# `mix ash.codegen`
[🔗](https://github.com/ash-project/ash/blob/v3.23.1/lib/mix/tasks/ash.codegen.ex#L5)

Runs all codegen tasks for any extension on any resource/domain in your application.

## Flags

* `--dry-run` - no files are created, instead the new generated code is printed to the console
* `--check` - no files are created, returns an exit(1) code if any code would need to be generated
* `--dev` - runs codegen tasks in dev mode. See the section on dev mode below
* Individual extensions may use additional flags.

## Dev Mode

Some extensions that do `codegen` require providing a `name`. Those extensions (should) support a `--dev`
flag, which indicates that the codegen can have a temporary name chosen by the extension. Then, once you
are ready to commit the changes, you can run the codegen tasks again without the `--dev` flag and with a
name to generate the final code.

For example, using AshPostgres:

- First we add `first_name` to `MyApp.Accounts.User`
- `mix ash.codegen --dev`, which generates a migration for adding `first_name` to the `"users"` table,
  but the migration is suffixed with `_dev`
- `mix ash.migrate` apply the migrations
- Then we add `last_name` to `MyApp.Accounts.User`
- `mix ash.codegen --dev` which generates a migration for adding `last_name` to the `"users"` table,
  but the migration is suffixed with `_dev`
- We review our changes, and are ready to save them as a unit
- `mix ash.codegen add_name_to_user`, which rolls back and deletes the dev migrations & snapshots, and creates new
  ones using the provided name

# `run`

Runs all codegen tasks for any extension on any resource/domain in your application.

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