Shift-Left Testing: What It Is and How It Works

If your development team isn’t yet using shift-left testing, you could be wasting time, money, and energy. Teams that practice shift-left testing are able to identify potential roadblocks early in the process, change scope when needed, and improve design to avoid buggy code. When a bug does occur, it can be identified and dealt with quickly so as not to impact the project later on. 

Shift-left testing proposes to help agile teams become more agile. Here’s what shift-left testing is, how it works, and how to think about shift-left security. 

What is shift left testing?

Shift-left testing is all about beginning QA testing at an earlier stage of the development process. The goal of testing early and often is to reduce the number of bugs that occur as early as possible. 

The “shift left” meaning comes from the sequence of stages in the development process. Consider the traditional software development lifecycle. It happens in six stages, specifically: 

(image source)

1. Requirement analysis
2. Feasibility study
3. Architectural design
4. Software development
5. Testing
6. Deployment

The shift left meaning comes from the idea that you’re literally shifting the testing stage to the left, where it will fall earlier in the software development lifecycle timeline. A shift left strategy does not mean simply shifting testing to an earlier stage — in that sense, the term is something of a misnomer. In reality, a shift left strategy involves an iterative approach in which testing occurs at every stage of the development process. 

“Shift Left doesn't mean ‘shifting’ the position of a task within a process flow. It also doesn't imply that no testing is done just before a release. It should be seen as "spreading" the task and its concerns to all stages of the process flow. It's about continuous involvement and feedback,” wrote Devopedia. 

There are many benefits to the shift-left approach. Because developers can detect bugs early and often, they can reduce the time it takes to release software and save on production costs. NIST estimates that resolving defects in production can cost 30 times more; that number climbs to up to 60 times more in instances of security defects. Likewise, the end code is higher quality — it contains fewer patches and fixes, delivering a product that is stable and developed on time and on budget. 

Shift left methodology

There are a few easy steps to introducing a shift left methodology to your organization. 

First, create a team of developers who are tasked with QA testing. Brief this team on your code standards to get everyone on the same page and to avoid bad or insecure code. Testers must also understand what the code is being used for and the outcome the development team (and end user) hopes to achieve. 

“Shift Left Test in Agile works best when QAs come in from the first brainstorming session. When developers throw around ideas on how to build a website or app, QAs must be present. This helps them understand the fundamental concepts, allowing them to design better tests for the Continuous Testing stage,” wrote the experts at BrowserStack.

Map out where throughout your development process you can include testing. Organizations that use the Agile methodology, for instance, may include testing at the end of every spring. Others may use unit tests for every new feature that gets developed. The key to shift-left testing is doing it early and often. 

Finally, make sure testing is informing future development both within the existing project and for new projects going forward. Set up a feedback loop to capture common bugs and errors and to identify ways to automate the testing process. Continuous feedback helps everyone involved and improves coding standards in the long run. 

Shift left security 

How does the shift-left approach relate to security? Shift-left testing is just one manifestation of the overall shift-left approach. Shift-left security applies the same principles, directing devs to test throughout their daily work. 

”This means integrating security testing and controls into the daily work of development, QA, and operations. Ideally, much of this work can be automated and put into your deployment pipeline. By automating these activities, you can generate evidence on-demand to demonstrate that your controls are operating effectively; this information is useful to auditors, assessors, and anyone else working in the value stream,” wrote the experts at Google Cloud. 

How can you begin to implement shift-left security? Here are a few places to start.

• Include a security expert early in the software design process.
• Implement best practices like discouraging hard coding of credentials, API keys, and other secrets within code and remediating these violations whenever they occur.
• Use InfoSec approved tools that ensure your code and your environments don’t unnecessarily increase your organization’s security risk. For example, Nightfall provides a native GitHub integration that scans push events for API keys, credentials, and PII in order to remove them from your GitHub Organization. Nightfall also provides other tools, like a GitHub Action and a CircleCI Orb that can be used at different parts of the software development lifecycle to prevent the issue of secrets proliferation within your code.
• Create review phases for security in different parts of the development process. 
• Keep pre-approved code in user-friendly libraries, packages, and toolchains.

To get started with Nightfall, schedule a demo at the link below.