====== The next best thing in software architecture to try out======
by Egor Zemlyanoy
===== Introduction =====


In the permanently evolving field of software architecture, staying updated with the latest trends and techniques is crucial for both individuals to be up-to-date with modern trends and new concepts and companies to provide the best possible software. This essay aims to explore potential software architecture patterns and conclude one of them to be the most interesting one to try in future projects.

To begin with, let me guide you through several most popular software architecture design patterns such as MVC (model-view-controller), Layered architecture, Repository architecture [1].

===== MVC =====


MVC, or Model-View-Controller, is a software design pattern widely used for organizing code in a modular and maintainable way. Each part of this pattern has a separate meaning:
  - Model: Represents the data and business logic of the application. It responds to requests for information, retrieves and stores data, and notifies observers of any state changes.
  - View: Displays the data to the user and handles user input. It is responsible for presenting information and forwarding user input to the controller.
  - Controller: Receives user input and initiates actions to update the model or view. It acts as an intermediary between the model and view, handling the flow of data and updating the user interface accordingly.
Architecture built upon such pattern has several advantages as well as disadvantages.
Advantages:
  * Separation of Concerns: MVC separates the application into distinct components, making it easier to manage and maintain.
  * Modularity: Each component can be developed and modified independently, promoting code reuse.
  * Testability: Components can be tested independently, facilitating unit testing for each part of the application.
  * Scalability: MVC supports the scalability of an application by allowing for the addition or modification of components without affecting others.
Disadvantages:
  * Complexity: Implementing MVC can introduce complexity, especially for smaller projects where the additional structure may be unnecessary.
  * Learning Curve: Developers might require time to understand and adapt to the MVC pattern.
  * Tight Coupling: In some cases, the components can become tightly coupled, making it challenging to change one part without affecting others.
There are several types of systems suitable for MVC pattern such as: web applications where MVC is commonly used due to its separation of concerns and modularity; desktop GUI-based applications, such as those built with Java Swing or .NET Windows Forms, which can also benefit from MVC.

===== Layered architecture =====


Layered architecture is a software design pattern that organizes an application into a set of horizontal layers, where each layer has a specific responsibility and interacts with adjacent layers. Here are commonly used layers:

  - Presentation Layer (UI): The topmost layer responsible for presenting information to users and receiving their input. It communicates with the underlying layers to retrieve and display data.
  - Application Layer (Business Logic): Contains the application's business logic, handling tasks such as processing data, applying business rules, and coordinating communication between different layers.
  - Domain Layer (Business Entities): Represents the core business entities and rules. It encapsulates the business logic and ensures data consistency and integrity.
  - Infrastructure Layer (Data Access, External Services): Deals with data access, storage, and interaction with external services. It provides a way for the upper layers to persist data and communicate with external components.
Architecture built upon such pattern has several advantages as well as disadvantages.
Advantages:
  * Modularity: Layered architecture promotes modularity, making it easier to manage and maintain each layer independently.
  * Scalability: Individual layers can be scaled independently, allowing for more efficient resource allocation.
  * Reusability: Components within each layer can be reused across the application or in different projects.
  * Maintainability: The separation of concerns simplifies maintenance, as changes in one layer are less likely to impact others.
Disadvantages:
  * Rigidity: The strict separation between layers may lead to increased coupling, making it challenging to modify one layer without affecting others.
  * Performance Overhead: The communication between layers can introduce some performance overhead, especially in cases where real-time interaction is crucial.
  * Complexity: In large applications, the number of layers can introduce complexity, potentially making it harder to understand and navigate the codebase.
There are several types of systems suitable for Layered architecture such as: Enterprise Applications mainly because modularity and maintainability for such systems are crucial; Web Applications, especially those built using MVC frameworks, follow a layered architecture for separating concerns related to the user interface, business logic, and data access, as well as Business Process Management Systems cause clear organization provided by a layered architecture  becomes handy for handling complex business processes.

===== Repository architecture =====


Repository Pattern is a design pattern that provides an abstraction layer for data access in software applications. It can be divided into several parts:
  - Repository Interface: Defines the contract for data access operations, such as querying, saving, and deleting entities.
  - Repository Implementation: Implements the repository interface and is responsible for interacting with the data storage (database, file system, API, etc.).
  - Entities: Represent the application's data model and are typically mapped to the underlying data storage.
Architecture built upon such pattern has several advantages as well as disadvantages.
Advantages:
  * Abstraction of Data Access: The pattern abstracts the details of how data is accessed, providing a clear separation between the application's business logic and data access code.
  * Testability: Repositories can be easily mocked or replaced with test implementations, simplifying unit testing of the application.
  * Centralized Data Access Logic: The repository consolidates data access logic in one place, making it easier to manage and maintain.
Disadvantages:
  * Complexity: For smaller projects, the Repository Pattern might introduce unnecessary complexity.
  * Overhead: In some cases, the additional layer of abstraction can introduce a slight performance overhead.
There are several types of systems suitable for Repository Pattern: Data-Driven Applications which heavily rely on data access, such as CRUD (Create, Read, Update, Delete) operations, may benefit from the abstraction provided by the Repository Pattern; Large Scale Applications with extensive data access requirements, where a clear separation between business logic and data access logic is essential for maintainability;

===== Summary =====

All these patterns are pretty well-known and have established in the current software development. The next best thing for me to try out is a Repository architecture pattern because recently I started working in a huge data-driven company which doesn’t even have separate software developed. The company uses some common ETL/ELT tools for manipulating the data and BI instruments for accessing the data. In my opinion developing a software built upon Repository architecture pattern may become essential for us to stay up-to-date with the current market.

===== References =====

[1] Software Engineering, 10th edition by Ian Sommerville, 2016