RSpec 4.0 adds improved DSL and Rails 6.1 compatibility
RSpec 4.0 improves developer experience with a cleaner DSL, better introspection, and full support for Rails 6.1 features including Action Mailbox, Action Cable, and Zeitwerk.
GAURAV VARMA
RSpec 3.9 adds example filtering and failure grouping
RSpec 3.9 improves test organization with grouped failures and enhanced filtering options for large test suites.
RSpec 3.8 improves test isolation with faster bisect
RSpec 3.8 brings enhancements to test debugging, including a faster `--bisect` feature that helps isolate test order dependencies efficiently.