Arkadiusz Krysik

SDLC Guide: Key Steps of Software Testing Process

Have you ever wondered how software developers ensure that the applications you use every day are reliable and bug-free?

The answer lies in the process of software testing – a critical phase in the Software Development Life Cycle (SDLC).

In this article we are going to examine the various stages of software testing, from initial planning to execution and reporting. We will show you the different types and approaches to testing, each of which plays a critical role in refining and validating software to ensure it meets the highest standards of quality and functionality before it reaches users.

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What is software testing?

Software testing is an important stage in the software development process during which software developers test software to ensure that it works properly.

This process involves running the software under controlled conditions to verify that it behaves as expected, meets the specified requirements, and ensures quality.

The primary goal of software testing is to identify defects, gaps, or any inconsistencies between the existing and desired conditions in the software. It includes various methods and levels, such as unit testing, integration testing, system testing, and acceptance testing, each of which addresses specific aspects of the software.

testing procedure static testing

It’s like giving the software a test run to find any bugs or problems before it’s used for real tasks. This testing helps ensure that the software does exactly what it’s supposed to do, without errors or problems.

It’s a bit like proofreading a document or inspecting a car before you buy it – you want to catch any problems early.

In an enterprise, software testing helps save time and money by ensuring that the software is reliable and can be trusted to perform well. It’s a critical step in ensuring that the technology a company uses is effective and won’t cause unexpected problems.

[Read also: SDLC Guide: Requirement Analysis in Software Engineering]

Coding and testing phase in SDLC

In the software development process, the development and testing phases are inextricably linked and mutually beneficial, forming a complementary relationship that is critical to producing high-quality software.

During the development phase and design phase, software engineers design, write, and assemble the code to create a working application.

At the same time, the testing phase, in which the software is rigorously evaluated to identify and correct any defects or problems, ensures that the software not only meets the specified requirements but also adheres to quality standards.

By integrating testing early and continuously throughout the development cycle, potential problems can be identified and addressed earlier, reducing the cost and time of fixing them later. This collaboration between development and testing teams improves the overall quality of the software by providing immediate feedback and iterative improvements.

test data dynamic testing

Why is software testing process important?

The importance of the software testing process in software development cannot be overstated, as it plays a critical role in ensuring the quality, reliability, and performance of the software product.

First, it identifies bugs and errors that could potentially lead to software failure, thereby preventing costly and potentially harmful consequences after deployment.

Second, software testing verifies that the software meets the specified requirements and user expectations, which is essential for customer satisfaction and confidence.

Testing also evaluates and optimizes the performance, security, and usability of the software, contributing to a better user experience. In essence, the software testing process is essential to delivering a quality software product that is reliable, user-friendly, and fit for its intended purpose.

Types of software testing

Software testing is a diverse and complex field, encompassing a wide range of types of software testing, each designed to meet specific objectives and address different aspects of the software.

This diversity of test types is essential, as it allows for a comprehensive evaluation of the software from different angles, ensuring its functionality, reliability, and usability.

To better understand this topic, we’ve prepared this handy infographic that divides software testing types into 4 different levels, with functional and non-functional testing types being the broadest.

non functional testing

They refer to the testing of different objectives of the software. Functional testing tests the specific actions and features of the software, while non-functional testing evaluates overall performance, usability, and reliability.

But there are also three different ways to perform software testing – these are on the first level of our diagram.

Manual testing involves human testers performing tests manually without the aid of automation tools, focusing on exploring and evaluating the software’s features and functionalities.

Automated testing uses software tools to run tests repeatedly and quickly, providing an efficient way to check for defects, especially in large and complex systems.

Continuous testing integrates testing into every phase of the software development lifecycle, providing continuous quality assurance and rapid feedback on potential problems.

testing team

Let’s take a closer look at these lower levels of our diagram and talk briefly about all the different types of functional and non-functional software testing:

top developers

Unit testing

Unit testing, a fundamental practice in software development, involves testing individual units or components of a software application in isolation.

A unit is the smallest testable part of a piece of software and typically has one or a few inputs and usually a single output. Unit testing is critical because it helps identify and fix bugs early in the development cycle, reducing cost and time to market. It also ensures higher product quality, which is essential for maintaining customer satisfaction and trust.

