Code Quality Overview¶
What You'll Learn¶
- Where SonarQube fits among linters, security scanners, and paid platforms
- The recommended path from installation to an enforced quality gate
- How the pages in this section build on each other
SonarQube helps teams check code quality and security issues as part of normal development and CI/CD work. It is useful when you want automated feedback on bugs, vulnerabilities, code smells, duplication, and quality gates.
SonarQube is one option in a much larger market — this section also maps the surrounding ecosystem of open-source linters, security scanners, and paid SaaS platforms so you can combine them deliberately.
What This Section Covers¶
- Installing SonarQube on Ubuntu
- Connecting SonarQube to PostgreSQL
- Integrating scans into Jenkins pipelines
- Open-source tools and libraries — ruff, ESLint, Checkstyle, SpotBugs, Semgrep, Gitleaks, Trivy, JaCoCo, and how to wire them into CI
- Paid and SaaS platforms — SonarCloud, GitHub Advanced Security (CodeQL), Snyk, Codacy, Qlty, DeepSource, Codecov, Veracode, Checkmarx
Why Teams Use SonarQube¶
- Finds quality and security issues early
- Supports many programming languages
- Adds quality gates to pull request and pipeline workflows
- Makes technical debt easier to track over time
Recommended Flow¶
- Install SonarQube
- Configure the database and service
- Connect Jenkins
- Add analysis to a pipeline
- Enforce a quality gate
Useful Links¶
Tip
For production use, plan for enough memory, persistent storage, backups, and proper access control from the start.
Common Mistakes¶
- Gating on overall code metrics instead of new code, so legacy debt blocks every change.
- Treating SonarQube as the only check instead of running fast linters locally and in CI first.
- Ignoring security hotspots because they aren't marked as bugs.
- Leaving the default admin password, and not backing up the database.
Interview Questions¶
- What is a quality gate, and what should it check?
- What does "clean as you code" mean?
- What's the difference between SAST, SCA, and secrets scanning?
Next¶
Continue to Open-Source Code Quality Tools.