Built-in types

Updated Oct 19, 2026 v0.0.1

Gervaz resolves a type name in the DSL to a module. This page lists the built-in column, filter, action and field types, and the ui.extra keys each column type reads. A module that implements the matching behaviour also works as a column type or an action type, with no registration. A custom filter or field module is used only to parse, validate and query. Gervaz returns a name it does not know unchanged, so a misspelled ui do type :imagee end does not fail at compile time. The schema also accepts :currency, :percentage, :time, :image, :avatar, :progress, :json and :custom as column types. No module draws them, so they raise when the cell is drawn. To write your own, see Write a custom type.

Column types

Set a column type with ui do type :badge end. A column without a type takes one from its Ash attribute when the attribute type is in the last column of this table, and :text otherwise.

Type	Draws	Inferred from
`:text`	Plain text, with optional truncation. The default.	anything else
`:boolean`	A check or a cross icon, or a text label.	`Ash.Type.Boolean`
`:number`	A number with optional prefix, suffix and separators.	`Ash.Type.Integer`, `Ash.Type.Float`, `Ash.Type.Decimal`
`:date`	A date in a format you choose.	`Ash.Type.Date`
`:datetime`	A date and time in a format you choose, or a relative time.	`Ash.Type.DateTime`, `Ash.Type.UtcDatetime`, `Ash.Type.UtcDatetimeUsec`
`:uuid`	A UUID cut to its first characters.	`Ash.Type.UUID`, `Ash.Type.UUIDv7`
`:array`	The items of a list, joined or drawn as badges.	array attributes
`:badge`	A status badge whose color and label come from the value.	never inferred
`:bars`	A small numeric value as filled bars beside the number.	never inferred
`:tags`	A list value as chips, with a `+N` chip that expands the rest in place.	never inferred
`:avatars`	Related people as an overlapping avatar stack, with a `+N` disc that expands the rest.	never inferred
`:link`	A clickable link.	never inferred

Options in ui.extra

Each type reads its options from the extra map of the column's ui block.

Type	Key	Meaning
`:text`	`:max_length`	Truncates the text after this many characters. Not set by default.
`:text`	`:truncate_suffix`	The suffix of truncated text. Default `"..."`.
`:text`	`:dir`	`"ltr"`, `"rtl"` or `"auto"`. Without it, a value of printable ASCII with no space, such as an email, a URL or an ID, reads left to right, and any other value follows the page.
`:boolean`	`:true_icon`, `:false_icon`	The icons. Defaults `"hero-check"` and `"hero-x-mark"`.
`:boolean`	`:true_class`, `:false_class`	The icon classes. The UI adapter supplies the defaults, which are `"size-5 text-[#177a53]"` and `"size-5 text-[#c0473d]"` in the Tailwind adapter. A value you set replaces the whole string, `size-5` included.
`:boolean`	`:true_label`, `:false_label`	Text labels, as an alternative to the icons.
`:number`	`:precision`	Decimal precision. It applies to floats and decimals, and integers ignore it. Not set by default, so the number shows as it is.
`:number`	`:prefix`, `:suffix`	Strings placed before and after the number, such as `"$"` or `" kg"`.
`:number`	`:thousands_separator`, `:decimal_separator`	Separators. Defaults `","` and `"."`.
`:date`	`:format`	A date format string. Default `"%Y-%m-%d"`.
`:datetime`	`:format`	A format string. Default `"%Y-%m-%d %H:%M"`.
`:datetime`	`:relative`	Shows a relative time such as "2 hours ago". Default `false`.
`:uuid`	`:show_full`	Shows the whole UUID. Default `false`.
`:uuid`	`:prefix_length`, `:suffix_length`	Characters shown at the start and the end. Defaults `8` and `0`.
`:array`	`:separator`	The separator between items. Default `", "`.
`:array`	`:max_items`	The most items to show. Not set by default, so all show.
`:array`	`:as_badges`, `:badge_class`	Draws each item as a badge, and the badge class. Default `false`.
`:badge`	`:colors`	A map of value to color class. Keys match the string form of the value first, then its existing atom.
`:badge`	`:labels`	A map of value to label, translated in the reader's locale. A value without one falls back to its humanized form.
`:badge`	`:dots`	A map of value to dot class, for the `:pill` variant.
`:badge`	`:variant`	`:tag` (the default) or `:pill`, which has a leading dot.
`:badge`	`:default_color`	The color class for a value that is not in `:colors`.
`:bars`	`:max`	The number of bars. Default `4`.
`:bars`	`:percent`	Set `true` when the value is a 0 to 100 weight. The bars fill in proportion, and the color follows the percentage band.
`:bars`	`:ceiling`	An explicit denominator for proportional fill. `percent: true` is shorthand for `ceiling: 100`. Without either, the lit count is `min(max, value + 1)`.
`:bars`	`:scale`	An ordered list of `{max_value_inclusive, hex}` tuples ending in `{:default, hex}`. The first entry whose threshold is at least the value wins.
`:tags`	`:max_items`	Chips shown before the `+N` chip. Default `2`.
`:tags`	`:badge_class`, `:empty`	The chip class, and the text for an empty list. An item is a string, or `%{label:, class:, title:}` for a chip styled on its own.
`:avatars`	`:max_items`	Faces shown before the `+N` disc. Default `3`.
`:avatars`	`:image_field`, `:label_field`	The fields of the related record that hold the image URL and the name. Defaults `:avatar_url` and `:name`.
`:avatars`	`:tints`, `:size`, `:empty`	Disc classes cycled by position for entries with no image, the disc size class (default `"size-[26px]"`), and the text for an empty list.
`:link`	`:path_fn`	A function of the record that returns the path. Needed for navigation.
`:link`	`:external`	Opens the link in a new tab. Default `false`.
`:link`	`:class`, `:label_fn`	The link class, and a function that returns the label. Without a label function the column value is the label.

