Agile and Waterfall Software Development Methodologies
Agile and Waterfall Software Development Methodologies
Considering switching from Waterfall to Agile? Read on to see a comparison of the two methodologies, and which one would work best for you.
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Today, there is an ever-growing list of development methodologies that are used to develop software. Two of the most utilized methods by software developers are Agile and Waterfall.
With the passage of time, the Waterfall software development methodology is losing its worth and slowly becoming obsolete. Many software companies are now turning to the Agile methodology because of its effectiveness and efficiency in developing quality products. Waterfall has a sequential model, which most companies only use when they are clear about each step in the process, while the Agile development has a linear model. The companies who are not sure of each project requirement throughout the process use this methodology for its flexibility.
Below, we will review each of these two methodologies in detail to reveal the positives and negatives of each method for development.
Waterfall Software Development Methodology
Waterfall is based on a sequential development model and is named so because the design steps have to be done in a waterfall-like style. It is a plan in which there are eight different stages which companies need to follow:
The developers visit each step one-by-one and cannot move directly to any random one stage in the process. Once the first step is finished, the developer can only move to the second one and if there is a mistake in the previous step, then the developer cannot move back to fix it. If he does so, then the whole project will have to be scratched and the developer will then have to start over from the first step. There is no room for error at any stage in this model, putting lots of pressure on developers.
Due to this inability to move backward or to skip ahead in the process, each step has to be clearly planned. It is far too expensive to move to the previous step to make any sort of changes, which means that before any type of coding is started, all the required information is gathered and the design process is completed.
Waterfall Methodology Advantages
The client has all of the information about the cost, size, and timeline of the project upfront. They and the development team also have an exact idea about the end result of the program and work toward it from the beginning.
The Waterfall method focuses on scrupulous record keeping, which helps in making the program better going forward.
The well-built documentation of Waterfall enables minimal project impact.
Disadvantages of the Waterfall Methodology
The developer can only go to the next step when they are done the previous one and cannot skip ahead at any time in the process.
The developer cannot go back to the previous step to make any sort of adjustments.
The requirements and needs must be known completely before implementing the Waterfall method.
If the initial requirements are faulty, then the project is essentially doomed from the start.
If there is a requirement error, then the project will have to begin from the start and all of the coding has to be re-done.
If there is any change required in the previous step, then the project will have to start all the way from the beginning.
The project is tested only at the end, so any bugs will be found after all the initial coding is complete.
If an error is written early but is found late, then it will affect the coding of the rest of the project.
The model does not involve the client’s needs completely and can lead to a finished product that may not be 100% satisfactory.
If the client needs changes or wants to add more features, then they will have to wait for the entire process to be re-started, costing time and money.
Agile Software Development Methodology
Due to the disadvantages of Waterfall, the Agile model was developed to be a more efficient way to manage software development. The result is basically a solution to all the problems in the Waterfall method, with its linear design model.
The developers simply start with the base design of the project. After the design is completed, they move to the small modules to begin development. Broken down into monthly or even weekly Sprints, the work on the small modules is completed in sections. The sprints are used to find out the bugs and errors while coding and the developers use the client feedback before moving on to the next Sprint.
There is lots of cooperation needed in this methodology, as the planners, developers, designers, and testers work together on the different iterations of the product. This method is more flexible, as the developer is allowed to make changes at any step in the process and the client’s request can be met easily with the help of this model. The quality of the product is retained whenever changes are made, resulting in a better end product.
Advantages of the Agile Methodology
After the initial planning and preparation, this method allows changes during the process.
Re-writing of the program can be done several times, according to the needs of the client.
It is very easy to add different features to the project because this methodology allows for constant changes. The developers keep the project up to date according to the latest advancements in technology.
Project priorities are calculated at the end of every Sprint. Due to this, the changes are made according to the feedback of the client.
The results of each Sprint are tested so that bugs and errors can be detected and caught immediately. This means that at the end of the project, there minimal errors and bugs found.
Disadvantages of Agile Methodology
The project manager must be extremely organized or else the project can easily get off track, the product can be delivered late, and it will cost more than the original budget. The project manager must be an expert that can manage the workflow properly.
The initial project is not designed according to a definite plan. This means that the final project may seem different from the initial project design, which can lead to confusion on the client's end.
The Agile and Waterfall methodologies each have their unique pros and cons, depending on the development needs and workflow style. Before implementing either of these methodologies, you should know the context of the project. If you have all the information about your project up-front, then the Waterfall method can be a streamlined way to develop software. However, If you do not have a definitive plan for your project and require flexibility, opting for the Agile methodology is recommended.
Published at DZone with permission of Maria Okhrymchuk . See the original article here.
Opinions expressed by DZone contributors are their own.