Reservoir Reference

Overview

Reservoir is the Mississippi client-state management subsystem.

Applies To

• Mississippi.Reservoir.Abstractions
• Mississippi.Reservoir.Core
• Mississippi.Reservoir.Client
• Mississippi.Reservoir.TestHarness

Public Registration Entry Points

Entry point	Receiver	Returns	Purpose
AddReservoir()	IServiceCollection	IReservoirBuilder	Create the top-level Reservoir builder from DI
AddReservoir()	WebAssemblyHostBuilder	IReservoirBuilder	Create the same builder from Blazor WebAssembly startup

Source code:

• ReservoirRegistrations.cs
• ReservoirWebAssemblyHostBuilderRegistrations.cs

IReservoirBuilder

IReservoirBuilder is the top-level public registration contract.

Member	Purpose
Services	Advanced access to the underlying IServiceCollection
AddFeatureState<TState>()	Register a feature state without extra reducers or effects
AddFeatureState<TState>(configure)	Register a feature state and configure reducers or effects in one callback
AddMiddleware<TMiddleware>()	Add middleware to the Reservoir dispatch pipeline

The Services property is marked advanced in the public contract. The normal direction is to compose through builder extension methods instead of writing more direct service registrations in application startup.

IReservoirFeatureBuilder

IReservoirFeatureBuilder<TState> is the feature-scoped public contract used inside AddFeatureState<TState>(configure).

Its staged service collection is writable during that callback and becomes read-only when the callback exits, including on failure. Complete feature registration inside the callback; retaining the feature builder does not extend its configuration lifetime.

Configure the supplied feature builder inside the callback. Add other feature states and middleware through the root before or after it; reentrant root registration is rejected before it runs. Direct parent-service changes reject the feature commit instead of being overwritten, preserving those changes while the failed feature scope closes.

Accessing the root builder's Services inside a feature callback also throws before returning the collection. This protects composite extensions, such as AddInletClient(), from partially registering parent services before a later root operation is rejected. Use the supplied feature builder's services for advanced feature configuration.

Member	Purpose
Services	Advanced access to the underlying IServiceCollection
AddActionEffect<TEffect>()	Register a feature-scoped action effect
AddReducer<TAction>(Func<TState, TAction, TState> reduce)	Register a reducer delegate
AddReducer<TAction, TReducer>()	Register a reducer implementation type

Source code:

• IReservoirBuilder.cs
• IReservoirFeatureBuilder.cs

Verified Client Builder Extensions

The current client-side extensions that build on IReservoirBuilder are:

Method	Package	Purpose
AddReservoirBlazorBuiltIns()	Mississippi.Reservoir.Client	Register both built-in navigation and lifecycle features
AddBuiltInNavigation()	Mississippi.Reservoir.Client	Register the navigation feature only
AddBuiltInLifecycle()	Mississippi.Reservoir.Client	Register the lifecycle feature only
AddReservoirDevTools(...)	Mississippi.Reservoir.Client	Register Redux DevTools integration

Source code:

• ReservoirBlazorBuiltInRegistrations.cs
• NavigationFeatureRegistration.cs
• LifecycleFeatureRegistration.cs
• ReservoirDevToolsRegistrations.cs

Verified Ownership Boundary

• Store and dispatch pipeline abstractions
• Feature state, actions, reducers, selectors, effects, and middleware
• Client integration and testing support for that model
• Public registration builders for top-level and feature-level composition

Related But Separate Areas

• Refraction owns the Blazor UX layer.
• Inlet owns generated full-stack alignment.

Defaults And Constraints

This reference covers the verified subsystem boundary and the current public registration surface. See Archived Reservoir Docs for preserved deep API material that has not yet been rewritten into the active docs set.

Startup Direction

Builder-based composition is the direction of the public Reservoir registration model going forward.

Reservoir-only application startup should begin with AddReservoir() and then compose package or feature extensions on the returned IReservoirBuilder. Full Mississippi client apps should begin with UseMississippi(...) and use client.Reservoir(...) when they need Reservoir-level composition.

Failure Behavior

When the parent service collection is read-only, Reservoir rejects registration before invoking a new feature callback. Attempts to register through a completed parent or feature scope throw InvalidOperationException. In a full Mississippi client, terminal attachment closes the parent collection as described in Client Composition.

For runtime and API-level failure behavior, refer to the Archived Reservoir Docs and the Reservoir Concepts page.

Summary

Use this page as the current active reference for Reservoir's builder entry points, feature-builder contracts, and verified client registration extensions.

Next Steps

• Add a Reservoir feature to define, register, dispatch, and select local state.
• State flow for reducer, notification, and effect timing.
• Selector reference for store selection and memoization.
• Read Reservoir Concepts.
• Read Inlet Reference for the client-sync extensions that compose on top of Reservoir.
• Use Archived Reservoir Docs for preserved deep material.