@Maelstrom96 said in Icon appears in the XOA interface:

do you have pointers on how to build a slackware package for xe-guest-utilities?

If you still want to have a try at building (even though that will not let XO show an icon) the first question is, do you really want to build a slackware package (as in "contribute a package to Slackware so it is available to all Slackware users), or just get it built.
In the latter case, @TeddyAstie answered already, but if you really want to get into packaging, you should look on the Slackware side (e.g. here). I would have added "you may also want to have a look at any existing packaging of a Rust program", but given how "unstructured" the whole thing seems to be (I stand quite surprised of those 1995-looking all-manual instructions), you should be able to build a package once you've built the binary using rustup.