# `mix letterbox.gen.migration`
[🔗](https://github.com/hattoriai/letterbox/blob/v0.1.0-rc.0/lib/mix/tasks/letterbox.gen.migration.ex#L1)

Generates the migration of Letterbox's table in the app's repo: the one
that installs it, or, after an upgrade of Letterbox, the one that brings
it to its latest version.

    $ mix letterbox.gen.migration
    $ mix letterbox.gen.migration --repo MyApp.Repo

It is `mix phoenix_mountable.gen.migration Letterbox.Migrations`: the
version the app is at is read from its migrations, and the new migration
pins the latest (see `Letterbox.Migrations`). Run it with `mix
ecto.migrate`.

The options are those of `mix phoenix_mountable.gen.migration`, such as
`--repo` and `--migrations-path`.

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*Consult [api-reference.md](api-reference.md) for complete listing*