Patterns well-covered elsewhere

The following patterns are intentionally not included as controllers on this site because mature, popular open-source implementations already exist. Reach for these instead:

PatternPackage
Toggle / revealstimulus-reveal-controller
Textarea autogrowstimulus-textarea-autogrow
Checkbox select allstimulus-checkbox-select-all
Dropdownstimulus-dropdown
Auto-submit formstimulus-auto-submit
Rails nested formstimulus-rails-nested-form
Autosavestimulus-rails-autosave

For textarea autogrow specifically, also consider the CSS-only field-sizing: content property — no JS needed in browsers that support it (Chrome/Edge 123+, Safari 26.2; in preview in Firefox; as of 2026).

stimulus-use

None of the controllers on this site require a dependency beyond @hotwired/stimulus itself. If a controller benefits from one of the composable behaviors in stimulus-use (debouncing, intersection/visibility, idle detection, and similar), its README notes that as an optional addition — it’s worth knowing about as a general-purpose companion library even outside this site’s controllers.