Demi Marie Obenour <demiobenour@gmail.com> writes:

> On 12/8/25 19:38, Alyssa Ross wrote:
>> This means we can use readiness notification to wait until the sockets
>> are created without having to add special functionality for that to
>> the router program, and also means we can do extra system-specific
>> setup to the sockets, like changing their owners, outside of the
>> router.
>> 
>> Since the socket paths were the only arguments taken by the router,
>> this also lets us drop the clap dependency entirely.
>
> I strongly recommend open-coding the file descriptor stuff instead
> of using a third-party library for it.  It's just a two calls to
> getsockopt() (SO_DOMAIN and SO_TYPE) per socket, and listenfd pulls
> in wasm-bindgen and js-sys!

It pulls in wasm-bindgen and js-sys if you're building for those
platforms, which we are not.  An inert mention in Cargo.lock is not a
problem.  The only dependency of listenfd in our context (checked via
cargo tree) is on libc, which is already a dependency of tokio.

I've implemented systemd socket activation in Rust before, and it's not
at all nice, even with libsystemd.  listenfd adds 295 extra lines of
code in total.  I think that's worth it.