FAQ

How is Nrgy.js different from a typical state manager?

Nrgy.js is not only about storing and updating state. It combines fine-grained reactivity with explicit lifecycle ownership, controllers, and view models.

The main difference is that it is designed to keep business logic, state, cleanup, and UI contracts separate instead of treating state management as an isolated concern.

Why does effect() not run immediately?

By default, effect() is deferred. This allows several synchronous state updates to settle first, so the effect can observe the final consistent state instead of intermediate values.

If you need synchronous observation, use syncEffect(), but only when the ordering really matters.

When should I use batch()?

Use batch() when several writes form one logical transition and observers should only see the final consistent state.

Typical cases:

• updating several form fields together
• applying server data to several atoms at once
• preventing observers from reacting to intermediate states

Why do I need scope?

Scope is the ownership boundary for reactive resources.

Use it to collect:

• effects and subscriptions
• child scopes
• atoms created for a feature
• custom cleanup callbacks

When the owner is destroyed, scope lets you release everything in one place.

When should I call destroy()?

Call destroy() when the feature that owns the resource is finished.

Typical cases:

• a screen is unmounted
• a temporary flow ends
• a long-lived controller or view model is no longer needed

If a controller, scope, or atom can outlive its usefulness and still stay reachable, it should have an explicit destruction point.

How is MVVM different from MVC here?

In this documentation, the useful difference is practical:

• MVC keeps more explicit coordination and binding logic in the controller
• MVVM emphasizes a cleaner view-facing contract through a view model

Both separate business logic from rendering, but MVVM is the more useful mental model for UI-facing contracts in Nrgy.js.

How should I pass dependencies?

Use params for explicit feature inputs. Use extensions or DI for infrastructure-level dependencies.

Examples of params:

• initial values
• screen identifiers
• feature configuration

Examples of DI:

• API clients
• loggers
• gateways
• analytics services

Can I use Nrgy.js without React?

Yes. The core primitives, controllers, view models, scopes, and DI integrations do not require React.

React is only one UI integration layer. The same business logic can be used in headless flows, SDK-like integrations, tests, or other UI environments.