How to run scenarios in Cucumber-JVM in parallel?

This question already has an answer here:

How to execute cucumber feature file parallel 4 answers

I have a set of acceptance tests written for the Cucumber-JVM. In order to reduce the feedback time I would like to run the scenarios (of a feature) in parallel. How do I do that in the simplest and most convenient way?

(I would prefer to be able to express this in Java code, as a regular JUnit test/runner, i.e. I would prefer not to resort to some workaround using the maven-surefire or maven-failsafe plugin which would require(?) twiddling and merging of the Cucumber reports afterwards.)

Due to the nature of the cucumber-jvm package, test parallelization is limited for the time being. There are tentative plans for the future to change the API (gherkin3, cucumber-jvm v2), but nothing is available for full parallelization now on the cucumber-jvm.

There is still a way to attain a degree of parallelism on the cucumber-jvm. The Zucchini package (https://github.com/Comcast/Zucchini) can help by providing context-level parallelism, which could help if you have to run a battery of tests against Android / iOS / Chrome / etc. Test results are then merged into a single report.

To start using Zucchini, create a new test class that extends AbstractZucchiniTest and is tagged with @CucumberOptions and ZucchiniOutput. The class should then implement the List<TestContext> getTestContexts() method that returns a list of your specialized contexts.

Zucchini also provides other features such as cross-context barrier synchronization and aggregated test output into an HTML report. If you already have cucumber tests, there isn't much involved in upgrading them to Zucchini tests.