He&#x27;s probably refering to itkacl, which we use for authorization&#x2F;acls (not payments). The README (and the code) can be found here: <a href="https:&#x2F;&#x2F;git.sesse.net&#x2F;?p=itkacl;a=blob;f=README;h=3dcb059f306140838f22dd6fd8541a5a9e5a26b8;hb=HEAD" rel="nofollow">https:&#x2F;&#x2F;git.sesse.net&#x2F;?p=itkacl;a=blob;f=README;h=3dcb059f30...</a>