A more classical explanation of how to upgrade Monolithic Code to Modular Code

A description of what the world used to look like, before modelcode.ai

Changing monolithic code into modular code is a core aspect of ensuring the codebase is maintainable and easier to understand and test. The process typically involves the steps detailed below.

1. Identify responsibilities: Begin by identifying the different functionalities or responsibilities that the monolithic code performs. This can involve identifying each distinct task that is completed within the system, regardless of the current organization of the codebase.

2. Design modules: Once functionalities are identified, design the architecture of the different modules that will be created. Each module should encompass a single functionality, ensuring separation of concerns. Also, determine how the modules will interact with each other and any APIs they will expose.

3. Breakdown monolithic code: Start decomposing the monolithic code into the different modules. It is usually best to start breaking down the code into bigger chunks and then further divide as necessary, ensuring that the code in each module is highly cohesive and loosely coupled.

4. Reformat code: As you move the code into modules, reformat it into the appropriate structures needed for each module. This usually involves adopting the necessary syntax or conventions within the programming language used to define modules.

5. Update dependencies: Change any code that depended on the monolithic structure to depend on the newly formed modules. This can include updating import statements, changing how functions and methods are called, and updating tests.

6. Repeat process: Since you are dealing with a monolithic codebase, it is expected that the size would be large. Therefore, it might be impractical or risky to try to do everything in one go. Therefore, perform these steps on small sections of the monolithic code base at a time and gradually transform the entire system.

7. Test: After each module is created, ensure that they pass all tests and that inter-module interaction isn't causing any unforeseen issues.

The process involves refactoring, testing, and possibly redesigning the system's architecture. It is a complex task that requires a deep understanding of the system and careful planning, but the resulting modular code can offer benefits in terms of maintainability, scalability, and testability.