This is a great comment. As a small addition to this, a good technique to assess if your unit tests are able to catch behavior changes in an application when the code changes is Mutation Testing.

This is a small explanation and demo I made recently with Stryker, a framework for the JavaScript ecosystem https://github.com/peter-evans/mutation-testing

This is a good list of available frameworks in other languages: https://github.com/theofidry/awesome-mutation-testing

Rakuten | Software Engineer | Setagaya, Tokyo, Japan | ONSITE | Full Time

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Seeking experienced server side engineers to develop backend services for smart device applications. Full description and application process here: https://jobs.rakuten.careers/careersection/rakuten_ext_cs/jo...

Rakuten | Software Engineer | Setagaya, Tokyo, Japan | ONSITE | Full Time

Tech: Java, Spring Boot, Docker, Kubernetes, MQ messaging, Google Container Engine.

Seeking experienced server side engineers to develop backend services for smart device applications. Full description and application process here: https://jobs.rakuten.careers/careersection/rakuten_ext_cs/jo...

Rakuten | Software Engineer | Setagaya, Tokyo, Japan | ONSITE | Full Time

Tech: Java, Spring Boot, Docker, Kubernetes, MQ messaging, Google Container Engine.

Seeking experienced server side engineers to develop backend services for smart device applications. Full description and application process here: https://jobs.rakuten.careers/careersection/rakuten_ext_cs/jo...

Rakuten | Software Engineer | Setagaya, Tokyo, Japan | ONSITE | Full Time

Tech: Java, Spring Boot, Docker, Kubernetes, MQ messaging, GKE, Azure.

Seeking experienced server side engineers to develop backend services for smart device applications.

Full description and application process here: https://jobs.rakuten.careers/careersection/rakuten_ext_cs/jo...