Third-party
Third-party crates are crates that aren't supported by the Twilight organization but are recognised by it. Of course, use these at your own risk. :)
Third-party crates may become first-party crates if they end up becoming useful enough for a large number of users.
List of Crates
Below is a list of crates. If you want yours added, feel free to ask!
baptiste0928/twilight-interactions
twilight-interactions provides macros and utilities to make interactions easier to use.
Its features include slash command parsing and creation from structs with derive macros.
GitHub repository - Documentation
Vesper Framework
vesper is a slash command framework meant to be used with twilight.
It uses procedural macros to make implementing slash commands as easy as possible and provides flexible argument parsing.
Modals are also supported making use of derive macros, so they can be used effortlessly.