If this parameters are not skipped, they are sent as null and some clients (at least, Riot) coerces them to 0.
ruma-events
ruma-events contains serializable types for the events in the Matrix specification that can be shared by client and server code.
Minimum Rust version
ruma-events requires Rust 1.40.0 or later.
Documentation
ruma-events has comprehensive documentation available on docs.rs.