NgRx v22 wraps Angular's resource so value() stops vanishing on reload and throwing on error

The version of this most teams already have is a `computed()` that holds the last defined value, plus a status check wrapped around every read. It works, and it hands back a Signal, so anything downstream that wanted the resource itself has to be given the original as well. `extendResource` returns the exact resource that went in, with access to more specific types such as `WritableResource` preserved ^[5], and only `value()` behaves differently ^[10]. That is the part that justifies the edit: there is no second object to keep in sync with the first.

The four built-ins are a two-by-two ^[7]. Two moments when `value()` is not what you want, loading and error, and two answers for each: the last resolved value, or a fallback you name [c7d].

Because only `value()` is patched, `error()` and `status()` still report what happened [c10d]. That is worth being deliberate about. With `withValueOnError(undefined)` applied, the read that used to throw now returns a value ^[6], so any code path that let the throw do the signalling needs an explicit check instead. The NgRx announcement's stated case for `withPreviousValueOnLoading` is paginated and filtered lists that flicker while a reload is in flight ^[12], and that is the one where the change stays invisible to everything around it.

The scoping reads better than it deploys. `provideResourceExtensions` registers extensions for an injector scope, application, route or component, and composes with what parent injectors registered ^[8], so a default set at bootstrap can be refined further down. But extensions still arrive through the wrapper: with globals in place, passing the resource alone to `extendResource` is enough ^[9]. A resource created by a bare `httpResource()` call and never passed through `extendResource` keeps Angular's original behaviour [c9d]. One provider at bootstrap does not change how an existing codebase behaves; it changes what each call site gets once someone has edited that call site. The work is priced per resource, not per application.

Set against that, the entry point is marked experimental ^[11]. Deleting a hand-written cache in its favour swaps code you control for an API whose signatures can still move, and the failure mode of a moved signature is a compile error rather than a silent behaviour change, which is the cheaper of the two.

The same release does the equivalent tidying for state shapes: a union slice used to collapse into a single flat `Signal`, and now each object-literal member of the union gets its own `DeepSignal` ^[13]. Both changes take away glue code rather than add surface, which is a more useful thing for a major version to do than it sounds.