According to a study, software failures cost the US economy an estimated $2.08 trillion in 2020 alone. Software development has become an integral part of almost every industry, with an increasing reliance on technology for business operations. As software development becomes more complex and the demand for faster releases increases, ensuring code quality has become more critical than ever. Poor code quality can lead to bugs, security vulnerabilities, and ultimately, a subpar user experience that can damage a company's reputation and bottom line.

Whether you're a seasoned developer or just starting, this guide will equip you with the knowledge and skills to elevate your code quality and deliver better results. So, let's dive in!

Importance of Code Quality in SDLC

Code quality is essential for any software development project. Poor code quality has led to significant consequences for various companies and organizations in the past. In the Equifax data breach, for example, hackers exploited a vulnerability in the company's web application due to poor coding practices, which resulted in the exposure of sensitive personal information of approximately 143 million individuals. This breach ultimately cost Equifax over $1.4 billion in settlements and damages, not to mention significant damage to its reputation.

Similarly, in the Target data breach, hackers were able to infiltrate the company's payment system and steal the credit card information of over 40 million customers. The breach was due to a vulnerability in the company's network due to inadequate coding practices. Target incurred a loss of $162 million in damages and settlements as a result of the breach. To avoid these, software development teams should ensure code quality is a top priority throughout the SDLC.

Steps to Ensure Code Quality in Custom Software Development

The following are the steps to ensure code quality in custom software development:

  1. Code Reviews: Code reviews allow developers to catch errors and inconsistencies before they make it into the production environment. Code reviews should be conducted regularly and by multiple developers to ensure the code is of high quality. A study by SmartBear found that code reviews can be an effective way to find bugs and take only 20% of the time taken by traditional practices.
  2. Automated Testing: Automated testing helps to ensure that code is thoroughly tested and can identify any bugs before the code is deployed. The use of automated testing tools can save time and increase the accuracy of testing.
  3. Continuous Integration and Delivery (CI/CD): CI/CD helps to automate the software development process by integrating code changes and automatically testing and deploying code. This reduces the risk of human error and speeds up the software development process. The software development company, Shopify, deploys code to production multiple times per day using a CI/CD pipeline.

Explore here the Importance of CI/CD in full stack software development.

Techniques for Improving Code Quality in SDLC

The following are the techniques for improving code quality in SDLC:

  1. Code Refactoring: Refactoring is the process of improving existing code without changing its external behavior. Refactoring helps to remove code duplication, simplify code, and make it easier to maintain.
  2. Code Documentation: Proper code documentation helps to understand the code's functionality and its purpose. It also helps to reduce the risk of bugs and increase the code's maintainability. The open-source software company, Red Hat, has a policy of requiring all code submissions to be accompanied by documentation, which they credit with improving code quality and reducing the need for future bug fixes.
  3. Code Testing: Comprehensive testing of the code is crucial for detecting bugs and errors. It helps to ensure that the code meets the requirements and is of high quality. The software development company, Microsoft, found that implementing automated testing reduced the number of bugs significantly.

How to Measure Code Quality: Code Quality Metrics

Code quality metrics are measures that indicate the quality of the code. The following points tell you how to improve code quality:

  1. Code Coverage: This metric measures the percentage of code that has been tested. The higher the coverage, the better the quality of the code. A tool like Jacoco can be used to measure code coverage.
  2. Cyclomatic Complexity: This metric measures the complexity of code. The higher the complexity, the more difficult it is to maintain and test the code. A tool like SonarQube can be used to measure cyclomatic complexity.
  3. Code Duplication: This metric measures the amount of duplicate code in the project. Duplicate code can cause maintenance issues and decrease code quality. A tool like Simian can be used to detect duplicate code.
  4. Code Smells: Code smells are indications of poor design or implementation choices that can lead to bugs and maintenance issues. Tools like PMD and Checkstyle can be used to identify code smells.
  5. Defect Density: This metric measures the number of defects per line of code. The lower the defect density, the better the quality of the code. A tool like SonarQube can be used to measure defect density.
  6. Maintainability Index: This metric measures the ease of maintaining the code. The higher the maintainability index, the easier it is to maintain the code. A tool like Visual Studio can be used to measure the maintainability index.
  7. Code Review Feedback: Code review feedback is a qualitative measure of code quality. Code reviews provide an opportunity for peers to review and provide feedback on code quality. Tools like GitHub and Bitbucket provide features for code review.

Code Quality Check

To ensure code quality, software development teams should conduct regular code reviews, automated testing, and CI/CD. They should also follow best practices such as code refactoring, code documentation, and code testing. The use of code quality metrics can help to measure and improve the code quality.

Code quality is an essential aspect of software development, and poor code quality can lead to significant consequences such as costly software failures and data breaches. To ensure code quality in SDLC, software development teams should follow best practices such as regular code reviews, automated testing, and CI/CD. They should also use techniques such as code refactoring, code documentation, and code testing to improve the code's quality. Additionally, the use of code quality metrics can help measure and improve code quality, ultimately delivering better software to customers.

Also explore our previous blog, Quality Assurance vs Quality Control: What's the Difference?