How to Improve Code Quality:
8 Proven Steps

High code quality is essential and something developers should pursue. Yet many companies face a problem: determining whether their code is good or bad. Luckily, industry best practices assist with this.

In this article, we will offer guidance, deep insights, practical examples of good code, and methods to measure code quality. We will focus on software development practices and principles of code quality. We also want to teach you how to maintain the quality of your codebase as you update and extend it over time.

The quality of code is subjective. So, it’s best we explain what it is.

Code quality describes how code achieves its purpose and how easy it is to maintain.

“Good” depends on company standards, requirements, and risk tolerance. However, there are best practices and key characteristics of a “good” quality of code:

• Code readability: Clear naming, structure, formatting, and flow that make the code logic understandable to developers
• Consistency: Uniform style across the project that makes the code less confusing, especially for onboarding developers
• Performance: Code completes its tasks with minimal resources and actions, such as unnecessary loops and if statements
• Maintainability: How easy it is to adjust existing code without breaking
• Reliability: Whether the product stays stable under heavy activity loads and unusual usage scenarios
• Testability: Ability to test code without affecting the rest of the codebase
• Security: Code doesn’t introduce critical vulnerabilities

Long story short: You want to write code that does its job well without creating problems.

Low-quality code causes bugs and security issues. It constrains your development pace and may force you to pay a lot more. A small mistake can snowball into a system-crashing error.

High-quality code matters because it influences the development process, operating costs, and end product in the following ways:

• Reducing bugs: Clean, predictable code produces fewer issues, reducing outages and long debugging cycles.
• Lowering costs: Fewer bugs early on mean developers spend less time repairing issues and optimizing the codebase to reduce technical debt.
• Accelerating delivery: Software code that follows quality standards is more understandable and, as a result, easier to maintain and update.
• Improving collaboration: Consistent coding patterns and style make it easier for teams to work together on the codebase without stepping on each other’s changes.
• Strengthening reliability: High-quality code makes the product more reliable under intense loads and edge usage scenarios.
• Boosting performance: Efficient code reduces delays and resource waste, improving the user experience.

Improving code quality should be a top priority for any software development project. But it’s not always easy to distinguish between the two.

How do you ensure code quality? To start off, you need to understand which parts of your codebase are up to standards that are more or less shared in the industry.

Traits of Good Code

High-quality code is understandable, efficient, and easily upgradable. Its key characteristics include:

• Consistent coding practices, such as appropriate variable naming, formatting, and structure
• Clearly expressed intent, with functions and modules having a clear purpose and expected behavior
• Adherence to the “Don’t Repeat Yourself” principle, using shared logic and reusable functions instead of copy-pasting code fragments
• Thoroughly documented and commented, explaining all sensitive rules, key modules, public interfaces, and logic decisions
• Modular and upgradable, with the codebase split into smaller, less dependent pieces of software with clear boundaries and clear functions
• Covered by meaningful tests, so all important logic paths, integration, and edge cases are thoroughly verified and reviewed

Traits of Bad Code

Poor quality code is usually cluttered, overly complex, and full of unnecessary (or dead) logic. The key traits include:

• Unnecessary complexity that hides real intent behind long functions, deeply nested if conditions, and unclear responsibilities
• Unstable code with tangled logic, where even small modifications produce myriad unexpected issues
• Absence of uniform style, with naming and flow patterns varying from block to block
• Lack of meaningful comments that leave many functions and logic vague or difficult to explain
• Repeated logic and dead code that were left without updates after significant requirements changes or updates

If you identify a considerable number of bad or questionable characteristics, it’s best to conduct a thorough optimization.

Companies may approach quality improvement differently. Below are strategies DevCom uses to ensure code quality and best practices and to keep codebases clear, stable, and scalable.

1. Establish code standards

Establishing standards for code writing is the simplest method to maintain coding quality and improve it over time. Code standards are syntax and style rules set for every developer. They decide everything from variable naming conventions to how functions are structured.

Store editor configs in the repository to ensure your team follows the same settings for a project. Such standards keep the structure predictable, so existing team members and new engineers spend less time decoding the style or trying to untangle the logic.

Take note of the existing standards for programming languages. For example, Java code quality standards are different from the Python ones. 

2. Select code review tools

High code quality should combine human code reviews with automated checks. You just need to know where to use each of them.

