I have started an RFC to integrate rsvg-rs into librsvg.
rsvg-rs is the Rust binding to librsvg. Like the gtk-rs bindings,
it gets generated from a pre-built GIR file.
It would be nice for librsvg to provide the Rust binding by itself, so
that librsvg's own internal tools can be implemented in Rust —
currently all the tests are done in C, as are the rsvg-convert(1) and
rsvg-view-3(1) programs.
There are some implications for how rsvg-rs would get built then.
For librsvg's internal consumption, the binding can be built from the
Rsvg-2.0.gir file that gets built out of the main librsvg.so. But
for public consumption of rsvg-rs, when it is being used as a normal
crate and built by Cargo, that Rsvg-2.0.gir needs to be already
built and available: it wouldn't be appropriate for Cargo to build
librsvg and the .gir file itself.
If this sort of thing interests you, take a look at the RFC!