Name: TCA Feature Development
Author: ninjaproger

Workflow

Explore first — read the target module and its neighbours before writing anything
Create the reducer — see references/feature-template.md
Create the view — see references/view-patterns.md
Add previews — one per meaningful state; see Preview Rules below
Write tests — see references/testing-patterns.md
Register — add target to Package.swift; wire into parent if it's a new tab

Explore Before Writing

Before implementing any feature, read:

Explore first — read the target module and its neighbours before writing anything
Create the reducer — see references/feature-template.md
Create the view — see references/view-patterns.md
Add previews — one per meaningful state; see Preview Rules below
Write tests — see references/testing-patterns.md
Register — add target to Package.swift; wire into parent if it's a new tab

Before implementing any feature, read:

Question	Answer
Reducer + View in one file?	Yes, when combined ≤ ~200 lines
Where do computed properties go?	On `State`, not the view
How to pass data to a child feature?	Initialize child's `State` when setting `destination`
How to communicate upward?	`.delegate(Delegate)` action
Where does error text live?	`state.loadError: String?` via `error.localizedDescription`
How to cancel in-flight effects?	`.cancellable(id:, cancelInFlight: true)`
Where do sub-view components live?	File-private structs in the same `.swift` file
Should I use `UIViewRepresentable`?	Only when SwiftUI has no equivalent (e.g. `MKMapView`, `WKWebView`). Never for styling convenience.
Which concurrency primitive?	`async/await` + `AsyncStream` first; Combine only if the API has no async alternative; GCD/NSLock only for legacy C/ObjC callbacks