YAML files can now be created, read, updated, and deleted directly on CINC.io. Previously, the only way to get YAML into a project was to import it, so CINC.io was effectively just a storage tool (with versioning) for your Drupal configuration. Public storage is useful by itself, as it allows us to share configuration between Drupal sites. But CINC.io is intended to do more than improve how we share configuration; it should also improve how we make configuration.
To try out this new functionality, simply create a project and visit the project page. When the site recognizes you as the owner of a project, the YAML viewing interface is automatically converted into an editing interface. The editing interface is very simple right now. I'll be adding more advanced interfaces targeting specific workflows and configuration types, but first I wanted to provide a general interface that would be useful in any workflow. This initial interface is effectively the "view source" of a Drupal configuration project, so you can see exactly what other tools are doing.
The new editing interface is also built on a full RESTful API, which will be a good basis for future interfaces to manage Drupal configuration. I'll be creating these interfaces directly on CINC.io, but the API isn't limited to CINC.io; anyone can use the CINC.io API to create Drupal configuration interfaces anywhere. The Drupal CINC module provided a good platform for creating new configuration interfaces in Drupal, and now CINC.io provides a good platform for creating Drupal configuration interfaces in any environment or programming language.