Engineering English
Jest
Software Engineering · Last updated: July 30, 2026 · How this entry was written
Definition: Jest is a JavaScript testing framework designed for simplicity, supporting unit and integration tests with built-in mocking and code coverage. It is widely used with React and other frontend libraries.
Example in context
“Before deploying, the developer runs Jest to verify that all unit tests pass and that code coverage meets the threshold.”
“Before deploying, the developer runs Jest to verify that all unit tests pass and that code coverage meets the threshold.”
Where engineers use it
Jest is commonly run in development and CI pipelines to catch bugs early. Engineers set up test suites with mock functions and snapshot tests to ensure code quality.
Practice: can you use “Jest” at work?
A team's CI build is failing due to a test failure. They need to check the Jest output and fix the failing test.
Show a model answer
“Run Jest with the --coverage flag to generate a test coverage report.”
“Jest” in 21 languages
| English | Jest |
|---|---|
| Turkish | Jest |
| French | Jest |
| German | Jest |
| Spanish | Jest |
| Chinese | Jest |
| Arabic | جيست |
| Portuguese | Jest |
| Russian | Джест |
| Japanese | Jest |
| Italian | Jest |
| Vietnamese | Jest |
| Hindi | जेस्ट |
| Thai | เจสต์ |
| Indonesian | Jest |
| Korean | 제스트 |
| Bengali | জেস্ট |
| Dutch | Jest |
| Swedish | Jest |
| Finnish | Jest |
| Ukrainian | Джест |
Frequently asked questions
What does Jest mean in engineering?
Jest is a JavaScript testing framework designed for simplicity, supporting unit and integration tests with built-in mocking and code coverage. It is widely used with React and other frontend libraries. In Software Engineering, the term carries a usage-frequency rating of 10/10 in the Engineering English library.
How do you pronounce Jest?
Jest is pronounced /dʒɛst/ (IPA). The Engineering English app plays audio for the term and checks your pronunciation with speech recognition.
How is Jest used in a sentence?
Example from an engineering context: “Before deploying, the developer runs Jest to verify that all unit tests pass and that code coverage meets the threshold.”
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