Iterative development is a process, or a method, in which a software product is developed after breaking it down into smaller, easily developable “chunks” of code. The entire software application or utility is “disassembled” and split up into much smaller “features” portions. Each portion is individually designed and developed. Individually developed software features can be tested and corrected. Development typically occurs in repetitive product development cycles. The cycles should ideally result in fully functional product features. When enough features are developed, they can be integrated to form a bug-free working version of the final product.
What is iterative software development using a particular framework or methodology? In a nutshell, it is can be understood as implementing the iterative software development process in accordance with the unique rules proposed by the particular framework or methodology.
When is an iterative software development model used?
Iterative software development is most commonly used with incremental development – the software production or development cycle is split up into smaller segments, and each segment produces fully developed software features at the end of its run. The iterative cycle is repeated until all the product features are developed. It is a key development method used in Agile frameworks and methodologies.
Typically, iterative software development model is used when a project is large or complicated, and likely to extend for a longer duration. It becomes more difficult to track and monitor the project development parameters – time, resources, productivity, testing, acceptance levels, etc. when traditional software development frameworks such as Waterfall are used, since such development methodologies are not specially designed to tackle issues pertaining to rapid software development and delivering bug free software releases in relatively short times. This is where Agile scores. It splits up the entire project into smaller, easily manageable “chunks” of product features, and each feature is developed, tested, and deployed independently through iterative cycles known as “sprints”. Each sprint is individually designed and planned in a special event known as a “sprint planning meeting”. Time-boxed development leads to increased productivity and increased client satisfaction levels.
Agile incremental development methodology and Waterfall methods
Waterfall development is based on “stages”. Software development occurs through “Waterfall” stages. During each stage, a certain process is carried out and the project is “developed” up to a certain “level”. The entire product is developed when each of the stages is completed in totality. Waterfall stages cannot be “reversed” or backtracked. This can often prove to be risky at times because if there is an inherent flaw in the project design, or bugs have not been identified properly during the “testing” stage, the error cannot be corrected or resolved unless all the stages are repeated once again. This can prove to be expensive, time-consuming, and counterproductive at times.
Agile is based on incremental development methodology. The product is split up into its constituent features. A small group of features is developed in repetitive development cycles known as sprints. At the end of each sprint, shippable product features are submitted for verification purposes to the product owner. The development should be deployable and bug-free. After all the features are developed through sprints, they are integrated to form the complete product.
The main difference between Waterfall and Agile is that development is staged in Waterfall while it is of an iterative nature in Agile. Waterfall cannot be reversed, while Agile keeps on changing constantly to meet the most current development requirements.
Iterative software development at a glance
- Initially, a “top-level” project design is created to “give shape” as to how the project deliverables should be ideally developed. The specifics are not addressed during the project start-up but are “designed” later on. The product owner is largely responsible for designing the project.
- The entire product is developed, tested, and “deployed” in stages. Development is carried out in iterative development cycles known as “sprints”.
- It becomes possible to analyze, remove defects in the development “phase”, and check for regression before its occurrence since a product feature can be individually developed, tested, and “rectified” after it is checked for bugs during the sprint cycle. Technical issues are identified and addressed to “well in advance” and not allowed to “escalate”. User feedback plays a very important part in the Agile process.
- Less time is spent on documentation and more focus is “created” upon developing product features. Productivity takes precedence over documentation.