Behavior Driven Development (BDD) extends and enhances Agile and other software development methods. Here is an overview of BDD: what it is, how it works, and why it’s a strong practice for software development.

The Benefits of BDD

BDD recognizes one of the biggest challenges inherent in software development. The people who understand the functionality and end user expectations, Business Analysts, do not necessarily understand how applications are technically built or tested. This can result in code that “works” and passes tests but ultimately creates unintended functionality or a complete miss all together. As a result, new products and feature releases are stalled, and customer experience is impacted (this sentence is about business impact but there are others for sure).

What is BDD?

A report from CollabNet VersionOne, which has been following the Agile landscape for more than a decade, shows that 97 percent of organizations claim they now practice Agile development methods. While this demonstrates that the concept of Agile has become the “new normal,” we have found that genuine adoption of the Agile “mindset” and realization of the full benefit to be gained from Agile continues to fall far short of achieving universal transformation.

Behavior Driven Development represents a fundamental paradigm shift, born of an Agile mindset, that can make Agile aspirations into an operational reality.

Behavior Driven Development is a fully-collaborative development and Shift-Left test automation process derived from the Test Driven Development Method (TDD). When executed properly, it enforces Agile (and other) software development practices by finally operationalizing Agile principles of direct collaboration and communications between all stakeholders.

At its core, BDD promotes stronger communication, clearer requirements, increased test automation and ultimately a higher quality product. While the Agile methodology focuses on people doing the development work and how they work together, the TDD paradigm puts forth the idea that the best way to know if code works properly is to decide in advance how you know it will work—before you begin building it. In other words, what is the test that will be used to ensure it works the way the developer intended it to work?

How BDD Works

BDD extends the test-driven paradigm by enabling and empowering tighter alignment across projects teams and stakeholders—bringing the business and the end user experience perspective into the process. The foundation of this collaboration is called Specification by Example, a process of requirements elicitation by which teams build software through the definition of functionality scenarios. This approach is a powerful enabler for stakeholders and creates clearer input and end-user context into the definition of each feature.

In turn, the development is more efficient and only the code needed to support the feature is produced.

Finally, test automation development can begin immediately before a single line of application code is written. Less toil means more speed to market! Quality measures also improve as developers build with a clearer conceptual understanding of how end users will use functionality.

Specifications written in plain language are married to tests to prove functionality. This is where the BDD method proves its value: as developers code, testers build automated tests per Specifications. As code is completed, testing occurs automatically.

BDD Tools

While there are multiple tools to support teams using BDD, three are particularly helpful. Gherkin, which is a business-readable language tool, offers a framework for defining requirements and integrating underlying test automation using the Specification by Example process. Two similar development frameworks (Cucumber for Java applications and SpecFlow for BDD frameworks based on a .NET platform) implement BDD by creating a thin structural layer on top of traditional automated tests, allowing teams to write tests and reports that anyone can understand, regardless of their technical knowledge. It can integrate with other test tools such as Selenium and reduces test execution time 40 to 80 percent when compared to manual testing.


Interested in taking the next step with BDD? Reach out to us here; we will provide some insight on how the BDD approach can strengthen your software development lifecycle