Manual talk:Composer.json best practices

The page says that extensions should depend on composer/installers to make themselves installable, but doesn’t specify how exactly this should be done. Composer/For extensions#composer.json specifies the version >=1.0.1, which is also found in several extensions “in the wild”, but that results in a warning from composer due to the “unbound version constraint”. composer/installers’ own documentation recommends ~1.0 – any problems with that?

The Bootstrap extension linked to as a “good example” in the Extensions section is no longer mirrored on GitHub, and on Gerrit it’s archived with a comment pointing to https://github.com/cmln/mw-bootstrap instead. Does it still qualify as a good example? (I didn’t want to just fix the dead link because the link text “mediawiki/extensions/Bootstrap” might no longer be appropriate.)