Build Fix

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description: Automatically fix build errors systematically
allowed-tools: Bash(npm run build:*), Bash(yarn build:*), Bash(tsc:*), Bash(cargo build:*), Bash(go build:*), Bash(mvn compile:*), Read, Edit, Write
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# Build Fix Command

Automatically fix build errors systematically.

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## Usage

/build-fix

No arguments needed - analyzes current build errors and fixes them.

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## What This Command Does

1. **Runs Build**: Executes project build command
2. **Triages Errors**: Categorizes and prioritizes errors
3. **Fixes Iteratively**: Resolves errors one category at a time
4. **Verifies Fix**: Rebuilds after each fix to confirm resolution
5. **Reports Progress**: Shows errors fixed and remaining

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## How It Works

### Error Triage

**Priority 1 (Critical):**
- Syntax errors
- Missing imports
- Type errors in core files

**Priority 2 (High):**
- Type mismatches
- Unused variables/imports
- Interface violations

**Priority 3 (Medium):**
- Linting errors
- Deprecation warnings
- Style violations

**Priority 4 (Low):**
- Non-critical warnings
- Documentation issues

### Fix Strategy

1. **Group Similar Errors**: Fix all imports together, all type errors together, etc.
2. **Fix Root Causes First**: Resolve core issues before dependent errors
3. **Incremental Verification**: Rebuild after each batch to catch regressions
4. **Smart Fixes**: Apply pattern-based fixes across multiple files

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## Example Session

User: /build-fix

Build Error Resolver: Running build to identify errors...

=== Build Analysis === Found 47 errors across 12 files

Error Categories:

• Type errors: 23 (Priority 1)
• Missing imports: 15 (Priority 1)
• Unused variables: 7 (Priority 2)
• Linting issues: 2 (Priority 3)

Starting with Priority 1 errors...

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Round 1: Fixing Missing Imports

Files affected: 5 files

• UserService.ts: Missing import for 'User' type
• AuthController.ts: Missing import for 'validateEmail'
• PostService.ts: Missing import for 'Post' type
• ...

Applied fixes to 5 files.

Rebuilding... ✅ 15 errors resolved!

Remaining: 32 errors

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Round 2: Fixing Type Errors

Files affected: 8 files

• UserService.ts:42 - Property 'id' missing in type 'UserInput'
• PostController.ts:67 - Argument type mismatch
• ...

Analyzing type errors...

Issue 1: UserInput interface incomplete Fix: Added 'id' field to UserInput interface

Issue 2: Function signature mismatch Fix: Updated createPost call to match new signature

Applied fixes to 8 files.

Rebuilding... ✅ 20 errors resolved!

Remaining: 12 errors

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Round 3: Fixing Unused Variables

Files affected: 4 files

• UserService.ts:15 - Unused variable 'result'
• PostService.ts:23 - Unused import 'moment'
• ...

Applied fixes to 4 files.

Rebuilding... ✅ 7 errors resolved!

Remaining: 5 errors

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Round 4: Fixing Linting Issues

Files affected: 2 files

• Minor formatting issues
• Prefer const over let

Applied fixes to 2 files.

Rebuilding... ✅ 2 errors resolved!

Remaining: 3 errors

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Manual Intervention Needed

The following errors require human decision:

1. AuthController.ts:156 Error: Cannot determine which overload to use Context: Multiple JWT signing methods available Suggestion: Specify explicit types or use specific overload

2. UserService.ts:89 Error: Possible null reference Context: User lookup might return null Suggestion: Add null check or use optional chaining

3. database.ts:34 Error: Module not found '@supabase/supabase-js' Context: Missing dependency Suggestion: Run 'npm install @supabase/supabase-js'

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=== Summary === ✅ Fixed: 44 errors (94%) ⚠️ Manual: 3 errors (6%)

Next steps:

1. Review manual intervention items above
2. Install missing dependencies if needed
3. Add null checks where indicated
4. Rerun build to verify

Great progress! Most errors are resolved.

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## Command Behavior

**Delegates to**: `devops-specialist` agent

**Build Commands Detected**:
- `npm run build`
- `yarn build`
- `tsc`
- `cargo build`
- `go build`
- `mvn compile`

**Automatic Detection**: Finds build command from package.json or project structure

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## Error Categories

### Syntax Errors
- Missing brackets, semicolons
- Invalid syntax
- **Auto-fix**: Yes

### Type Errors
- Type mismatches
- Missing properties
- Interface violations
- **Auto-fix**: Yes (most cases)

### Import Errors
- Missing imports
- Incorrect import paths
- Circular dependencies
- **Auto-fix**: Yes (missing imports), No (circular deps)

### Linting Errors
- Style violations
- Unused code
- Complexity warnings
- **Auto-fix**: Yes

### Dependency Errors
- Missing packages
- Version conflicts
- **Auto-fix**: No (requires manual install)

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## Best Practices

### Do:
- ✅ Run on clean git state (easy to revert)
- ✅ Review fixes before committing
- ✅ Let it fix multiple files at once
- ✅ Re-run until all auto-fixable errors resolved
- ✅ Read manual intervention suggestions

### Don't:
- ❌ Run with uncommitted changes
- ❌ Skip manual review of fixes
- ❌ Ignore manual intervention items
- ❌ Fix errors manually while command runs
- ❌ Interrupt mid-fix

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## When to Use

- ✅ After major refactoring
- ✅ After dependency updates
- ✅ When build errors are overwhelming
- ✅ Before merging branches
- ✅ After code generation

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## Safety Features

**Incremental Fixes**: Fixes are applied gradually with verification

**Rollback Ready**: Works best on clean git state for easy revert

**Verification**: Rebuilds after each batch to catch regressions

**Manual Escalation**: Flags errors that need human decision

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## Related Commands

- `/checkpoint` - Run tests, build, and full verification
- `/refactor-clean` - Clean up after build fixes
- `/review` - Review all applied fixes

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## Tips

**Start Fresh**: Commit or stash changes before running

**Trust the Process**: Let it work through errors systematically

**Review Carefully**: Auto-fixes are usually correct but verify

**Handle Manual Items**