chore: describe how to run tests in README

README.md

@@ -297,7 +297,30 @@ An entity will be a json object, whose keys are defined by its EntitySchema
 
 ## Tests
 
-Running the test suite requires nodejs, mocha and xhr2.
+The tests relies on an instance with the `test-server` cube to run.
+
+The Dockerfile located in `test-server` creates an image with an instance ready for
+use. Building it is as simple as:
+
+```bash
+docker build -t cw-test-server .
+```
+
+You can then run the instance using `docker run`:
+
+```bash
+docker run -p 8080:8080 cw-test-server
+```
+
+Once the instance is running, launch the tests:
+
+```bash
+npm run test
+```
+
+By default the test instance is running on "http://localhost:8080". If you need
+to start it on a different host/port, use the `CW_BASE_URL` environment
+variable.
 
 ## Known issues