3-Stage Software Development Lifecycle

1. As an industry, our broad goals are to produce the highest quality software possible in the shortest amount of time. For the past two decades, most organizations have used a five-stage software development lifecycle (SDLC) to give teams a way to ensure high quality and detect as many issues as possible before production.?
2. On the other hand, most people see those goals as being in conflict with each other. If you want to create extremely reliable, high quality software, it is going to be relatively slow; if you want to prioritize speed, you will inevitably have more change failures and resulting outages.?
3. The way we’ve managed these competing pressures over the past two decades has been with a development lifecycle that went from development to testing to integration to staging to production. Between the development phase and the “real-world use” phase, there are three environments dedicated to catching issues that would cause the software to work differently in production.?

Two Critical Phases :Development and Production?

• The truth is the most important phases in the lifecycle are development and production. Development is where the application comes to life; production is where it actually lives. The software development lifecycle needs to focus on those two stages, the beginning and the end, and help applications move as quickly and efficiently as possible from one to the othr. A five-Stage software development lifecycle over-Emphasizes the testing, integration and staging portions of an application’s life. Just as importantly, compared to more modern, cloud native approaches, this type of lifecycle is slower and more error-prone — exactly what we want to avoid.?

Rethinking the Phases

Ideally, we’d be able to get all software completely production-ready before leaving the local developer’s machine. In reality, it makes sense to have an intermediate step between development and production to make sure the application has a chance to be evaluated by someone other than the original developer before going into production. But there’s no reason this step should require three separate environments — one intermediate environment should be enough. I think a good name for this environment is “production-like,” making the software development lifecycle?development —> production-like —> production.?

The key to making this work, however, is to ensure that developers are as empowered as possible to test their applications — and that the developer environment and the intermediate environment are both as similar to production environments as possible. The goal is to make sure developers are able to test for as many sources of problems as possible so that the production-like stage is devoted to handling tests that can’t practically be done by developers, such as involving production data, ensuring configurations are correct and testing load.?

What Happens in the Production-Like Environment?

Once we’re in the production-like stage, that’s the time to make sure all environmental factors and configurations have been verified and everything integrates appropriately with dependencies.?

In an ideal world, the service should be treated as a first-class citizen in the production-like environment. This isn’t how most continuous integration works currently. By the production-like phase, the focus needs to be on how requests are moving between services and how interactions are managed, not just whether or not the code is solid.?

Conclusion

Reducing the distance between development and production is a way to simultaneously improve development velocity and reduce change failure rates. Moving to a three-stage software development lifecycle does just that. It also has the added benefit of giving developers more control over the testing and hardening of their services, giving them more confidence to ship.?

Ref:https://thenewstack.io/