Codacy - Automatically reviews code style, security, duplication, complexity, and coverage on every change while tracking code quality throughout your sprints.
CodeStream - CodeStream helps development teams resolve issues faster, and improve code quality by streamlining code reviews inside your IDE
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Refactor.io - Share your code instantly for refactoring and code review
DeepSource - Automated code reviews with static analysis.
JetBrains Qodana - Evaluate the integrity of code you own, contract or purchase