# DependencyRequirements

Extracts the services needed to acquire a matcher Layer dependency.

## Signatures

```ts
export type DependencyRequirements<D> = D extends Layer.Layer<any, any, infer R> ? R : never;
```

## Why

Local providers do not hide their own upstream requirements.

## Ownership and lifetime

Computed only by TypeScript; runtime service lifetimes remain those of the environment used to acquire the represented Layer.