Software Methodologies — Waterfall vs Agile vs DevOps

The IT industry is ever-changing. In the past decade, it went through continuous evolution of technologies and methodologies. There is a  constant need to upgrade to integrate different solutions and meet the needs of market demands. 

Starting from the waterfall approach, the industry has shifted towards agile methodology and now focuses massively on DevOps principles and best practices. Have you ever wondered why billion-dollar companies like Amazon, Netflix, Etsy, NASA, Walmart, Nordstrom, etc., have adopted DevOps? Where did it all start from? What caused DevOps to be developed? Let’s try to answer all these questions in this brief comparison of methodologies. 

What Is the Waterfall Model?

This model is a first-of-its-kind software development technique that adheres to the linear software development process. The waterfall model requires that each step be finished before moving on to the next. Each phase in sequential software development is separate and needs to be extremely clear from the start. Gathering requirements is the first of the steps, which is then followed by analysis, design, coding, testing, and deployment.

With the advent of the dynamic nature of the software development process, where there needs to be constant change in implementation, the model progressively became out of date due to its rigid nature of development, as one cannot go back to the previous phase to make any changes. The waterfall approach is best suited for - 

Drawbacks of the Waterfall Model

• The effectiveness of obtaining and recording requirements in a way that is meaningful to a client in the area where the waterfall model consistently falls short. Details and specifics supplied early in the process often terrify clients. 

• It's possible that a customer will be unhappy with the delivered software product. Still, they typically won't notice until the project is almost finished, and making the necessary changes can be quite expensive.

What Is Agile?

Agile is a team-based, iterative development methodology. This strategy places a strong emphasis on an application's quick delivery.  

Deliverables are prioritized in order of business value and as chosen by the client. If all scheduled work for a sprint cannot be completed, the sprints are reprioritized, and the information for future sprint value is decided.

Agile depends heavily on the developer, tester, and customer involvement at all stages of the project, but notably during reviews.

Following are the various process used to implement agile :

• Scrum - it's a 7-9 members team-driven development environment. A scrum usually consists of a scrum master, product owner, and scrum team. 
• Crystal methodologies - This methodology emphasizes the interaction between people more than tools. 
• Dynamic software development method - Also known as the “rapid action development model,” where team members are empowered with decision-making capabilities. 
• Feature-driven development (FDD) - In this methodology, each phase involves completing a small feature within the given time.

Advantages of Agile 

• The client can be involved in all stages of the development process and can even contribute.

• By collaborating actively and directly with the project team throughout, the customer develops a strong sense of ownership.

• If the marketing of the application is of the utmost importance, the Agile technique can be used to create a basic version that can be iterated over repeatedly until the app is finished.

What Is DevOps?  

DevOps is an engineering culture that focuses on integrating development and operations together for more efficient development. The term "DevOps" refers to organizational collaboration rather than a framework or standard. To achieve continuous integration and deployment, the various stages of the DevOps life cycle are concentrated on continuously monitoring, operating, implementing, and responding to end-user feedback.

DevOps lifecycle consists of 8 processes that include:

1. Planning: Before working on a project, plan, track, visualize, and summarize it.

2. Coding: Developers use version control platforms like Git, Github, and Gitlab to write their code.

3. Building: Developers use tools like Kubernetes, Docker, Maven, Gradle, and Apache to create a pre-release version that is recognized by a build number rather than a release number.

4. Testing: The QA team runs the new piece of code through testing to find and resolve bugs.

5. Release: In this step, the built process is planned, scheduled, and controlled in a new setting.

6. Deploy: During this stage, the deployment procedure is ongoing. It is done in a way that any modifications made to the code at any point shouldn't have an impact on how a busy website operates.

7. Operate: The product or application is supplied to the customer for usage after it has been deployed, where he can utilize it for his everyday needs.

8. Monitor: The operation team will address any improper system behavior or problems discovered in production during this period.

Advantages of DevOps

• Faster Delivery - DevOps principles are always known for faster iteration and standardized processes that make them readily available in the market
• Breaking down silos - DevOps has replaced the antiquated linear process in which one team would finish all responsibilities related to a project before handing it off to another team to continue working on it, and so on.
• Software quality - Because DevOps facilitates frequent releases, it's easier to discover and fix problems which in turn results in higher software stability. Because of this, there is more time to concentrate on quality and innovations.

Key Differences Between the Three Models

Software development projects that are clearly defined, predictable, and unlikely to undergo considerable change are best handled using the waterfall method. Typically, smaller, simpler undertakings fall under this category. Waterfall projects don't incorporate feedback during the development cycle, is rigid in their process definition, and offer little to no output variability.

Agile methods are built on incremental, iterative development that promptly produces a marketable business product. The product is broken down into smaller pieces throughout incremental development, and each piece is built, tested, and modified. Agile initiatives don't begin with thorough definitions in place. They rely on ongoing feedback to guide their progress.

In Agile development, DevOps is all about merging teams and automation. Agile development is adaptable to both traditional and DevOps cultures. In contrast to a typical dev-QA-ops organization, developers do not throw code over the wall in DevOps. In a DevOps setup, the team is in charge of overseeing the entire procedure.

Final Thoughts

There are plenty of approaches for software development. However, every organization is different, and their chosen methodology largely depends on the company's projects, audience, and various other parameters. This blog briefly overviews the three main types of software methodology.