diff --git a/CONTRIBUTING.md b/CONTRIBUTING.md
index fd990cbb..da31ce23 100644
--- a/CONTRIBUTING.md
+++ b/CONTRIBUTING.md
@@ -190,6 +190,36 @@ When debugging the CMS with Git Gateway you must:
     4. Refresh the page
     5. You should be able to log in via your Netlify Identity email/password
 
+### Fine tune the way you run unit tests
+
+There are situations where you would want to run a specific test file, or tests that match a certain pattern.
+
+To run all the tests for a specific file, use this command:
+
+```
+yarn jest <filename or file path>
+```
+
+The first part of the command, `yarn jest` means running the locally installed version of `jest`. It is equivalent to running `node_modules/.bin/jest`.
+
+Example for running all the tests for the file `gitlab.spec.js`: `yarn jest gitlab.spec.js`
+
+Some test files like `API.spec.js` is available in several packages. You can pass a regexp pattern instead of file path to narrow down files.
+
+Example for running all the tests for the file `API.spec.js` in the `netlify-cms-backend-gitlab` package:
+
+`yarn jest ".+backend-gitlab/.+/API.spec.js`
+
+To run a specific test in a file, add the flag `--testNamePattern`, or `-t` for short followed by a regexp to match your test name.
+
+Example for running the test "should return true on project access_level >= 30" in the API.spec.js in `netlify-cms-backend-gitlab` package:
+
+```
+yarn jest -t "true on p" ".+backend-gitlab/.+/API.spec.js"
+```
+
+For more information about running tests exactly the way you want, check out the official documentation for [Jest CLI](https://jestjs.io/docs/cli).
+
 ## License
 
 By contributing to Netlify CMS, you agree that your contributions will be licensed