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Mend

Try a preview

A preview is a next build: Mend from main, published before the release it leads to. Its version reads like 0.36.0-next.56. It passed the same packaged acceptance as a release; it has not been used for long, and it can change before the release.

Before you install

Section titled “Before you install”
  • A server moves forward only. mend server upgrade refuses a lower version, because database migrations do not run backwards. A server on 0.36.0-next.56 can take a later next build or 0.36.0, never 0.35.1 or 0.36.0-next.50.
  • A patch release may be behind you. A preview of the next minor (0.37.0-next.4) is higher than a patch released after it (0.36.1), so a server on it skips that patch and waits for 0.37.0. Previews of a patch (0.36.1-next.2) lead to the patch.
  • Use a server you can rebuild, or back up its Docker volumes first. The upgrade’s SQL dump does not cover repositories, session captures or SSH identity.
  • Everything else is the same. A preview server is set up, operated and upgraded with the commands in Install Mend.

Install a preview

Section titled “Install a preview”
Terminal window
npm install --global @sealant/mend@next
mend version

mend version prints the version npm installed. Then, on the server machine:

Terminal window
mend server setup

Setup installs the server at the CLI’s version: ghcr.io/sealant-sh/mend:<version> and the setup assets of the GitHub prerelease v<version>. The image carries the Sealant runtime that version pins, which may itself be a prerelease.

Clients on other devices install the same CLI with the same npm install line. When a client and its server differ, mend version says versions differ — the server's API wins; keep them on the same version.

Move to a later preview

Section titled “Move to a later preview”
Terminal window
npm install --global @sealant/mend@next
mend server upgrade --version "$(npm view @sealant/mend@next version)"

The upgrade backs up the databases, stops Mend’s writers and starts the new version, as it does for a release.

A server on a preview numbered before the next channel (0.36.0-preview.K) sorts above every next build of its version, so a plain upgrade refuses it as a downgrade. Add --from-preview once: it moves the server to a next build of the same version, after checking that the target carries every migration the server applied.

Move to the release

Section titled “Move to the release”

When the release ships:

Terminal window
npm install --global @sealant/mend@latest
mend server upgrade --version latest

--version latest resolves the newest release, never a preview, and a release is higher than every preview of it. After that the server follows releases until you install @next again.

If a preview is withdrawn

Section titled “If a preview is withdrawn”

A preview found broken after publishing is deprecated on npm, and next is moved back, so npm install @sealant/mend@next installs the previous one again. A server already on the withdrawn version cannot go back: upgrade to the next preview that replaces it. Its GitHub prerelease says which one.

Report what you find

Section titled “Report what you find”

mend doctor --bundle writes one redacted diagnostic archive. Attach it to an issue at github.com/sealant-sh/mend with the version from mend version. Read Troubleshooting.