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skills/refactoring-safely/resources/example-session.md

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+## Example: Complete Refactoring Session
+
+**Goal:** Extract validation logic from UserService
+
+**Time: 60 minutes**
+
+### Minutes 0-5: Verify Tests Pass
+```bash
+Dispatch hyperpowers:test-runner: "Run: cargo test"
+Result: ✓ 234 tests pass
+```
+
+### Minutes 5-10: Create bd Task
+```bash
+bd create "Refactor: Extract user validation" --type task
+bd edit bd-456 --design "Extract validation to UserValidator class..."
+bd update bd-456 --status in_progress
+```
+
+### Minutes 10-15: Step 1 - Extract email validation function
+```rust
+// Extract validate_email()
+```
+```bash
+Dispatch hyperpowers:test-runner: "Run: cargo test"
+Result: ✓ 234 tests pass
+git commit -m "refactor(bd-456): extract email validation"
+```
+
+### Minutes 15-20: Step 2 - Extract name validation function
+```rust
+// Extract validate_name()
+```
+```bash
+Dispatch hyperpowers:test-runner: "Run: cargo test"
+Result: ✓ 234 tests pass
+git commit -m "refactor(bd-456): extract name validation"
+```
+
+### Minutes 20-25: Step 3 - Create UserValidator struct
+```rust
+struct UserValidator { /* empty */ }
+impl UserValidator { /* empty */ }
+```
+```bash
+Dispatch hyperpowers:test-runner: "Run: cargo test"
+Result: ✓ 234 tests pass
+git commit -m "refactor(bd-456): create UserValidator struct"
+```
+
+### Minutes 25-35: Steps 4-6 - Move validations to UserValidator
+Each step: move one method, test, commit
+
+### Minutes 35-45: Step 7 - Update UserService to use validator
+```rust
+// Use UserValidator instead of inline validation
+```
+```bash
+Dispatch hyperpowers:test-runner: "Run: cargo test"
+Result: ✓ 234 tests pass
+git commit -m "refactor(bd-456): use UserValidator in UserService"
+```
+
+### Minutes 45-55: Step 8 - Remove duplication from other services
+Each service: one change, test, commit
+
+### Minutes 55-60: Final verification and close
+```bash
+Dispatch hyperpowers:test-runner: "Run: cargo test"
+Result: ✓ 234 tests pass
+
+Dispatch hyperpowers:test-runner: "Run: cargo clippy"
+Result: ✓ No warnings
+
+bd close bd-456
+```
+
+**Result:** Refactoring complete, 8 safe commits, all tests green throughout.

skills/refactoring-safely/resources/refactoring-patterns.md

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+## Common Refactoring Patterns
+
+### Extract Method
+
+**When:** Duplicated code or long function
+
+```rust
+// Before: Long function
+fn process(data: Vec<i32>) -> i32 {
+    let mut sum = 0;
+    for x in data {
+        sum += x * x;
+    }
+    sum
+}
+
+// After: Extracted method
+fn process(data: Vec<i32>) -> i32 {
+    data.iter().map(|x| square(x)).sum()
+}
+
+fn square(x: &i32) -> i32 {
+    x * x
+}
+```
+
+**Steps:**
+1. Extract square() function
+2. Run tests
+3. Commit
+4. Replace loop with iterator
+5. Run tests
+6. Commit
+
+### Rename Variable/Function
+
+**When:** Name is unclear or misleading
+
+```rust
+// Before
+fn calc(d: Vec<i32>) -> f64 {
+    let s: i32 = d.iter().sum();
+    s as f64 / d.len() as f64
+}
+
+// After - Step by step
+// Step 1: Rename function
+fn calculate_average(d: Vec<i32>) -> f64 { ... }  // Test, commit
+
+// Step 2: Rename parameter
+fn calculate_average(data: Vec<i32>) -> f64 { ... }  // Test, commit
+
+// Step 3: Rename variable
+fn calculate_average(data: Vec<i32>) -> f64 {
+    let sum: i32 = data.iter().sum();  // Test, commit
+    sum as f64 / data.len() as f64
+}
+```
+
+### Extract Class/Struct
+
+**When:** Class has multiple responsibilities
+
+```rust
+// Before: God object
+struct UserService {
+    db: Database,
+    email_validator: Regex,
+    name_validator: Regex,
+}
+
+// After: Single responsibility
+struct UserService {
+    db: Database,
+    validator: UserValidator,  // EXTRACTED
+}
+
+struct UserValidator {
+    email_pattern: Regex,
+    name_pattern: Regex,
+}
+```
+
+**Steps:**
+1. Create empty UserValidator struct
+2. Test, commit
+3. Move email_validator field
+4. Test, commit
+5. Move name_validator field
+6. Test, commit
+7. Update UserService to use UserValidator
+8. Test, commit
+
+### Inline Unnecessary Abstraction
+
+**When:** Abstraction adds no value
+
+```rust
+// Before: Pointless wrapper
+fn get_user_email(user: &User) -> &str {
+    &user.email
+}
+
+fn process() {
+    let email = get_user_email(&user);  // Just use user.email!
+}
+
+// After: Inline
+fn process() {
+    let email = &user.email;
+}
+```
+
+**Steps:**
+1. Replace one call site with direct access
+2. Test, commit
+3. Replace next call site
+4. Test, commit
+5. Remove wrapper function
+6. Test, commit
+