Registries

Registries

Registries sits in the sidebar under Images. It lists where images come from and which of them this Mac is signed in to. It used to be a tab in Settings; it is a section now, with the same list as every other: rows with a checkbox, Sort, filter, a hover action and ⋮, multi-select, tags and the activity band, and the selected registry's page beside the list. See Views and filtering.

A convenience, not a limit

Apple's container has no list of supported registries. It pulls from anything that speaks the OCI distribution API, and the host at the front of the image reference decides where an image comes from: ghcr.io/owner/app comes from GHCR, whatever is in this list.

So the list is there to save you remembering hostnames and sign-in rules. It never restricts what you can pull, and the empty state and help text say so. You can pull from a registry that is not listed, and Flotilla will still show it if this Mac is signed in to it.

The list

A new install lists Docker Hub and GitHub Container Registry. The rest come from a catalogue of ten well-known public registries, each with one real hostname that does not depend on your account: Docker Hub, GHCR, Quay, Microsoft Artifact Registry, Amazon ECR Public, Kubernetes, Chainguard, GitLab, Red Hat Registry and Red Hat (no sign-in). Nothing from the catalogue is in your list until you add it.

A row shows the registry's Name and Tags, with its Server, Sign-in, Status and Type.

• Sign-in says whether that registry needs an account: Not needed (Microsoft and Kubernetes have no accounts at all), Optional (public images pull without one; signing in mainly raises your rate limit) or Required (Red Hat Registry serves nothing anonymously).
• Status says whether this Mac is signed in, and as whom. It comes from container registry list, so it needs container running. When it is not, one line above the list says the sign-in status is unknown, rather than every row claiming "Not signed in" about a Keychain nobody checked.

Badges beside a name:

• default — the registry Flotilla's Pull form completes a bare name against. See below.
• CLI default — Docker Hub, which is what container itself resolves alpine:latest to.
• yours — one you added.
• not in your list — this Mac is signed in to it, but it is not listed. Add to List adds it.

Adding a registry

Add Registry… asks what Type of registry it is before it asks for a server, because what people actually add are registries with no fixed hostname: private Amazon ECR, Azure, Google Artifact Registry, Harbor, JFrog Artifactory, Gitea or Forgejo, self-hosted GitLab, or a bare registry:2. What those share is not a host but how you sign in to that family, and that is what the form explains. Choose a type and the form shows a server of the right shape, and what goes in the username and password fields in that vendor's own terms.

Connect using is HTTPS unless the registry has no TLS at all, such as a development registry on your own network. It is remembered for that registry, unlike the Pull form's one-off switch. Over HTTP nothing can sign in: container 1.5 will not send a password unencrypted, so the form says so instead of offering a sign-in that can only fail.

Remove from List… deletes nothing — not the credentials and not any image. Add offers it again. Removing a row and destroying a credential are different decisions, so a registry you are still signed in to stays visible, marked not in your list, until you sign out.

Signing in

Choose a registry and enter a Username and a Password or token. Most registries want a token, not your account password, and several issue short-lived ones — Amazon's lasts about 12 hours, Google's about one — so expect to sign in again. Where the registry has a page for creating a token, Create a Token in Browser opens it, with the right scope already ticked for GitHub and GitLab. For GHCR, use a classic token with only read:packages: Flotilla never pushes, and ticking write:packages makes GitHub add full control of your private repositories with it.

Flotilla runs container registry login --password-stdin. The password goes to the command's input, never its arguments, because any process running as you can read another's arguments while it runs. Flotilla does not store it; container saves the credential in this Mac's Keychain.

Sign Out… deletes the stored credential from the Keychain. Public images still pull from registries that allow it.

On hosts

Signing in and out are This Mac only. A host pulls with its own credentials, signed in on that Mac, and the admin never sends a password over the fleet connection. A host that needs a private image must be signed in to that registry itself.

Default registry

Set as Default chooses where Flotilla's Pull form completes a name that has no registry. With GHCR as the default, owner/app in the Pull form means ghcr.io/owner/app.

It changes only Flotilla's Pull form. It does not change what container resolves a bare name to in Terminal, or in a run command, which is always Docker Hub. That is why the two defaults are two badges: one badge for both would claim the setting changes the runtime.

Browse Docker Hub

Images ▸ Browse Docker Hub… searches Docker Hub inside Flotilla. Opening it lists the Docker Official Images; typing searches. Choose an image to see its tags, newest first, then Pull….

• It never pulls by itself. Pull opens the ordinary Pull form with the reference filled in, and the form checks and runs it exactly as if you had typed it. A search result is untrusted text, not a command.
• Listings that are not images on docker.io — Docker Hardened Images, MCP servers, Docker Desktop extensions and plugins — are labelled as such and cannot be pulled.
• Docker Hub only. If your default is another registry, the page says that registry has no public search, and that pulls from here come from Docker Hub. For other registries, the Pull form's link opens the registry's own website where it has one.
• It asks hub.docker.com only when you open the page or type, and sends only what you typed, with no cookies, no cache and nothing about this Mac.

There is no Docker Hub sign-in in the browser. Sign in from Registries, which signs container in.