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**Table of Contents**

- [Pack System: FMEA Analysis and User Workflows](#pack-system-fmea-analysis-and-user-workflows)
  - [Overview](#overview)
  - [User Workflow Categories](#user-workflow-categories)
  - [FMEA Table](#fmea-table)
    - [1. Discovery Workflows](#1-discovery-workflows)
    - [2. Installation Workflows](#2-installation-workflows)
    - [3. Generation Workflows](#3-generation-workflows)
    - [4. Composition Workflows](#4-composition-workflows)
    - [5. Validation Workflows](#5-validation-workflows)
    - [6. Publishing Workflows](#6-publishing-workflows)
  - [Risk Priority Numbers (RPN)](#risk-priority-numbers-rpn)
    - [Critical Risks (RPN > 100)](#critical-risks-rpn--100)
  - [User Journey Maps](#user-journey-maps)
    - [Happy Path: First-Time User Generates Project](#happy-path-first-time-user-generates-project)
    - [Power User: Compose Multi-Pack Project](#power-user-compose-multi-pack-project)
    - [Pack Author: Publish Custom Pack](#pack-author-publish-custom-pack)
  - [Mitigation Strategies](#mitigation-strategies)
    - [High-Priority Mitigations (P0)](#high-priority-mitigations-p0)
    - [Medium-Priority Mitigations (P1)](#medium-priority-mitigations-p1)
    - [Low-Priority Mitigations (P2)](#low-priority-mitigations-p2)
  - [Success Metrics](#success-metrics)
  - [Conclusion](#conclusion)

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# Pack System: FMEA Analysis and User Workflows

## Overview

This document provides a Failure Mode and Effects Analysis (FMEA) for the packs system, focusing on user-facing workflows and potential failure modes.

---

## User Workflow Categories

1. **Discovery Workflows**: Finding and exploring packs
2. **Installation Workflows**: Installing and managing packs
3. **Generation Workflows**: Creating projects from packs
4. **Composition Workflows**: Multi-pack project generation
5. **Validation Workflows**: Ensuring pack quality
6. **Publishing Workflows**: Sharing packs with community

---

## FMEA Table

### 1. Discovery Workflows

| Workflow | User Task | Potential Failure Mode | Effect | Severity | Likelihood | Detection | Mitigation | RPN |
|----------|-----------|----------------------|--------|----------|------------|-----------|------------|-----|
| **Search Packs** | User searches for "microservice rust" | No results found | User cannot find relevant packs | Medium | Low | High | Improve search indexing, suggest alternatives | 30 |
| | | Search returns irrelevant results | User wastes time | Low | Medium | High | Implement relevance scoring, user ratings | 20 |
| | | Search times out | User frustrated, retries | Medium | Low | High | Add search caching, optimize queries | 25 |
| **List Packs** | User lists all available packs | Registry unavailable | User cannot see any packs | High | Low | High | Fallback to local cache, offline mode | 40 |
| | | Large result set overwhelms user | User cannot find what they need | Low | High | Medium | Implement pagination, filters | 40 |
| **Show Pack Details** | User views pack details | Pack manifest corrupted | User sees incomplete information | Medium | Low | High | Validate manifests on install, checksums | 30 |
| | | Missing documentation | User doesn't understand pack | Medium | Medium | Low | Enforce documentation in validation | 60 |
| | | Outdated metadata | User confused about features | Low | Medium | Low | Auto-update metadata on publish | 40 |

---

### 2. Installation Workflows

| Workflow | User Task | Potential Failure Mode | Effect | Severity | Likelihood | Detection | Mitigation | RPN |
|----------|-----------|----------------------|--------|----------|------------|-----------|------------|-----|
| **Install Pack** | User installs startup-pack | Network failure during download | Installation fails mid-process | High | Medium | High | Implement resume/retry, local mirrors | 60 |
| | | Dependency conflict | Pack cannot be installed | High | Medium | Medium | Pre-install validation, dependency resolution | 80 |
| | | Insufficient disk space | Installation fails | High | Low | High | Check space before install, clear cache | 35 |
| | | Version not found | User gets wrong version | High | Low | High | Validate version exists before install | 35 |
| **Uninstall Pack** | User uninstalls pack | Pack still in use by other packs | Breaks dependent packs | High | Medium | Low | Warn about dependents, offer cascade uninstall | 90 |
| | | Files locked by system | Uninstall incomplete | Medium | Low | High | Retry with elevated permissions | 30 |
| **Update Pack** | User updates to latest version | Breaking changes in new version | User's project breaks | Critical | Medium | Low | Changelog warnings, version pinning | 120 |
| | | Update corrupts installation | Pack unusable | High | Low | High | Backup before update, rollback support | 40 |

