# Architecture Audit Report

**Branch**: refactor/bootstrap-extraction
**Base**: main
**Date**: 2025-12-15 21:53:00
**Commit**: 8c46ba4 refactor: extract handler setup from bootstrap into dedicated module

---

## Files Changed

| File | Status |
|------|--------|
| src/services/handler-setup.ts | NEW (242 lines) |
| src/bootstrap.ts | MODIFIED (-141 lines, +10 lines) |
| tests/unit/services/handler-setup.test.ts | NEW (218 lines) |

---

## Executive Summary

This PR extracts event handler setup logic from `bootstrap.ts` into a dedicated `handler-setup.ts` module. The refactoring is well-executed, follows existing architectural patterns, and improves maintainability. There are no blocking issues.

**Architecture Score**: 8/10

**Verdict**: APPROVED

---

## [RED CIRCLE] Issues in Your Changes (BLOCKING)

**None identified.**

The changes are functionally equivalent to the original code. The extraction maintains the same handler initialization order and error handling behavior.

---

## [YELLOW TRIANGLE] Issues in Code You Touched (Should Fix)

### 1. DependencyHandler Not Tracked in Registry (MEDIUM)

**Location**: `/workspace/delegate/src/services/handler-setup.ts:217-234`

**Issue**: The `DependencyHandler` is created via factory pattern but is NOT added to the registry. This means:
- `registry.shutdown()` will not call teardown on `DependencyHandler`
- The handler count in logs (line 238) shows `totalHandlers: standardHandlers.length + 1` but registry only contains 6 handlers
- Lifecycle management is inconsistent between standard handlers and DependencyHandler

**Code**:
```typescript
// Line 219 comment: "Cannot use registry because create() does its own event subscription"
const dependencyHandlerResult = await DependencyHandler.create(
  deps.dependencyRepository,
  deps.taskRepository,
  logger,
  eventBus
);
```

**Impact**: If shutdown is called on the registry, DependencyHandler event subscriptions will not be cleaned up, potentially causing memory leaks or orphaned handlers.

**Recommendation**: Either:
1. Modify DependencyHandler to conform to the standard handler pattern (setup method instead of create factory)
2. Add DependencyHandler to a separate tracking mechanism and expose a unified shutdown
3. Document this as an intentional architectural exception

---

### 2. Missing Logger Log Message Removal (LOW)

**Location**: `/workspace/delegate/src/bootstrap.ts:310` (removed)

**Issue**: The original bootstrap had `logger.info('Event-driven architecture initialized successfully')` after all handlers were set up. This log message is now gone - the new handler-setup.ts logs at a different level/module context.

**Old code** (removed):
```typescript
logger.info('Event-driven architecture initialized successfully');
```

**New code** (different context):
```typescript
setupLogger.info('Event handlers initialized successfully', {
  standardHandlers: standardHandlers.length,
  totalHandlers: standardHandlers.length + 1
});
```

**Impact**: Minor observability change - log message now appears under 'HandlerSetup' module context rather than TaskManager registration context.

**Recommendation**: This is acceptable; the new log message is actually more informative with handler counts.

---

### 3. Test Uses Implementation Details for Assertion (LOW)

**Location**: `/workspace/delegate/tests/unit/services/handler-setup.test.ts:189`

**Issue**: The test accesses private implementation details to verify handler setup:
```typescript
const subscriptionCount = (eventBus as any).handlers?.size ?? 0;
```

**Impact**: This assertion is brittle - if InMemoryEventBus changes its internal structure, the test breaks even if functionality is correct.

**Recommendation**: Either:
1. Add a public method to EventBus like `getSubscriptionCount()` for testing
2. Test observable behavior instead (emit events and verify handlers respond)
3. Accept this as a pragmatic compromise and document it

---

## [INFO CIRCLE] Pre-existing Issues (Not Blocking)

### 1. Container Type Safety (PRE-EXISTING)

**Location**: `/workspace/delegate/src/services/handler-setup.ts:72`

**Issue**: The `getDependency` function uses `as T` cast which loses type safety:
```typescript
return ok(result.value as T);
```

This is consistent with the existing pattern in `bootstrap.ts` (`getFromContainer`, `getFromContainerSafe`), so it is not introduced by this PR.

---

### 2. Repetitive Error Handling Pattern (PRE-EXISTING)

**Location**: `/workspace/delegate/src/services/handler-setup.ts:85-127`

**Issue**: The dependency extraction follows a repetitive pattern that could be simplified with a utility function:
```typescript
const configResult = getDependency<Configuration>(container, 'config');
if (!configResult.ok) return configResult;

const loggerResult = getDependency<Logger>(container, 'logger');
if (!loggerResult.ok) return loggerResult;
// ... 8 more times
```

This is not a problem introduced by this PR - it mirrors the original bootstrap.ts pattern. A potential improvement would be a `collectDependencies` helper that gathers all in one pass and reports which are missing.

---

### 3. Dead Code: getConfig Function (PRE-EXISTING)

**Location**: `/workspace/delegate/src/bootstrap.ts:52-63`

**Issue**: The `getConfig()` function is defined but never used. It existed before this PR.

---

## Positive Observations

### 1. Clean Separation of Concerns
The extraction creates a clear boundary: bootstrap.ts handles DI container setup, handler-setup.ts handles event handler wiring. This follows the Single Responsibility Principle.

### 2. Explicit Dependencies Interface
```typescript
export interface HandlerDependencies {
  readonly config: Configuration;
  readonly logger: Logger;
  // ... 8 more
}
```
This makes the handler setup's requirements explicit and testable. Much better than having handlers reach into the container themselves.

### 3. Proper Error Cleanup
```typescript
if (!initResult.ok) {
  // Cleanup any handlers that were already initialized
  await registry.shutdown();
  return err(new DelegateError(...));
}
```
The new code properly cleans up on failure, which the original bootstrap.ts did not do consistently.

### 4. Comprehensive Tests
The test file covers:
- Happy path (all dependencies present)
- Missing dependency errors (config, logger, eventBus, taskRepository)
- Registry lifecycle management
- Handler initialization

### 5. Documentation
Architecture comments explain the design decisions:
```typescript
// ARCHITECTURE: 6 standard handlers use setup(eventBus) pattern via registry
// DependencyHandler uses factory pattern (create()) for async graph initialization
```

---

## Summary

**Your Changes:**
- [RED CIRCLE] CRITICAL: 0
- [RED CIRCLE] HIGH: 0
- [YELLOW TRIANGLE] MEDIUM: 1 (DependencyHandler not in registry)

**Code You Touched:**
- [YELLOW TRIANGLE] LOW: 2 (log message change, test implementation detail access)

**Pre-existing:**
- [INFO CIRCLE] LOW: 3 (type safety, repetitive pattern, dead code)

---

## Merge Recommendation

**[GREEN CHECK] APPROVED**

The refactoring is sound and improves code maintainability. The DependencyHandler lifecycle management issue (MEDIUM) should be tracked but is not a regression - the same behavior existed before; the new code just makes it more visible.

**Before merge, consider:**
1. Adding a TODO comment about DependencyHandler lifecycle management for v0.4.0
2. Deciding whether the HandlerSetupResult should include the DependencyHandler instance for unified shutdown

**No blocking issues. PR is ready for merge.**
