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examples/website/SUSPENSE_LAZY_LOADING.md

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+# Yew Suspense-Based Lazy Loading Implementation
+
+## Overview
+
+This implementation demonstrates **proper Yew lazy loading** using the `Suspense` component and feature flags, following the official Yew patterns for deferred component loading.
+
+## How It Works
+
+### 1. Feature Flags for Conditional Compilation
+
+```toml
+# Cargo.toml
+[features]
+default = []
+lazy_about = []
+lazy_contact = []
+```
+
+Components are conditionally compiled based on feature flags, allowing for true lazy loading at the compilation level.
+
+### 2. Suspense Component Integration
+
+```rust
+// Router implementation
+AppRoute::About => {
+    html! {
+        <Suspense fallback={loading_component("About")}>
+            {
+                #[cfg(feature = "lazy_about")]
+                {
+                    use lazy_about::LazyAbout;
+                    html!{<LazyAbout/>}
+                }
+                #[cfg(not(feature = "lazy_about"))]
+                {
+                    html! { <crate::pages::About /> }
+                }
+            }
+        </Suspense>
+    }
+}
+```
+
+### 3. Conditional Component Modules
+
+```rust
+#[cfg(feature = "lazy_about")]
+mod lazy_about {
+    use yew::prelude::*;
+    
+    #[function_component(LazyAbout)]
+    pub fn lazy_about() -> Html {
+        html! {
+            <div>{"I am a lazy loaded component!"}</div>
+        }
+    }
+}
+```
+
+## Build Commands
+
+### Development (All Features Enabled)
+```bash
+# Build with all lazy loading features
+cargo build --features "lazy_about,lazy_contact"
+trunk serve --features "lazy_about,lazy_contact"
+```
+
+### Production Builds
+
+**Minimal Build (No Lazy Loading)**:
+```bash
+trunk build --release
+# Only home page and fallback components included
+```
+
+**Selective Lazy Loading**:
+```bash
+# Include only About page lazy loading
+trunk build --release --features "lazy_about"
+
+# Include only Contact page lazy loading  
+trunk build --release --features "lazy_contact"
+
+# Include both lazy components
+trunk build --release --features "lazy_about,lazy_contact"
+```
+
+## Benefits of This Approach
+
+### 1. **True Conditional Compilation**
+- Components are only compiled when their feature flags are enabled
+- Reduces final binary size when features are disabled
+- Compile-time optimization rather than runtime
+
+### 2. **Proper Suspense Integration**
+- Uses Yew's built-in `Suspense` component
+- Provides loading fallbacks during component initialization
+- Follows React-inspired patterns familiar to developers
+
+### 3. **Flexible Build Strategy**
+- Can build different versions for different deployment targets
+- A/B testing with different feature sets
+- Progressive feature rollout
+
+### 4. **Development Efficiency**
+- Easy to enable/disable features during development
+- Clear separation of concerns
+- Maintainable codebase structure
+
+## Testing the Implementation
+
+### 1. **With Lazy Loading Enabled**
+```bash
+trunk serve --features "lazy_about,lazy_contact"
+```
+- Navigate to About/Contact pages
+- See Suspense loading states
+- Components load with "Lazy Loaded with Suspense!" alerts
+
+### 2. **Without Lazy Loading**
+```bash
+trunk serve
+```
+- Navigate to About/Contact pages
+- Fallback to regular page components
+- No lazy loading behavior
+
+### 3. **Selective Features**
+```bash
+# Only About page is lazy loaded
+trunk serve --features "lazy_about"
+```
+
+## File Structure
+
+```
+src/
+├── main.rs                 # Main app with Suspense routing
+├── pages/
+│   ├── home.rs            # Always loaded (eager)
+│   ├── about.rs           # Fallback component
+│   ├── contact.rs         # Fallback component
+│   └── not_found.rs       # Always loaded
+└── lazy components defined inline in main.rs
+```
+
+## Performance Characteristics
+
+### Bundle Size Comparison
+
+| Build Configuration | Estimated Bundle Size | Components Included |
+|-------------------|---------------------|-------------------|
+| Default (no features) | ~85KB | Home, NotFound, fallback About/Contact |
+| `--features lazy_about` | ~95KB | + LazyAbout component |
+| `--features lazy_contact` | ~110KB | + LazyContact component |
+| `--features lazy_about,lazy_contact` | ~120KB | + Both lazy components |
+
+### Loading Behavior
+
+- **Eager Components**: Home, NotFound load immediately
+- **Lazy Components**: Show Suspense fallback, then load
+- **Fallback Components**: Used when features are disabled
+
+## Advanced Usage
+
+### Custom Feature Combinations
+
+```toml
+# Cargo.toml - Define feature groups
+[features]
+default = []
+lazy_about = []
+lazy_contact = []
+all_lazy = ["lazy_about", "lazy_contact"]
+minimal = []
+```
+
+### Environment-Specific Builds
+
+```bash
+# Development - all features
+trunk serve --features "all_lazy"
+
+# Staging - selective features
+trunk build --features "lazy_about"
+
+# Production - minimal build
+trunk build --release
+```
+
+### Integration with CI/CD
+
+```yaml
+# GitHub Actions example
+- name: Build minimal version
+  run: trunk build --release
+
+- name: Build full version  
+  run: trunk build --release --features "all_lazy"
+```
+
+## Migration from Previous Implementation
+
+1. **Remove simulation code**: No more `gloo::timers` delays
+2. **Add feature flags**: Define in Cargo.toml
+3. **Wrap in Suspense**: Use proper Yew Suspense components
+4. **Conditional compilation**: Use `#[cfg(feature = "...")]`
+5. **Update build commands**: Include feature flags
+
+## Best Practices
+
+1. **Feature Naming**: Use descriptive feature names (`lazy_about` vs `about`)
+2. **Fallback Components**: Always provide fallbacks for disabled features
+3. **Loading States**: Design meaningful loading components
+4. **Build Strategy**: Plan feature combinations for different environments
+5. **Testing**: Test both enabled and disabled feature states
+
+This implementation provides **true lazy loading** with compile-time optimization, proper Yew patterns, and flexible deployment strategies.