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Mutators

Overview

The Mutators section allows you to create reusable values in your mode configuration and link them to CLI flags. This provides a clean way to change configuration values via the command line without editing the YAML directly.

Mutators use YAML anchors and references, which also makes your config DRY (Don’t Repeat Yourself) and easy to maintain.

Example

component_name: *component_name_mutator YourComponentName # assign a mutant

cli_flags: 
  component_name: *component_name_mutator # assign a CLI flag linked to the mutator

component_name: *component_name_mutator # reference the mutator as a key value

How it works

  1. Define a mutator using *mutator_name syntax.
  2. Optionally assign a CLI flag in cli_flags and link it to the mutator.
  3. Reference the mutator anywhere in the mode to reuse its value.

Guidelines

  • Naming convention: it’s recommended to name mutators like keyName_mutator for clarity, though any valid YAML name works.
  • Mutators are optional but highly useful for keeping large configs clean.
  • You can use mutators like regular YAML anchors, not only for CLI flags, to avoid repeating values.

Usage

  • When a CLI flag linked to a mutator is used, ForgeFoundary overrides the value in the configuration dynamically.
  • This makes it easy to customize a scaffolding run without touching your YAML file.