Architectural Methodologies for Front-End Development: Types, Advantages, Disadvantages

Imagine a situation: you've inherited code with no structure, no understanding of where or how to find specific parts of the code, or where to make changes. The "worn-out" components folder resembles a list of words from a dictionary, but without any definition of what each component means.

No, this isn't an old project; it just recently went into production. You received a task from the client: improve and enrich the application with new features. You open it, and there are files scattered chaotically across different directories, and duplicate code that should have been removed "yesterday." You start thinking about how to bring order here, you google... And then you come across descriptions of various methodologies that can partially or completely solve your problems. So what to choose?

Before considering several popular methodologies, let's understand why architecture is needed, what advantages and disadvantages it has. This will make it easier to choose what suits your project.

Advantages of Architectural Methodologies

Simplicity in use, extension, and code maintenance

With the use of one approach or another, it becomes possible to organize the entire application into separate independent parts. The developer does not have to worry about whether subsequent changes in the code will affect the operation of other parts of the system.

Adding new functionality will also be simpler, as the entire team will equally understand where and how to make changes. Developers will adhere to architectural decisions and rules. Everyone will work with a logically separated part of the project, defined according to the chosen architecture. For example, a module, component, or file.

Code reusability

Separating functionality using a specific structure and rules allows for easy reuse in separate parts of the application or even outside the project.

A good example, which can often be found, is a complex table with a set of different properties and configurations, which has many styles, its own separate variables, interfaces, or even functions for working with external APIs. Such separation significantly affects the speed of development, as a certain block of functionality can be used several times.

Availability for new team members

You can indicate which approach you have applied, which is the standard. A new team member may already be familiar with the logic, or they can explore it by reading online sources or referring to project documentation.

Facilitating code testing

With a clear architecture, it becomes possible to test each module separately, which makes testing controlled and reduces the risk of errors.

Code scalability

Independent parts of the program are easier to change and extend without the need to make changes to the entire code. All team members can simultaneously be involved in working on a specific part of the application, having minimal dependence on each other.

Disadvantages of Architectural Methodologies

Additional time costs

Creating abstractions, additional code for setting up communication between different parts of the system, starting the project, and maintaining all the conditions of the chosen architecture – all this requires a lot of additional hours.

Difficult for beginners

It will likely be more difficult for a Junior developer to get into the project, as some rules, conditions, and limitations may be unclear and non-obvious to them.

It is more difficult for juniors to understand complex concepts. Accordingly, they need more time for adaptation and onboarding into the project. We do not exclude possible errors at the beginning of work.

To achieve these advantages, developers constantly improved the structure of their projects. Later it became clear that the team's developments from one project could be used in another or shared with colleagues from another project. This is how independent architectural methodologies began to appear, gradually gaining popularity and winning new adherents among developers.

Having analyzed the advantages and disadvantages of using architectural approaches, I propose to move on to examples.

Types of Architectural Methodologies

Modular Architecture

One of the most common methodologies, simple to use. In such an architecture, the application is divided into different levels, where each has its role and responsibility. Here's what it looks like:

Let's consider each element separately.

Pages: The page level is responsible for displaying modules, without containing business logic. For example, the application login page will involve displaying modules such as the "header," application footer, and login form.

Modules: This is the core logic of the application. Modules handle errors, work with APIs, are responsible for business logic, store their own state, and have their constants or utilities that the component uses.

They have a certain structure that implements the concept of a public API using an index file, which in turn exports only those parts of the module that you make available. This implements the principle of encapsulation, if we draw an analogy with OOP.

Examples here could be an application login form or a list of products. Modules work independently of each other and do not interact directly with other modules.

Components: These are elements that can contain certain logic, but unlike modules, they do not implement specific functionality. For example, a product card component can handle events or display data passed to it.

UI (Interface Components): The UI level includes basic interface elements: buttons, input fields, tooltips, etc. These are small components that are used as building blocks in other parts of the program.

