Installation

npm install forty-cdk

The package is unscoped, so pnpm add forty-cdk and yarn add forty-cdk are the same install.

Nothing else is required to render your first primitive. The packages forty-cdk needs internally (@floating-ui/dom for overlay positioning, @tanstack/virtual-core for virtualization) are regular dependencies installed with it, and they are tree-shaken out of bundles that import no overlay and no virtualized list.

Two peers are required, and every other one is optional and unlocks a specific part of the library.

An optional peer you have not installed costs you nothing. Nothing outside the entry point that needs it imports it by value, so a bundle that never touches Signal Forms never resolves @angular/forms.

If you are choosing a date adapter, the Date adapters guide is the page that answers which one to provide.

forty-cdk itself exports nothing. This is deliberate, and it is the one thing about the package that surprises people:

import { ForDialog } from 'forty-cdk';

That import resolves to an empty barrel and fails to compile. Every primitive is imported from its own entry point instead:

import { ForDialog, ForDialogTitle, ForDialogTrigger } from 'forty-cdk/dialog';
import { ForSwitch } from 'forty-cdk/switch';

The entry point is the primitive's folder name, lower-kebab: forty-cdk/date-picker, forty-cdk/dropdown-menu, forty-cdk/hover-card. Each page on this site states its own import line under Anatomy.

The reason is bundle size. Each entry point builds to a module of its own, so importing ForSwitch gives your bundler a file it can resolve without ever seeing Dialog, Table or Calendar. A single root barrel re-exporting every entry point would put them all on one module graph and make that isolation a tree-shaker's problem rather than a structural fact. Leaving the root empty is what removes the question (see why the root barrel is empty).

Two entry points are shared rather than per-primitive:

• forty-cdk/shared: the cross-primitive contracts a consumer meets in more than one place, and the accessibility limits that apply library-wide.
• forty-cdk/internationalized-date: the @internationalized/date calendar adapters, kept apart so only consumers who provide one need that peer.

forty-cdk targets Angular 22 and above, and tracks the latest minor rather than supporting a range of majors. The library is pre-1.0, so a breaking change can land in a minor release. Pin the version you build against and read the changelog before upgrading.

Two application-level requirements are worth stating, because both are properties of the library rather than settings you turn on:

• Zoneless is supported, and Zone.js is never required. Every primitive works under provideZonelessChangeDetection(); none of them import NgZone. If your application still runs with Zone.js, nothing here changes.
• Server-side rendering is safe by default. No primitive touches document or window outside a browser-only branch, and every one of them is covered by a server-render smoke test.

• Getting started: from this install to a working, styled primitive.
• Concepts: the composition model, data-* state and the entry-point layout.
• Styling forty-cdk: the three hooks you write CSS against.