How to specify template for Glimmer Component?

I have a typical Glimmer "base" component:

import Component from '@glimmer/component';
export default class BaseComponent extends Component { ... }

It has a template like normally, but the actual implementations of that component are child componenents, that override some of the template getters and parameters so that it works with various different data types.

export default class TypeAComponent extends BaseComponent { ... }

export default class TypeBComponent extends BaseComponent { ... }

etc.

My question is: How do I specify that all the child components should use the parent class template, so I don't have to duplicate the same fairly complex HTML for all child components? Visually the components are supposed to look identical so any changes would have to be replicated across all child component types. Therefore multiple duplicated templates isn't ideal.

In Ember Classic components there was layout and layoutName properties so I could just do:

layoutName: 'components/component-name'

in the base component and all child components did automatically use the defined template.

Now that I'm migrating to Glimmer components I can't seem to figure out how to do this. I have tried:

• layout property
• layoutName property
• template property
• Using the child components without a template in hope that they would automatically fall back to the parent class template.

Only thing that seems to work is creating Application Initializer like this:

app.register('template:components/child1-component', app.lookup('template:components/base-component'));
app.register('template:components/child2-component', app.lookup('template:components/base-component'));

But that feels so hacky that I decided to ask here first if there is a proper way to do this that I have missed?