Use automated tools to flag unoptimized code, unused variables, or violations in naming conventions. Many developers use linters and formatting tools like ESLint, TSLint, Flake8, or Checkstyle to enforce these rules. 

Configure static analysis tools, like SonarQube, CodeClimate, and DeepSource. These will run on change, flagging code smells and duplications.

Developers and testers will need a checklist of sorts to use these tools efficiently. The checklist should cover different aspects of code quality checks.

3. Write automated tests

Automated tests confirm code behaves as expected. The goal is not to add more tests. To understand how to improve code quality, you need software testing to be relevant.

Make sure your cases cover critical paths and risky areas. It will help you catch important defects and performance bottlenecks before they reach production to save your engineers’ time later. 

You can build a priority structure for your testing. It can look like a pyramid: fast unit tests at the base, integration tests in the middle, and user journeys at the top.

Make sure your team learns from test results. This helps you improve code quality using error data.

4. Limit dependencies

A stronger design improves code quality. Modern applications sit on dozens of third-party libraries that handle core tasks, such as authentication, object mapping, and cryptography. If they are tightly coupled and full of interdependencies, the code becomes harder to test and update.

To improve source code quality, divide complex features into modular sections with fewer dependencies. Then, wrap external libraries inside small adapter classes or utility modules. This will allow your teams to modify large sections of the codebase without risking breaking other parts of the software.

5. Enable secure coding practices

Code commits, stored secrets, and new API routes can introduce security problems. While you can’t make development completely secure, adding checks into the entire software development lifecycle addresses many of these vulnerabilities before they accumulate into critical issues.

Validate and sanitize all commits entering the system, including request bodies, query parameters, and file uploads. Ideally, you should enforce access rules on every endpoint using role checks, object-level permissions, and rate limits.

Store API keys or passwords inside secure managers (Vault, Doppler, or AWS Secrets Manager). Make sure to rotate secrets and always analyze failed access attempts.

6. Clarify technical requirements

Requirements spell out how the system should behave. They should cover the regular and edge cases, clarifying inputs, outputs, and limits.

You need to clarify each aspect if you want to learn how to improve the quality of code. With more details, developers won’t improvise business rules and will instead prioritize what matters the most. 

Use a consistent format that captures the business goal, preconditions, inputs, outputs, and acceptance criteria for each software module. Pay special attention to edge cases, clear failure modes, empty inputs, boundary limits, and dependency failures.

7. Keep documentation up to date

Documentation describes how to ensure code quality as you rework your software or add new features. The last thing a team wants is for some parts of the software to be vague or unspecified.

Create a short briefing for each module that states its purpose, enforceable business rules, and expected behavior. If possible, build tables of concrete examples with real input and output values.

Rather than restating what the code already shows, comments should explain intent and provide context. Use annotations to explain why certain rules exist and what downstream behavior depends on this logic.

Store technical documents in the same repository under version control so updates move in step with code changes. Finally, you should log every modification, as it will help in ongoing code reviews and software code audits.

8. Refactor regularly

Refactoring consists of continuous code optimization. Even well-written code becomes outdated as the project evolves. Regular refactoring keeps the codebase performing well, preventing rising technical debt.

Reserve time in each development phase or sprint for small refactoring tasks rather than trying to rework whole modules at once. As you assess the quality of code, remove unused lines and obsolete feature flags to make code quality management easier later. Delete unused libraries to cut the number of dependencies and simplify debugging.

Last but not least, you must monitor quality signals. That’s where metrics come into play.

Code quality metrics are quantitative and qualitative indicators for your codebase’s health. 

Metrics turn abstract ideas about “good” code into concrete signals. Indicators like cyclomatic complexity and duplication highlight structural problems, risky areas, and oversights. They also reveal whether your codebase becomes more stable, more secure, and easier to extend.

How do you maintain code quality with these indicators? Learn more in our guide about code quality metrics and their implementation.

Reliable software depends on high-quality code. It should be easy to read, upgrade, and monitor by any team, as well as be free of exploits and vulnerabilities. This requires you to invest in coding standards, test cases, review tools, and documentation.

Yet, many development teams struggle to reach that level of code quality because they lack experience. It’s the previous work, not just skills, that makes it easier to review complex modules and coach junior developers.

DevCom can bring a specialist who not only conducts source code audit and optimization. We also mentor your in-house teams, helping them learn how to improve your code quality and maintain it going forward. Feel free to contact us to learn more about our services.