Thread:Skin talk:Chameleon/Composer Installer Version/reply

As far as I can see, 1.0 has not been tagged therefore a stable 1.0 release is not yet available. If you would like to use the development version  should work otherwise you should wait until the official 1.0 via packagist.org is available.

{ "minimum-stability" : "dev", "require": { "mediawiki/chameleon-skin": "dev-master" } }