TDD as the way to reliable software

As a dedicated development team specializing in both frontend and backend, we really appreciate the power of test-driven development. This approach serves as a tool that enables us to build robust applications and systems. So, let's dig into what this approach is all about!

Test-driven development involves a set of practices where tests mirroring software requirements are written before the functional code.

It may seem highly technical, all about how developers code, right? Not quite.

Test-driven development really impacts how well a business can adapt and how loyal customers are. It speeds up adding new features that customers want and makes the software more reliable. And that's a big deal for businesses!

At first, it might seem like extra work for developers. So, why does Test-Driven Development (TDD) actually speed up feature development? Well, when developers write code, they naturally need to test it to ensure it works correctly. This usually involves multiple tests. Once a test confirming a feature is written, it's quicker to automate its testing and launch, rather than manually retesting it every time.

Developers often need to refactor their code to make it more extendable and flexible, especially for rapidly growing applications. Without a quick validation method, they become hesitant to modify their existing code. This can lead to a fragile structure that's hard to change.

In simpler terms, a system without tests usually can't develop quickly and is vulnerable to being outpaced by competitors.

Let's talk about reliability. Developers are human, and mistakes can happen. Writing tests based on all requirements serves as a double-check, ensuring they understood what needs to be done. This approach also adds a second layer of validation, confirming that everything functions as intended.

But it's not a magic solution. There are a few downsides to keep in mind.

1. Tests that are written incorrectly can turn into a "test hell," where creating a new feature requires rewriting many tests, slowing down the development process.
2. In complex systems, it's easy to write tests that fail without an actual issue. To prevent this, developers should thoughtfully design their tests.
   
3. In a large codebase, tests can become slow, which can hinder developers as well.
   

In upcoming blog posts, we'll explore a few practices that can help address these challenges.

TDD also aligns well with Agile practices. We personally use both approaches to meet our customers' needs.