You can manage individual certs with cert objects that aren't used by ingresses.
17 karma · joined October 6, 2016
* it does not support subdomains (only root domains)
* it only supports googlecloud as dns provider
* Bugs and PRs remain unanswered/unmerged
Meanwhile the linked project supports http, SNI and DNS challenges, with around 20 or so DNS providers available. It also supports managing certs for ingress objects directly.