Hi,

I'm a rust noob trying to package the crate boringtun using
debcargo-conf. When trying to build it, the following build dependencies
are being generated but missing:

librust-x25519-dalek-2.0+default-dev (<< 2.0.1-~~)
librust-x25519-dalek-2.0+reusable-secrets-dev (<< 2.0.1-~~)
librust-x25519-dalek-2.0+static-secrets-dev (<< 2.0.1-~~)

I was told by the folks in #debian-rust that src:rust-curve25519-dalek
already packaged the x25519-dalek crate and that one possible solution
to my issue would be if librust-x25519-dalek-dev would provide its
virtual package with a "2.0" instead of just a "2" in their name.
Indeed, librust-x25519-dalek-dev provides:

librust-x25519-dalek-2+default-dev (= 2.0.1+4.2.0+dfsg-1)
librust-x25519-dalek-2+reusable-secrets-dev (= 2.0.1+4.2.0+dfsg-1)
librust-x25519-dalek-2+static-secrets-dev (= 2.0.1+4.2.0+dfsg-1)

The difference in the name is the "2" versus the "2.0". Would that be
possible?

Thanks!

cheers, josch

Hi Johannes,

Quoting Johannes Schauer Marin Rodrigues (2025-10-01 17:42:36)

What is the purpose for such declaration?

I am aware that Rust team tooling automatically generates such tight
package relation declaration, but why?

According to (my understanding of) semver specification, There should
be no structural reason to need feature "default" more narrowly than
the level of a stable version "2".

The reason I avoid providing it is that a) I see no need for it, and
b) it bloats the Debian packaging database.

 - Jonas

Hi Jonas,

Quoting Jonas Smedegaard (2025-10-07 06:31:26)

unfortunately I'm unable to answer your question. I am very new to Rust as a
language and Rust packaging in Debian in particular. I am thus not familiar at
all with the best practices which existing teams established already and will
leave it up others to answer your question in a better technical capacity than
I would be able to. :)

Thank you for maintaining the x25519-dalek crate in Debian!

cheers, josch

Quoting Johannes Schauer Marin Rodrigues (2025-10-08 19:28:22)

Fair enough. Sorry, I did not intend to challenge you - you did already
initially mention that you were new in the Rust team.

This question has come up before in the past, but I don't recall where
(possibly in a discrete conversation). I will keep this one open, but
tagged wontfix and moreinfo until clarified why it is needed.

Thanks for asking.

 - Jonas