point where you must re-evaluate its role. You also need flexibility and agility, which means adopting a microservices architecture is inevitable if you’re serious about embracing digital transformation and meeting your business goals.
Simple doesn’t always scale
Monolithic is as its name implies – all models and designs for software and services are kept under one roof, and all features and components reside in a single codebase, either on the server side or the client side.
An online movie booking service where everything happens in a single shot is an excellent example of monolithic software – the user login from the client side, authorization from the server, fetching of available seats, displaying them, and finally booking and storing the information in some database, is all driven by a single yet enormous codebase – this simplicity is one of the key reasons organizations stick with monolithic software:
- Initially, they can be relatively simple to develop and test
- It’s simple to deploy because all you need to do is copy the packaged application to a server
- It’s simple to scale horizontally by running multiple copies behind a load balancer
Despite its overwhelming simplicity, monolithic software struggles when it needs to scale, and the drawbacks are too hard to ignore:
- Monolithic software is limited by its size and complexity, slowing deployment cycles and lengthening time to market
- Applications get too large and too complex to fully understand – it’s tough to make changes quickly and correctly
- Monolithic software is tightly coupled – components depend heavily on each other, so scaling gets even more complicated when different modules have conflicting resource requirements
- Reliability is not its strong suit – one bug in any small module can potentially take down the entire process
A monolithic architecture ultimately runs the risk of becoming a large ship that can’t change course quickly – it’s too unwieldy to steer when an obstacle suddenly comes across its path. Agility and flexibility demand software that’s light and easy to maneuver.
Break things down to build up
With a monolithic architecture all of your eggs are in one basket, but a microservices architecture spreads them out by breaking down a relatively big problem into subproblems to solve them. The enormous codebase is gone because the big application is broken down into a set of smaller, interconnected services, which rely on each other.
The same online movie booking system can deliver the same service to end users powered by microservices in the backend. Users can still log in and perform a number of activities, but they’re all sub-divided. Each subdivision – a module – performs a specific function. The user sails through the whole process of booking the ticket as they always have, but the engine driving it is a lot different.
A microservices architecture offers many advantages over a monolithic approach:
- Specialization: Each module is specifically designed for one purpose alone – fault detection and isolation are relatively easy.
- Loose coupling: It’s far easier to recompose and reconfigure a microservices architecture to serve the purposes of different apps, allowing for fast, independent delivery of individual parts within a larger, integrated system.
- Better performance: Microservices deliver serious performance advantages and lower latency in most scenarios.
- Robustness: Microservices enable parallel development and employ a concept dubbed the “hard-to-cross-boundary”– although mistakes might get made at one level, the overall system is highly fault resistant because errors can’t creep across multiple levels.
However, a microservices architecture isn’t a cure all remedy it has its own set of drawbacks:
- Interdependence: With each module interacting and sending information back and forth, modules are naturally interdependent at a much higher scale – interoperability issues can pop up during testing and deployment.
- Increased inter-operational costs: Microservices are generally deployed on their own virtual machines or containers, which require a certain level of skill and expertise. Together with frequent container management requests, a microservices architecture can lead to higher costs.
Pick the right path forward
Now that you know the differences between a monolithic architecture and a microservices architecture, you have the information to select the one that aligns with your goals. Yes, a microservices architecture is more flexible and agile, but sometimes a monolithic architecture will fit the bill.
A microservices architecture is the better route when we need to break up the entire system into smaller components and design each one separately, and where it would be very difficult to do the same in one single module, if not impossible.
Going with microservices instead of monolithic software means weighing several factors ranging from time, budget constraints, team size and the scale we are eyeing – it boils down to whether we are looking at a system where scalability will soon be a big concern combined with the current system being too complex. If the answer is yes, it’s time to plot a transition to a microservices-based solution.
You can break monolithic code into microservices, but it depends on the use case – each one will vary significantly from the other, so keep in mind the following:
- Quick, independent service delivery is ensured where we have fast, independent delivery of individual parts within a larger, integrated system
- Sub-section efficiency means out of 100k lines of code, specific portions must be highly efficient and possess low latency, a feature that is easily available with microservices
- When vision for scalability is evident from the very beginning, we opt for such solutions wherein the whole team gets in the habit of developing smaller services right from the beginning
Think security and then accelerate
Moving from monolithic applications to microservices does have pitfalls – there’s an increased risk of security threats when services are dispersed. More ports are open, more application programming interfaces (APIs) are exposed, and authorization and authentication is more difficult because they happen at multiple levels. Controlled and authorized access to the APIs is essential. The principle of least privilege should be enforced to control access on a need basis – access to the internals of the services should be made off-limits to prevent human error.
Security concerns should not deter you from embracing microservices – you can adapt your security while embracing them to modernize your applications. Architech Accelerators not only provide the foundation and scaffolding to help you build and scale up applications in a cloud environment, but also integrate DevSecOps best practices so you can quickly deploy robust and secure cloud-native applications.
Microservices and containerization aren't categorically better or worse than traditional architectures—they're just different. You should base your decision on which approach is best for your organization based on how it aligns with your application modernization strategy, the capabilities of your team, and the type of digital solutions you need to develop to meet your business and user needs.