---

### 3. Generation Workflows

| Workflow | User Task | Potential Failure Mode | Effect | Severity | Likelihood | Detection | Mitigation | RPN |
|----------|-----------|----------------------|--------|----------|------------|-----------|------------|-----|
| **Generate Project** | User generates from startup-pack | Missing required variables | Generation fails immediately | High | High | High | Interactive prompts, clear error messages | 60 |
| | | Template rendering error | Partial project generated | High | Medium | High | Atomic generation, rollback on failure | 60 |
| | | Output directory exists | Overwrites user files | Critical | Medium | Medium | Confirm overwrite, backup option | 120 |
| | | SPARQL query fails | Missing generated files | Medium | Low | High | Make queries optional, fallback values | 30 |
| | | Hook execution fails | Project in inconsistent state | High | Medium | Medium | Continue on hook failure, log errors | 80 |
| **Dry Run** | User previews generation | Dry run doesn't match actual | User surprised by actual generation | High | Low | Low | Ensure dry run uses same code path | 60 |
| | | Dry run too slow | User gives up | Low | Low | High | Optimize plan calculation | 10 |
| **Interactive Generation** | User prompted for variables | Too many prompts | User overwhelmed | Medium | High | Low | Group related variables, smart defaults | 80 |
| | | Invalid input accepted | Generation fails later | High | Medium | Medium | Validate input immediately | 80 |
| **Regenerate** | User regenerates parts of project | Overwrites manual changes | User loses work | Critical | High | Low | Detect manual changes, selective merge | 140 |
| | | Wrong files regenerated | Breaks working project | High | Medium | Low | Clear documentation of what's regenerated | 90 |

---

### 4. Composition Workflows

| Workflow | User Task | Potential Failure Mode | Effect | Severity | Likelihood | Detection | Mitigation | RPN |
|----------|-----------|----------------------|--------|----------|------------|-----------|------------|-----|
| **Compose Multiple Packs** | User composes 3 packs | File conflicts not detected | Files silently overwritten | Critical | High | Low | Pre-composition conflict analysis | 140 |
| | | Dependency conflicts | Composition fails | High | High | Medium | Smart dependency resolution | 90 |
| | | Incompatible packs | Generated project doesn't work | Critical | Medium | Low | Compatibility checking, warnings | 120 |
| | | Wrong execution order | Dependencies missing at generation time | High | Medium | Medium | Topological sort of templates | 80 |
| **Conflict Resolution** | User resolves file conflicts | Wrong conflict resolution chosen | Files incorrectly merged | High | High | Low | Preview merge results, undo option | 110 |
| | | Interactive prompts timeout | Default resolution applied | Medium | Low | High | Reasonable timeout, persist choices | 30 |
| **Load Composition File** | User loads composition.yaml | Malformed YAML | Load fails with cryptic error | Medium | Medium | High | Validate YAML, helpful error messages | 40 |
| | | Referenced packs not installed | Composition incomplete | High | Medium | High | Auto-install missing packs, clear error | 60 |

---

### 5. Validation Workflows

| Workflow | User Task | Potential Failure Mode | Effect | Severity | Likelihood | Detection | Mitigation | RPN |
|----------|-----------|----------------------|--------|----------|------------|-----------|------------|-----|
| **Validate Pack** | User validates custom pack | False positives | User wastes time fixing non-issues | Low | Medium | Low | Tune validation rules, user feedback | 40 |
| | | False negatives | Invalid pack passes validation | High | Low | Low | Comprehensive test suite | 60 |
| | | Validation too slow | User skips validation | Medium | Medium | High | Optimize validators, parallel checks | 40 |
| **Check Compatibility** | User checks pack compatibility | Incompatibility not detected | User generates broken project | Critical | Medium | Low | Comprehensive compatibility tests | 120 |
| | | Compatible packs marked incompatible | User doesn't use valid combination | Medium | Low | Medium | Review compatibility rules | 30 |
| **Lint Pack** | User lints pack | Too many warnings | User ignores all warnings | Low | High | Low | Categorize warnings, suppress non-critical | 50 |
| | | Auto-fix breaks pack | Pack unusable after lint --fix | High | Low | High | Test auto-fixes, backup before fix | 35 |
| **Score Pack** | User checks pack maturity | Score doesn't reflect quality | User trusts low-quality pack | High | Medium | Low | Review scoring algorithm, user ratings | 90 |
| | | Scoring biased towards certain patterns | Good packs score low | Medium | Medium | Medium | Diversify scoring criteria | 60 |

