The secret to building applications that users love? Test, test, and test again.
We cannot overstate how important testing is -which is exactly why you need to know the Software Testing Life Cycle (STLC) inside out if you want your application to impress.
Here's an at-a-glance guide to what the STLC involves, its key phases, and, crucially, how to optimize it for best results.
If you're building an application, whether for your own business or for external clients, it's safe to say you want to guarantee it runs smoothly and safely before you launch.
The Software Testing Life Cycle (STLC) is a systematic testing approach that helps to ensure that your application meets key requirements, is defect free, and (to borrow a phrase from organization queen Marie Kondo) sparks joy for your target user base.
The STLC follows a series of phases with specific objectives. These phases remain the same for every software development project you test, providing a standardized testing approach that helps you guarantee quality with each release.
This offers several benefits for both your project and your wider business goals, including:
The software development life cycle (SDLC - the acronyms are annoyingly similar) consists of six phases:
Whilst your software testing itself will take place across the development and testing phases, you can start the STLC much earlier. You can begin defining your test requirements, deciding on test scope, and building test environments as soon as the requirements and application architecture are in place. This helps the cycle run as effectively as possible, and allows you to identify defects earlier in the process.
If your organization uses Agile software development methodology, you'll be doing the process above for smaller sections of the software, usually in shorter, consecutive 'sprints' - but the principle remains the same.
There are six key phases to the software testing life cycle:
Each STLC phase is designed to meet a specific purpose, and has a defined set of activities and exit criteria that you'll need to complete before moving on.
Entrance criteria
Purpose
During the requirements analysis phase, your team dives into the application's requirements to identify what to test and how to test it. This provides a solid knowledge base for the following phases, in which you plan, design, and execute the tests.
Activities
Testing/QA teams should collaborate with stakeholders to understand requirements in detail and build a prioritized list of testing activities. If there's potential to automate any testing processes it should be discussed here.
As part of your requirements analysis, you should create a Requirements Traceability Matrix to map user requirements against test cases. This will help you track the success of your tests further along in the process.
Exit criteria
Purpose
During the test planning phase, your team gets to grips with the 'how', 'how long' and 'how much' questions that help stakeholders keep on top of timelines and budgets.
Activities
Your team agrees on your testing approach, strategy, and scope, estimates the effort/costs required, and identifies which testing tools to use.
Creating a Test Plan document ensures that all of this information is available to stakeholders from a single source of truth.
Exit criteria
Purpose
During the test case development phase, your team builds and optimizes test cases and test scripts, so that the execution phase is as effective as possible.
Activities
Your team should identify the data they want to test, create test cases, and (if applicable) write all the automation scripts needed. You can then start the development process for test cases for individual units.
Exit criteria
Purpose
During the test environment setup phase, your team identifies the conditions (hardware and software) under which you'll test your application.
Activities
Your team creates the test environment and performs a smoke test - that's a readiness check on the testing environment that ensures it's good to go.
Exit criteria
Purpose
Your team tests the application according to your test plan, using the environments, scripts, and cases created in previous steps. This identifies any defects that need to be corrected before the application is shipped.
Activities
Your team executes and maintains test scripts, documents the test results, and logs any defects the tests identify in the Requirements Traceability Matrix.
Once the developers have addressed these defects, you'll retest the defect fixes and repeat as needed until all defects are closed.
Exit criteria
Purpose
This is your opportunity to evaluate the testing process - what worked well and what didn't work so well - and identify some key takeaways for next time.
Activities
Your team analyzes the effectiveness of the STLC based on time, coverage, cost, and quality - then documents any key learnings and potential process improvements.
It's also a good idea to carry out a test result analysis to identify the defect distribution by type and severity. This is super useful feedback for developers, who can use it to improve their own processes.
Finally, now's the time to put together a test closure report and get it signed off by stakeholders, as an agreement that the testing stage is complete.
Exit criteria
A STLC that runs faster whilst being more effective is the dream, right? Here are a couple of ways you can achieve this
'Shift left' is one of the fastest-growing development trends right now, thanks to its focus on defect prevention over finding and fixing bugs pre-release.
Shift left methodology emphasizes the importance of involving software testing teams in the earliest stages of the development cycle. This allows for early and continuous testing, which allows teams to fix issues early on in the process, when it is cheaper and easier to do so.
Crucially, it also involves testing teams in discussions with key stakeholders earlier, giving them a better handle on key testing requirements, and allowing them to gather feedback to optimize their test plans.
The best way to improve something? Measure it.
Monitoring code quality metrics allows you to take a baseline measurement for code quality, then track the success of actions designed to improve it. Higher quality code \= fewer defects \= less time needed to fix those defects.
The best metrics to use will depend on your team's preferences, requirements, and workflows, but the following are a great place to start:
Read our full guide to testing automation metrics here
Automated testing isn't new. Over the past decade, options for automating parts of the software testing process have increased exponentially.
But did you know that most businesses are still not using software testing automation to its full potential?
In the past couple of years in particular, AI and machine learning have broadened the scope of what testing automation can do significantly - think 'test automation but in hyperdrive'.
AI tools can model real-world scenarios instantly, use machine learning to generate test cases, auto-correct element selection in tests when the UI changes, and so much more. That's hours of your engineers' time that you can reinvest back in project work.
"Momentic makes it 3x faster for our team to write and maintain end to end tests."
Alex Cui, CTO, GPTZero
We'd love to see if Momentic could help you optimize your software testing life cycle.
If, like Alex and his team, you're keen to save over two thirds of the time you spend on key testing processes, why not schedule a conversation with our founder?