Continuous Testing and Continuous Deployment Drive a Left-Aligned Process
In software development, the term "shift left" refers to the practice of placing quality at the top of the priority list, from day one. The idea is to eliminate potential surprises or problems that can arise without the appropriate testing at the end of the development cycle or even in the early stages of production.
Quality is elevated simply by working on problem prevention early on during development, which includes testing early, as well. It was originally established to streamline the feedback loop that travels from idea to customer and back again continuously during development. Traditionally, this process would take quite a long time, and if it turned out that the customer didn't like certain elements of an order, you wouldn't find out until they had the opportunity to review the latest version of a project. By then, you're forced to scrap most of your work and return to the drawing board, resulting in the loss of hundreds of labor hours and plenty of resources, including operating funds.
It makes a lot of sense to adopt a left-aligned process when you consider the fact that the average cost of a critical application failure is $500,000 to 1 million per hour. Decreasing the potential for failure is crucial during the development cycle.
How 'shifting left' is achieved
To 'shift left' is to effectively follow two major DevOps practices: continuous testing and continuous deployment. You'll notice that both involve streamlined processes that work to eliminate downtime and keep a project moving forward.
Continuous testing calls for the deployment of automatic tests all along the development cycle, starting as early as possible, and happening as often as possible. This includes deploying a service virtualization or similar environment, which is designed to mimic unavailable systems.
Continuous deployment, on the other hand, involves automating the deployment of new builds and updates, which allows continuous testing to take place.
You cannot have one without the other, simply because they act as lubricants for the working gears, so to speak. In order to continue testing during the length of a development project, you must have deployment rolling out automatically and regularly.
Looking at this, it's easy to think that the entire idea of shifting left begins and ends with development but that's not necessarily true. Some 56% of software defects emerge during the requirement phase, 27% during the design phase, and only 7% during development.
Sometimes, failures that occur during production are never seen or heard of earlier in the life cycle. There are many reasons for this, sometimes failures occur during production because of deployment procedures, but that doesn't change the fact that they can often be remedied earlier on in the development cycle.
A report from IBM System Institute further reveals that defects identified and fixed during requirement and design phases are nearly 100 times less expensive than when they're discovered later. What this tells us is that it's best to find defects and remedy those issues as early as possible, which is what frequent testing helps achieve.
So, to truly shift operations left, development, production, and deployment teams must all work side by side throughout the entire process.
Common strategies for shifting left
While the deployment and function are largely the same, there are a few different strategies that adhere to the 'shift left' concept:
Static testing: Static testing is a series of testing, usually carried out during the early phases of a project, that covers the requirement and design stages. The goal is to find and identify defects as early as possible, that would otherwise be costly if discovered later on. Once the defects are logged, a solution or a way to fix them is added to the pipeline before moving on.
Demand planning: Integral to the idea of 'shifting left' is the rule that endpoint demands must be met early on in development so as to mitigate future problems. This enables proper planning and building a strategy to adhere to budget constraints, resources, and test plans. Often, development teams and test analysts work directly with operational stakeholders to find a clear path of execution.
Risk-based analysis: Risk-based analysis is a method of identifying and discovering the likelihood of failure for each test scenario or activity. It has a waterfall effect where the analyst or designer continues to discuss risks with all parties along a development cycle.
Unified test strategy: Unified test strategy is often a high-level or end-to-end solution that concerns everyone with a certain aspect of development. Quality control, for example, is a critical element to consider along all stages of a project and by nearly every party involved. Ultimately, the idea is to ensure that each respective team has the opportunity to fulfill their duties for a joint or collaborative project.
What will shifting left help you achieve
It depends on the execution and success of the project in question, of course, but there are many benefits awarded to teams that shift left early. For starters, more of the development process can be automated in a more efficient manner. This is because there's a general reduction in human error and issues are identified and resolved much faster and earlier.
This results in quicker delivery of the product in question as well as improved satisfaction of the customers. Furthermore, it ensures that the product delivered is truly bug and glitch-free, because many of the problems that would have appeared later have already been solved. That's the beauty of testing early and testing often; you can ensure that you're delivering a fully-functional product in the end.
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