---

### 6. Publishing Workflows

| Workflow | User Task | Potential Failure Mode | Effect | Severity | Likelihood | Detection | Mitigation | RPN |
|----------|-----------|----------------------|--------|----------|------------|-----------|------------|-----|
| **Publish Pack** | User publishes custom pack | Invalid pack published | Other users cannot use pack | High | Low | High | Pre-publish validation, automated tests | 35 |
| | | Authentication fails | User frustrated, doesn't publish | Low | Low | High | Clear auth instructions, token refresh | 10 |
| | | Version collision | Publish rejected | Medium | Medium | High | Check version uniqueness before publish | 40 |
| | | Missing license | Legal issues | High | Medium | High | Require license in manifest | 60 |
| **Create Pack** | User creates new pack with wizard | Wizard doesn't cover use case | User creates invalid pack | High | Medium | Low | Flexible wizard, expert mode | 90 |
| | | Too many wizard steps | User gives up | Low | Medium | High | Skip optional steps, save progress | 30 |
| **Update Published Pack** | User publishes new version | Breaking changes not documented | Users upgrade and projects break | Critical | High | Low | Enforce changelog, breaking change warnings | 140 |
| | | Old version removed | Users cannot pin versions | High | Low | High | Keep all versions, deprecation policy | 35 |

---

## Risk Priority Numbers (RPN)

RPN = Severity × Likelihood × Detection (inverted)

**Risk Levels:**
- **Critical** (RPN > 100): Immediate attention required
- **High** (RPN 60-100): Priority fixes
- **Medium** (RPN 30-60): Address in next iteration
- **Low** (RPN < 30): Monitor

### Critical Risks (RPN > 100)

| Risk | RPN | Mitigation Priority |
|------|-----|-------------------|
| Breaking changes in pack updates | 120 | **P0** - Implement changelog enforcement, semantic versioning |
| Output directory overwrite without warning | 120 | **P0** - Add confirmation prompts, backup option |
| File conflicts not detected in composition | 140 | **P0** - Pre-composition conflict analysis |
| Regenerate overwrites manual changes | 140 | **P0** - Detect changes, selective merge |
| Breaking changes not documented | 140 | **P0** - Enforce changelog, semantic versioning |
| Incompatible packs not detected | 120 | **P0** - Comprehensive compatibility checking |
| Incompatibility not detected in validation | 120 | **P1** - Expand compatibility test suite |

---

## User Journey Maps

### Happy Path: First-Time User Generates Project

1. **Discover** → User searches for "startup microservice"
   - **Success**: Finds startup-pack with 4.8/5 rating
   - **Failure Mode**: No results (RPN: 30)

2. **Explore** → User views pack details
   - **Success**: Sees templates, variables, examples
   - **Failure Mode**: Missing documentation (RPN: 60)

3. **Install** → User runs `ggen pack install startup-pack`
   - **Success**: Pack installed in 2 seconds
   - **Failure Mode**: Network failure (RPN: 60)

4. **Generate** → User runs `ggen pack generate startup-pack --output my-app`
   - **Success**: Project generated in 8 seconds
   - **Failure Mode**: Missing variables (RPN: 60)

5. **Verify** → User explores generated project
   - **Success**: All files present, builds successfully
   - **Failure Mode**: Template rendering error (RPN: 60)

6. **Use** → User develops on generated project
   - **Success**: Productive development
   - **Failure Mode**: Generated code doesn't work (RPN: 100)

