Apply Mixins to a Type

A Mixin is a reusable bundle of properties you attach to several Types without making them related. Say you rate Books and Restaurants. Neither is a kind of the other, but both can carry a Rateable Mixin with a rating property, and one query then finds every highly rated thing in your workspace, whatever its Type.

The built-in Taskable Mixin works the same way: it supplies done, due, and recurrence. The built-in Task Type uses it, and you can attach it to a Project or any other custom Type to make it task-like. Then mixin:Taskable prop.due:<2026-08-01 lists everything due before 1 August 2026, Tasks and Projects alike.

Mixins supply properties only. To connect Objects, add a relation to the Type itself.

Create a Mixin

1. Open the command palette and run Open Schema library (Mixins).
2. Select + new mixin.
3. In Define a mixin, enter a Name, such as Rateable.
4. Choose + add property for each property. Give it a name and a Property type; for Rateable, add rating with type number.
5. Select Create.

To edit an existing Mixin’s properties later, select it in the Schema library.

Apply a Mixin to a Type

1. Open Object type settings → Mixins.
2. Choose + Add mixin and pick the Mixin.

The Mixin’s card lists the properties it contributes. You can also attach Mixins on the Mixins step when creating a Type.

Try it: rate across Types

Apply Rateable to your Book and Restaurant Types, rate a few of each, then search for mixin:Rateable prop.rating:>=4. The results mix Books and Restaurants, because the query asks about the shared property rather than a Type. See Query language.

Resolve name conflicts

Lar never lets two properties with the same name silently shadow each other, so it refuses to apply a Mixin that would collide. The Mixin picker marks such a Mixin with “name” already exists. A collision happens when a Mixin property has the same name as:

• a property the Type defines itself;
• a property inherited from the parent Type; or
• a property from another Mixin on the same Type.

For example, the Book preset in the Type gallery has its own rating label property, so a preset-based Book can’t take Rateable as-is. Rename one of the two properties, or pick a Type that doesn’t already define rating.

Remove a Mixin

In Object type settings → Mixins, choose Remove on the Mixin’s card and confirm with Remove mixin.

Caution

Removing a Mixin clears its properties’ values on every Object of the Type and its subtypes. It can’t be undone. Check saved queries, views, templates, and workflows that use those properties first.

Mixin, inheritance, or relation?

Use	When the answer is	Example
Inheritance	”X is a Y”	An Employee is a Person
Mixin	”X has this capability”	Books and Restaurants are Rateable
Relation	”X is connected to Y”	A Book has an author, who is a Person

A Type has one parent and can have any number of Mixins.

Mixins also keep values safe when you change an Object’s Type: if both Types carry Rateable, the rating carries over unchanged.

Next: Relations and backlinks.