External registries
A login for a registry Cubeship does not run, so a private image there can be pulled — and browsed when the registry allows it.
A public image needs no login and no row here. A private one needs the instance to hold a login for its registry: one row per host, with a credential behind it.
Adding one
Registries → Add registry asks for the kind and the login. The credential is created in the same step — you do not go to Credentials first — and appears there afterwards, ready to be reused.
| Kind | What it asks for | Examples |
|---|---|---|
| Generic | the host, a username and a password or token | Docker Hub, GHCR, Gitea, Harbor |
| DigitalOcean | the registry's name and an API token | registry.digitalocean.com/<name> |
| AWS | the region, an access key id and its secret | ECR — the account id is discovered |
An ECR login is not a password: the stored key is used to fetch a token that Docker logs in with, which lasts hours and is minted again when it expires.
Matching is by host. A reference with no registry in it —
nginx, library/postgres — is Docker Hub.
What is fixed
The host and the kind, once the row exists. Re-pointing one in place would silently send every app that pulls from it somewhere else. What can change is which credential it logs in with — a second account, not a second address — from the registry's settings.
Rotating from the registry's settings rotates the credential, and everything else on it follows; the screen says which other things share it first.
Browsing
The dashboard picks an image from the registry's own catalogue when it offers one, and the tag from the repository, newest first. Two cases degrade rather than break:
- Docker Hub has no public catalogue, so the image is typed and the tag is listed.
- A registry may refuse its catalogue. Then the image is typed too.
From the registry's page an admin can delete a tag or a repository on the remote registry, where its API allows it.
Deleting
A registry that an app pulls from is still deletable — the app keeps its stored image reference and the next deploy fails on the login if the image is private. The credential behind it stays under Credentials until nothing uses it.
Not through an agent
There are no MCP tools for registries or credentials: creating one means a password passing through a model's context.