Choose Micro Services Architecture if you are doing StartUps because the same modules could be used by many Apps simultaneously. In constract – When creating monoliths – the functionalities are highly coupled in one package and are harder to be used independently.
Monolith vs Micro Service Apps
Monoliths bundle all the functionality in a single package. The integration between modules are commonly implemented with Object Oriented, Aspect Oriented Design Patterns and Architectures.
While monolithic applications have their advantages, they also come with certain disadvantages, especially when it comes to reusability and scalability. Here are some drawbacks associated with reusing a monolithic app.
Lack of Modularity
Monolithic applications are typically built as a single, tightly-coupled unit. This lack of modularity can make it challenging to reuse specific components independently without affecting the entire system.
In Contrast – Microservices are designed as small, independent services that focus on specific business capabilities. This modularity allows for easier development, testing, and maintenance of individual services without affecting the entire system.
Reusing components from a monolithic application may limit flexibility in terms of technology stack or deployment options. Monoliths often rely on a single technology stack, making it harder to adapt to evolving technologies or integrate with new tools.
In the same time – each microservice can be developed using its own technology stack, depending on the specific requirements. This flexibility allows developers to choose the most suitable tools and programming languages for each service, promoting innovation and adaptability.
Scaling a monolithic application can be more challenging compared to microservices. With a monolith, you will need to scale the entire application, even if only a specific module or feature requires additional resources.
The good point of this is – it forces the developer to squize the performance with additional software patterns – without relying on new machines. The bad is – when it comes to the need of new instances of the app – it will be full and not – the micro module that is getting demand.
Microservices can be independently scaled based on demand. This enables more efficient resource utilization, as only the services that require scaling need additional resources. This is particularly beneficial for handling variable workloads.
Components within a monolithic application are often tightly coupled, creating dependencies between different parts of the system. This can make it difficult to extract and reuse individual components without extensive refactoring.
In Contrast – Each microservice can have its own database or data store, allowing for decentralized data management. This can improve data autonomy, reduce contention, and enhance data consistency for specific services.
Limited Reusability Across Projects
Reusing components from a monolithic app may be less practical across different projects with diverse requirements. Monoliths are often tailored to specific use cases, and extracting reusable components for general-purpose usage might require significant effort.
Maintaining and updating a monolithic application can become complex as the size of the codebase increases. Small changes may have unintended consequences across the entire system, making maintenance more challenging.
Microservices enable easier maintenance and updates. Teams can focus on specific services without the need to understand or modify the entire codebase. This reduces the risk of unintended consequences during maintenance.
Since microservices operate independently, a failure in one service is less likely to impact the entire system. This isolation enhances fault tolerance, resilience, and the overall reliability of the application.
Monolithic applications may have longer development cycles. One reason for this may be – changes to method interfaces may need to be applied to the entire codebase. This can slow down the development process compared to more agile and modular architectures. Where the interfaces are hidden behind Messaging Services Like Kafka or Docker or over REST this coupling is moved to a messaging contract and not to code linking.
Microservices facilitate agile development practices by allowing smaller, cross-functional teams to work independently on different services. This leads to faster development cycles, quicker testing, and more frequent deployments.
Microservices support continuous integration and delivery (CI/CD) practices, making it easier to deploy updates and new features. This agility is crucial for responding to changing business requirements and staying competitive in dynamic markets.
You often develop a Monolithic application using a specific technology stack. Reusing components from such an app may result in technology lock-in, making it harder to adopt new tools or frameworks that may be better suited for certain tasks.
Microservices allow the use of different database technologies for different services based on their specific requirements. This approach, known as polyglot persistence, ensures that each service uses the most suitable data storage solution.
You could create each microservice using its own technology stack, depending on the specific requirements. This flexibility allows developers to choose the most suitable tools and languages for each service, promoting innovation and adaptability.
Resource Utilization Issues
In a monolithic architecture, all components share the same resources. This can lead to inefficiencies, especially if certain components require more resources than others. Microservices, on the other hand, allow for more granular resource allocation.
Microservices enable economical resource usage as resources can be allocated based on the specific needs of each service. This can result in cost savings compared to a monolithic architecture where all components share the same resources.
The above is true for big scales where a single service/computer is not enough to handle traffic. Otherwise – Micro Services may actually take more resources.
Difficulties in Scaling Teams
As a monolithic application grows, coordinating development efforts among larger teams can become challenging. Different teams might need to work on the same codebase, leading to potential conflicts and coordination issues.
Microservices support smaller, more focused teams, fostering better collaboration and communication. Teams can be organized around specific business capabilities, making it easier to understand and manage the responsibilities of each team.
I’ve written before a List of Features that are good for Micro Services. In general – a startup should focus – fast – to the competitive advantage of the start-up – the unique value proposition that fits the product into the market. Most features – like for example – authentication – are just required to get there