Filter types

Set a filter type as the second argument: filter :status, :select. A filter without a type is a :text filter.

Type	Draws
`:text`	A text input. It matches part of a value without regard to case. A `%` or `_` in the term is that character. The `fields` option searches several fields at once.
`:select`	A dropdown. Options come from `options`.
`:boolean`	A checkbox.
`:number`	The built-in table template draws it as a plain text input. `Filter.Number.render_input/3` exists, and the template does not call it.
`:date`	The built-in table template draws it as a plain text input.
`:date_range`	Two date inputs. Use `source` when the field has another name.
`:relation`	A select over related records. `mode` sets how the options load. With `options` and no resource, it is a searchable list the database does not hold as rows, and its values are strings.

Action types

Set an action type with the type option of a row action. A bulk action accepts only :event, :destroy, :update, :unarchive and :permanent_destroy, and no custom module. :link, :edit, :row_click and :accordion are for row actions only.

Type	Draws or does
`:link`	A navigation link to `path`, which is a string used as written or a function of the record. An action named `:show` or `:show_link` goes to `{route}/{id}`, and one named `:edit` or `:edit_link` to `{route}/{id}/edit`, even when a string `path` is set. Only a function `path` takes precedence over the name. A `:link` action with no `path` is reported when you compile.
`:event`	A button that fires an event. The default. The payload is `%{id: record.id}` unless you set `payload`.
`:edit`	A button that sends the record to the form component, which reads it again even when it is already open. A `js` function runs first, so it can open a modal.
`:destroy`	A delete button with confirmation.
`:update`	A button that runs an Ash update action, named by `action`.
`:unarchive`	A restore button for archived records.
`:permanent_destroy`	A button that permanently deletes an archived record.
`:row_click`	Declares a clickable row, by `path` or `event`. It draws nothing, and the built-in templates do not call its click handler.
`:accordion`	An expand and collapse toggle. It draws nothing unless the `:expand` feature is on. It sends `{:expand_row, id}` to the parent LiveView, which answers with `expanded_html`.

The schema also lists :modal as a row action type, but the built-in registry has no entry for it.

Field types

Set a field type as the second argument: field :body, :textarea. A field without a type takes one from its Ash attribute, as the table on Form fields DSL shows.

Type	Draws
`:text`	The default text input. It strips HTML tags and trims whitespace. The input follows what is typed. Set `ui do extra %{dir: "ltr"} end` for a value always written left to right.
`:password`	A masked input. It trims only the surrounding whitespace.
`:textarea`	A multi-line input. It keeps newlines and markup.
`:number`	A numeric input. It checks that the value is a number. The field options `min` and `max` and `ui step` are accepted, and the Standard form template does not pass them to the input.
`:checkbox`	A checkbox.
`:toggle`	A boolean switch.
`:date`	A date picker. It checks for an ISO 8601 date.
`:datetime`	A date and time picker. It accepts ISO 8601 values, and the minutes-only value a browser sends.
`:range`	A range slider from 0 to 100 in steps of 1. The options `min`, `max` and `ui step` do not change it.
`:select`	A single-select dropdown. An empty choice comes before the options, labeled with `ui placeholder` when you set one and "Select..." otherwise. A required field or one with a `default` has no empty choice.
`:multi_select`	A multi-select dropdown.
`:combobox`	A text input with a list of suggestions. The reader can type any value. The options load once, when the form starts.
`:relation`	A picker for related records, in the four modes of `mode`.
`:json`	A JSON editor. It decodes JSON strings and checks that the value is valid JSON.
`:key_map`	A map whose keys you declare, drawn as one control per key.
`:key_list`	A list of maps whose keys you declare, with rows the reader adds and removes.
`:nested`	An embedded form for an embedded resource or a constrained map attribute, built from `nested_field` entities.
`:array_of_maps`	The schema accepts it, and the Standard form template draws it as a plain text input. Use `:nested` or `:key_list` for repeatable groups.
`:string_list`	A list of text inputs with add and remove buttons, for `{:array, :string}` attributes. It drops empty strings.
`:file`	A file input.
`:upload`	A position for an upload declared in the `uploads` section. Gervaz marks such a field virtual.
`:hidden`	A hidden input.