[crazy-max]

• closes Migrate from github.com/docker/docker to github.com/moby/moby/client (v29 module path change) #3792
• supersedes and closes store: remove uses of docker namesgenerator #3354
• supersedes and closes store: replace namesgenerator with neutral builder IDs #3813

This removes the remaining github.com/docker/docker dependency by replacing its pkg/namesgenerator package with golang-petname. Buildx has already migrated its client and API dependencies to the Moby modules, but generating random builder names still keeps the deprecated Docker module in its dependency graph and those of downstream consumers. The daemon CVEs reported in #3792 do not affect the naming code Buildx imports, as explained in #3792 (comment). This is dependency cleanup rather than a fix for a demonstrated Buildx vulnerability.

The change preserves memorable, two-word names and the existing underscore separator, using adjectives and animal-oriented names instead of notable people's surnames. Existing builders and explicitly supplied names are unaffected, and generation still makes up to six attempts to find an unused name in the local store. This retains names that are convenient to recognize, remember, and type without maintaining Buildx-specific word lists as proposed in #3354 or switching to opaque identifiers as proposed in #3813.

The generation logic itself is small. The reason for using an external module is to avoid taking ownership of another generator and its vocabulary, which was also a concern raised in #3354 (comment). Petname provides a small API and implementation, supports the existing separator directly, and has no external module dependencies. The selected word lists contain only lowercase ASCII letters, so generated names need no additional sanitization.

I compared several standalone Go generators and initially implemented fname. Its broader vocabulary provides more combinations, but I ultimately preferred petname's smaller implementation, dependency-free module, and established use in projects such as Terraform's random provider, LXD and PhotoPrism.

The pinned petname version provides 448 adjectives and 448 names, giving 200,704 two-word combinations. That compares with 25,487 initial combinations in the legacy Docker generator, excluding its numeric retry suffixes. This increases the initial name space without adding a third word or a mandatory numeric suffix.

Petname could also be evaluated independently by Moby as an optional name-generator extension alongside the discussion in moby/moby#52097. That would allow reuse of the same standalone library without duplicating word lists, but this PR does not depend on Moby adopting it or changing its default naming scheme.

AI-assisted with Codex for researching name-generator alternatives, implementing the change, and running validation. Claude Code provided an independent review.

[thaJeztah]

do we really need a new dependency for this? Old code was ... 10 lines or so?

[crazy-max]

Yes the generation logic is small, agreed. What I'd like to avoid is maintaining another generator and its word lists ourselves, which was also a concern raised in #3354. That's why I went with a standalone external module rather than copying the implementation into Buildx. I'm not particularly attached to fname though, so if you have another lightweight module in mind, I'm open to it.

[crazy-max]

I've switched this to golang-petname. It's smaller, has no external dependencies, and is already used by big projects like Terraform's random provider.