Cucumber is made up of several libraries, many of which are kept in polyglot repositories, meaning we keep multiple language implementations of the same library together in the same repo.

Library	Description	Latest release
cucumber-expressions	Pattern-matching for Gherkin steps
tag-expressions	For parsing tag selection queries
gherkin	Parser for Gherkin feature files
messages	JSON message protocol
query	Query API for messages
gherkin-utils	API for querying parsed Gherkin documents

If you're not sure which repository your issue belongs under, or it cuts across multiple repos, raise it in this repo.