Regression testing

Common unit tests may include:

  • Data flow testing,
  • Branch coverage testing,
  • Control flow testing,
  • Statement Coverage Testing.

Integration testing

Integration testing is another critical subtype of functional testing in software development that focuses on testing software application’s components and how they interact with one another.

The primary objective of this testing is to identify issues that occur when units are combined and interact with each other.

System integration testing step is essential in the development process, particularly for complex systems where different modules or services must work together seamlessly. In a business context, integration testing is vital for ensuring that the integrated components function correctly and meet the business requirements.

[Read also: Off the Shelf vs Custom Software: Pros & Cons + Examples]

User acceptance testing

User Acceptance Testing (UAT) is a critical phase in the software development process where end users test the software to verify that it performs the required tasks in real-world scenarios according to the specifications.

Within UAT, there are two main subtypes: alpha and beta testing.

testing tools

  • Alpha Testing: Conducted by internal staff, often in a controlled environment, to identify bugs and issues before the software is released to external users.
  • Beta Testing: Involves distributing the software to a group of external users to test in real-world conditions. This phase collects feedback on the software’s performance and user experience, which is crucial for making final adjustments before the official market release.

Performance testing

Now let’s move on to non-functional testing with the first type – performance testing.

In this type of software testing, the testing team focuses on evaluating the speed, responsiveness, and stability of a software application under various conditions.

This type of testing is essential to ensure that the software performs well in terms of speed and handling under expected workload scenarios. It enables companies resolve problems related to response times, low latency, throughput, and resource usage. By proactively addressing performance issues, organizations can increase user satisfaction, reduce downtime, and improve customer retention. It doesn’t matter if you a robust enterprise software accounting system, a metasearch travel engine, or a custom search engine, software performance is critical to all of these projects in all branches of business.

Subtypes of performance testing include:

  • Stress Testing: Determines how the software behaves under extreme workloads, testing its limits and identifying its breaking point.
  • Load Testing: Evaluates the software’s performance under expected user loads to ensure it can handle anticipated traffic without degradation of performance.
  • Endurance Testing: Checks the software’s ability to sustain the expected load over an extended period, ensuring reliability over time.
  • Spike Testing: Assesses the software’s reaction to sudden large spikes in user load, such as a surge in web traffic, to ensure it can handle abrupt changes in demand.
  • Soak Testing: Involves testing the software under a significant load extended over a long duration to identify issues like memory leaks.
  • Scalability Testing: Determines the software’s effectiveness in scaling up or down in response to varying loads, ensuring it can adapt to growth and change in user demand.

Security testing

Security testing, another important component of non-functional testing in software development, focuses on identifying vulnerabilities, threats, and risks in a software application to prevent malicious attacks.

In today’s digital age, where cyber threats are increasingly sophisticated and pervasive, security in soiftware development has become more important than ever.

For SaaS and web applications, there are continuous security scanning tools such as Scanrepeat that provide continuous monitoring and immediate detection of security vulnerabilities, helping to maintain the integrity and trustworthiness of the software over time.

There are two general types of security testing:

  • Penetration Testing: Simulates an attack from a malicious hacker to identify and exploit weaknesses in the software’s security, revealing how well the system can defend against real-life attacks.
  • Vulnerability Testing: Involves systematically scanning the software to identify known vulnerabilities, such as unpatched flaws or outdated software components, ensuring that these weaknesses are addressed proactively.

Compatibility testing

Now, let’s briefly describe the last type of software testing we’ll talk about in this article – compatibility testing.

It focuses on evaluating whether a software application or product works as intended across different browsers, databases, hardware, operating systems, mobile devices, and networks. The primary goal is to ensure that the software is compatible with different environments and configurations, which is critical in today’s diverse technology landscape.

Key steps of software testing process

let’s now delve into the intricate stages of the software testing process.

From the preliminary assessment to the detailed execution and final analysis, each step is crucial.

Here, we break down these stages of the software testing process, providing clarity on how they collectively ensure the delivery of high-quality, reliable software.

test scripts software testing tools

Step 1: Assess the Development Plan and Status

This initial step involves understanding the overall development plan, project scope, and current status.

It’s about getting a clear picture of what has been developed, what functionality needs to be tested, and aligning testing goals with development goals.

Step 2: Develop the Test Plan

The second step involves strategizing the testing process just like we did with the entire development project during the software development planning stage.