---

### Power User: Compose Multi-Pack Project

1. **Plan** → User creates composition.yaml
   - **Success**: Valid composition with 3 packs
   - **Failure Mode**: Malformed YAML (RPN: 40)

2. **Validate** → User runs `ggen pack plan --composition-file composition.yaml`
   - **Success**: No conflicts, clear execution plan
   - **Failure Mode**: Conflicts not detected (RPN: 140)

3. **Resolve** → User resolves conflicts interactively
   - **Success**: Smart merge, no data loss
   - **Failure Mode**: Wrong conflict resolution (RPN: 110)

4. **Compose** → User runs `ggen pack compose --composition-file composition.yaml`
   - **Success**: All packs merged successfully
   - **Failure Mode**: Dependency conflicts (RPN: 90)

5. **Test** → User tests generated project
   - **Success**: All integrations work
   - **Failure Mode**: Incompatible packs (RPN: 120)

---

### Pack Author: Publish Custom Pack

1. **Create** → Author runs `ggen pack create --name my-pack`
   - **Success**: Pack structure created
   - **Failure Mode**: Wizard doesn't cover use case (RPN: 90)

2. **Develop** → Author adds templates and configuration
   - **Success**: Pack manifest complete
   - **Failure Mode**: Invalid configuration (RPN: 60)

3. **Validate** → Author runs `ggen pack validate .`
   - **Success**: Pack scores 85/100
   - **Failure Mode**: False positives (RPN: 40)

4. **Test** → Author generates test project
   - **Success**: Generation works as expected
   - **Failure Mode**: Edge cases not tested (RPN: 80)

5. **Publish** → Author runs `ggen pack publish .`
   - **Success**: Pack published to registry
   - **Failure Mode**: Missing license (RPN: 60)

6. **Maintain** → Author publishes updates
   - **Success**: Users upgrade smoothly
   - **Failure Mode**: Breaking changes not documented (RPN: 140)

---

## Mitigation Strategies

### High-Priority Mitigations (P0)

1. **Pre-Generation Conflict Analysis**
   - Scan for file conflicts before generation
   - Show conflict resolution options
   - Preview merge results

2. **Selective Regeneration with Change Detection**
   - Git diff to detect manual changes
   - Prompt user to review changes
   - Three-way merge for modified files

3. **Changelog Enforcement**
   - Require CHANGELOG.md for version updates
   - Parse changelog for breaking changes
   - Warn users before upgrading

4. **Overwrite Protection**
   - Always check if output directory exists
   - Confirm overwrite with clear warnings
   - Offer backup before overwrite

5. **Comprehensive Compatibility Testing**
   - Test all common pack combinations
   - Automated compatibility matrix
   - User-reported incompatibilities

### Medium-Priority Mitigations (P1)

6. **Smart Dependency Resolution**
   - Automatic version conflict resolution
   - Suggest compatible versions
   - Visualize dependency tree

7. **Interactive Variable Collection**
   - Group related variables
   - Smart defaults from project context
   - Validate input immediately

8. **Validation Tuning**
   - Categorize warnings by severity
   - Allow suppression of specific warnings
   - Community feedback on rules

### Low-Priority Mitigations (P2)

9. **Search Relevance Improvements**
   - User ratings and downloads weighting
   - Synonym expansion
   - Typo tolerance

10. **Performance Optimizations**
    - Parallel template rendering
    - Incremental SPARQL queries
    - Smart caching strategies

---

## Success Metrics

| Metric | Target | Measurement |
|--------|--------|-------------|
| First-time generation success rate | > 90% | Telemetry |
| User-reported pack conflicts | < 5% | Issue tracker |
| Average time to first successful generation | < 5 minutes | User surveys |
| Pack validation accuracy | > 95% | False positive/negative rate |
| Breaking change detection rate | 100% | Automated tests |
| User satisfaction with conflict resolution | > 4.0/5 | Post-generation survey |

---

## Conclusion

The FMEA analysis identifies **7 critical risks** (RPN > 100) that require immediate attention:

1. Breaking changes in updates (RPN: 140)
2. Overwrites without warning (RPN: 120-140)
3. Conflict detection failures (RPN: 120-140)
4. Compatibility checking gaps (RPN: 120)

Addressing these P0 mitigations will provide a **robust, user-friendly packs system** that enables safe, predictable multi-pack project generation.