You can also create global directories to store such common resources as hooks, utilities, or constants that can be used throughout the application. But note: modules do not use other modules. This principle supports isolation and avoids unnecessary dependencies between modules.

Advantages of modular architecture:

• Module isolation using public APIs: each module has its own index file, which exports only those functions and components that are necessary externally. This reduces the risk of unintentional interference with the logic of other modules.

• Module reusability: thanks to a clearly defined structure, modules are suitable for reuse in separate parts of the application or in different projects.

• Ease of module removal: thanks to isolation, a separate module can be removed or replaced without significant changes throughout the application.

• Flexibility of using feature flags: modules are simply enabled or disabled using feature flags, which simplifies the deployment of new features.

As for the disadvantages, we have the following:

• Modules cannot directly use other modules. This limitation causes difficulties when modules need to exchange data or establish dependencies between them.

• Difficulty in determining where to place code: developers may face a dilemma: should certain functionality belong to a module, or would it be better for it to remain a separate component?

• Global variables and state: although this type of architecture is focused on isolation, there may still be global constants or state (for example, a common global store) that are used throughout the program.

Modular architecture can be applied in projects of any complexity and in teams of various sizes.

There is another approach, more complex compared to modular, but with its own documentation and even a community. The architecture that we will consider next is suitable for both medium and large teams and projects.

Atomic Design

A methodology developed for creating structured and scalable interfaces. It is based on the idea that the interface can be divided into five levels of abstraction that correspond to natural structural elements of design. This approach helps organize components into a clear and reusable structure.

Atomic Design promotes clarity, consistency, and scalability of the interface. This principle is followed in design when creating mockups for web applications.

This approach is also used to create component libraries that will be used in different projects. In general, the methodology is similar to the modular approach discussed above, simple and clear.

The structure of levels in Atomic Design architecture is as follows:

Atoms: The basic, smallest units of the interface that cannot be further divided. They do not contain complex logic or interactions and are used to create larger components. Atoms are the basic components of the interface. For example, a button or an input field.

Molecules: Combinations of atoms that work together as a single functional block. These are mid-level components that can contain simple logic. They should encapsulate and perform a simple task. For example, an input field with a text label for it.

Organisms: More complex components consisting of molecules and atoms, forming functional blocks of the interface. At this level, business logic is usually present. Organisms are usually responsible for a significant part of the UI. For example, navigation panels, tables, or cards.

Templates: The template level is responsible for arranging organisms on the page. They define the structure of the interface without specific data content. That is, in essence, templates are a prototype of the future page of your application. It is here that the positioning of the functional blocks of the page is determined. For example, the header, footer, or sidebar with navigation.

Pages: This level fills templates with specific content. Pages display the final appearance of the interface with all the data and styles that will be displayed to the user.

For storing common resources, configurations, constants, you can create additional directories at a higher level.

Atomic Design architecture has the following advantages:

• Easy to navigate the code: a clear structure facilitates understanding the code and navigating the project.

• Flexibility: it is easy to add, delete, or replace individual parts of the application.

• Easy maintenance: changes in basic components are automatically reflected throughout the interface.

• Scalability: promotes the scalability of both the application and the development team.

Among the disadvantages:

• UI-oriented: the methodology focuses more on the interface, not on business logic.

• Additional time costs: the approach requires additional costs for creating abstractions in your application, such as templates.

The methodologies mentioned in the article and other examples that you can find online may at first glance seem complex to those who have not previously encountered similar solutions for organizing architecture in a project. However, mastering these approaches will undoubtedly be useful to you and help in routine tasks. And every developer definitely faces them: this includes forming the project structure, and correctly positioning and reusing code.

Both architectures considered are very common and can often be found in projects. They are easy to use, with many clear examples and adaptations to the needs of a specific project. So, starting work on a new project or finding time to refactor an existing one, take care of the future of your code – create the right architecture for it.