This includes defining the scope of testing, selecting testing methodologies and tools, outlining the test plan, and allocating resources. The test plan acts as a roadmap for testing activities, ensuring that the testing effort is organized and efficient.

Step 3: Create Test Cases

In this phase, testers develop specific test cases based on the requirements and objectives outlined in the test plan.

Test cases are detailed instructions that describe what needs to be tested, how to test it, and the expected results. This step is crucial for ensuring that all aspects of the software are thoroughly tested.

Step 4: Setup Test Environment

Setting up the test environment involves preparing the hardware and software necessary for executing the test cases.

This environment should mimic the production environment to accurately assess how the software performs under real-world conditions.

Step 5: Execute Your Tests

Now comes the time for execution of the tests themeselves.

Testers run the software through the developed test cases, observe its behavior and performance, and record the outcomes. Any deviations from the expected results are logged as defects for further investigation.

Step 6: Report Test Results

After testing is complete, the results are compiled into a report.

This report details the testing process, the defects found, and an assessment of the software’s quality. It is a crucial document that informs stakeholders about the state of the software and any risks associated with its release.

Software testing – Tips from experts

Software testing is a nuanced field, but it’s critical to delivering high-quality software solutions.

That’s why we asked our senior developers to share some tips on test execution strategies and best practices. Here is what they had to say:

continuous testing

Cover your code with tests right from the beginning

Start writing tests as soon as you start coding.

Early testing helps catch bugs when they’re easier and less expensive to fix. It also encourages you to write more testable, and therefore more structured, code. Think of tests as a safety net that grows with your codebase, ensuring that each new feature or function works as intended and continues to work as the system evolves.

Realistically simulate production environment

For software testing to yield tangible results, it is important to run it on data sets and hardware that are as close to production as possible.

Especially in the case of enterprise software, it is sometimes difficult to get information about the expected “shape and size” of the data that the system will have to deal with in production. It is very important to discuss these criteria with the customer in advance in order to properly set up the test environment.

Automate as much as you can

There’s this popular saying: work smart, not hard.

In the case of software development that means that test automation is the key to efficient software testing.

Automated tests save time, reduce human error, and can be run frequently. Focus on automating repetitive tasks, regression tests, and other time-consuming tests that are run frequently.

Keep in mind, however, that not everything can or should be automated; some scenarios still require the nuanced judgment of manual testing.

Don’t focus on microbenchmarks

While performance testing is important, avoid getting bogged down in micro-optimizations at the expense of overall system performance.

It’s easy to fall into the trap of optimizing small pieces of code for performance gains that don’t have a significant impact on the overall application. You might spend hours tweaking a piece of code that improves the performance of the software by a tiny margin when your time could have been spent more efficiently elsewhere.

Instead of focusing on microbenchmarks, focus on profiling and optimizing areas that will have a meaningful impact on the application’s performance.

Isolate your tests

If you have been reading about multitenant software architecture, you should not be a stranger to the concept of a noisy neighbor problem.

A similar thing can happen when conducting software tests. Performance testing capabilities can be negatively affected if the tests are run on the same hardware with other processes in the background.

Next step of the software development life cycle

After the software testing phase, the next critical step in the software development lifecycle is deployment.

Deployment is the process of making the software available for use, typically by transferring it from the development environment to the production environment.

Deployment is a critical step because it marks the transition of the software from a development phase to being operational and available to end users, but we will look at this stage in more detail in the next installment of our series on the SDLC. Stay tuned!


In summary, the software testing process, as an integral part of the Software Development Life Cycle (SDLC), plays a critical role in ensuring the delivery of high quality software products.

Through a variety of testing methodologies, from unit testing to acceptance testing, and with approaches ranging from manual to automated testing, developers can effectively identify and resolve issues, thereby improving the reliability and performance of the software.

We are Stratoflow, a custom software development company. We firmly believe that software craftsmanship, collaboration and effective communication is key in delivering complex software projects. This allows us to build advanced high-performance Java applications capable of processing vast amounts of data in a short time. We also provide our clients with an option to outsource and hire Java developers to extend their teams with experienced professionals. As a result, our Java software development services contribute to our clients’ business growth. We specialize in travel software, ecommerce software, and fintech software development. In addition, we are taking low-code to a new level with our Open-Source Low-Code Platform.

Building a new application or extending your development team?

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