Tech Stack Evaluation — Metrics, Workflows, and Examples
| Field | Value |
|---|---|
| Type | Skill Resource |
| Source | ~/.copilot/skills/architecture/references/tech-stack-evaluation.md |
| Description | Not specified |
Source Content
Tech Stack Evaluation — Metrics, Workflows, and Examples
Reference material for comparing frameworks, databases, clouds, and vendors: the scoring and financial formulas, the step-by-step evaluation workflows, and worked input/output examples. Validate a comparison report with scripts/lint_comparison.sh.
The sample fixtures in assets/ (sample_input_tco.json, sample_input_structured.json, sample_input_text.json, expected_output_comparison.json) are illustrative inputs for the scripts below — pass them explicitly via CLI flags (for example --input assets/sample_input_tco.json); no script auto-loads them by relative path.
Part 1 — Metrics and Calculations
Detailed metrics and calculations used in technology stack evaluation.
Table of Contents
- Scoring and Comparison
- Financial Calculations
- Ecosystem Health Metrics
- Security Metrics
- Migration Metrics
- Performance Benchmarks
Scoring and Comparison
Technology Comparison Matrix
| Metric | Scale | Description |
|---|---|---|
| Feature Completeness | 0-100 | Coverage of required features |
| Learning Curve | Easy/Medium/Hard | Time to developer proficiency |
| Developer Experience | 0-100 | Tooling, debugging, workflow quality |
| Documentation Quality | 0-10 | Completeness, clarity, examples |
Weighted Scoring Algorithm
The comparator uses normalized weighted scoring:
# Default category weights (sum to 100%)weights = { "performance": 15, "scalability": 15, "developer_experience": 20, "ecosystem": 15, "learning_curve": 10, "documentation": 10, "community_support": 10, "enterprise_readiness": 5}
# Final score calculationweighted_score = sum(category_score * weight / 100 for each category)Confidence Scoring
Confidence is calculated based on score gap between top options:
| Score Gap | Confidence Level |
|---|---|
| < 5 points | Low (40-50%) |
| 5-15 points | Medium (50-70%) |
| > 15 points | High (70-100%) |
Financial Calculations
TCO Components
Initial Costs (One-Time)
- Licensing fees
- Training:
team_size * hours_per_dev * hourly_rate + materials - Migration costs
- Setup and tooling
Operational Costs (Annual)
- Licensing renewals
- Hosting:
base_cost * (1 + growth_rate)^(year - 1) - Support contracts
- Maintenance:
team_size * hours_per_dev_monthly * hourly_rate * 12
Scaling Costs
- Infrastructure:
servers * cost_per_server * 12 - Cost per user:
total_yearly_cost / user_count
ROI Calculations
productivity_value = additional_features_per_year * avg_feature_valuenet_tco = total_cost - (productivity_value * years)roi_percentage = (benefits - costs) / costs * 100Cost Per Metric Reference
| Metric | Description |
|---|---|
| Cost per user | Monthly or yearly per active user |
| Cost per API request | Average cost per 1000 requests |
| Cost per GB | Storage and transfer costs |
| Cost per compute hour | Processing time costs |
Ecosystem Health Metrics
GitHub Health Score (0-100)
| Metric | Max Points | Thresholds |
|---|---|---|
| Stars | 30 | 50K+: 30, 20K+: 25, 10K+: 20, 5K+: 15, 1K+: 10 |
| Forks | 20 | 10K+: 20, 5K+: 15, 2K+: 12, 1K+: 10 |
| Contributors | 20 | 500+: 20, 200+: 15, 100+: 12, 50+: 10 |
| Commits/month | 30 | 100+: 30, 50+: 25, 25+: 20, 10+: 15 |
npm Health Score (0-100)
| Metric | Max Points | Thresholds |
|---|---|---|
| Weekly downloads | 40 | 1M+: 40, 500K+: 35, 100K+: 30, 50K+: 25, 10K+: 20 |
| Major version | 20 | v5+: 20, v3+: 15, v1+: 10 |
| Dependencies | 20 | ≤10: 20, ≤25: 15, ≤50: 10 (fewer is better) |
| Days since publish | 20 | ≤30: 20, ≤90: 15, ≤180: 10, ≤365: 5 |
Community Health Score (0-100)
| Metric | Max Points | Thresholds |
|---|---|---|
| Stack Overflow questions | 25 | 50K+: 25, 20K+: 20, 10K+: 15, 5K+: 10 |
| Job postings | 25 | 5K+: 25, 2K+: 20, 1K+: 15, 500+: 10 |
| Tutorials | 25 | 1K+: 25, 500+: 20, 200+: 15, 100+: 10 |
| Forum/Discord members | 25 | 50K+: 25, 20K+: 20, 10K+: 15, 5K+: 10 |
Corporate Backing Score
| Backing Type | Score |
|---|---|
| Major tech company (Google, Microsoft, Meta) | 100 |
| Established company (Vercel, HashiCorp) | 80 |
| Funded startup | 60 |
| Community-led (strong community) | 40 |
| Individual maintainers | 20 |
Security Metrics
Security Scoring Components
| Metric | Description |
|---|---|
| CVE Count (12 months) | Known vulnerabilities in last year |
| CVE Count (3 years) | Longer-term vulnerability history |
| Severity Distribution | Critical/High/Medium/Low counts |
| Patch Frequency | Average days to patch vulnerabilities |
Compliance Readiness Levels
| Level | Score Range | Description |
|---|---|---|
| Ready | 90-100% | Meets compliance requirements |
| Mostly Ready | 70-89% | Minor gaps to address |
| Partial | 50-69% | Significant work needed |
| Not Ready | < 50% | Major gaps exist |
Compliance Framework Coverage
GDPR
- Data privacy features
- Consent management
- Data portability
- Right to deletion
SOC2
- Access controls
- Encryption at rest/transit
- Audit logging
- Change management
HIPAA
- PHI handling
- Encryption standards
- Access controls
- Audit trails
Migration Metrics
Complexity Scoring (1-10 Scale)
| Factor | Weight | Description |
|---|---|---|
| Code Changes | 30% | Lines of code affected |
| Architecture Impact | 25% | Breaking changes, API compatibility |
| Data Migration | 25% | Schema changes, data transformation |
| Downtime Requirements | 20% | Zero-downtime possible vs planned outage |
Effort Estimation
| Phase | Components |
|---|---|
| Development | Hours per component * complexity factor |
| Testing | Unit + integration + E2E hours |
| Training | Team size * learning curve hours |
| Buffer | 20-30% for unknowns |
Risk Assessment Matrix
| Risk Category | Factors Evaluated |
|---|---|
| Technical | API incompatibilities, performance regressions |
| Business | Downtime impact, feature parity gaps |
| Team | Learning curve, skill gaps |
Performance Benchmarks
Throughput/Latency Metrics
| Metric | Description |
|---|---|
| RPS | Requests per second |
| Avg Response Time | Mean response latency (ms) |
| P95 Latency | 95th percentile response time |
| P99 Latency | 99th percentile response time |
| Concurrent Users | Maximum simultaneous connections |
Resource Usage Metrics
| Metric | Unit |
|---|---|
| Memory | MB/GB per instance |
| CPU | Utilization percentage |
| Storage | GB required |
| Network | Bandwidth MB/s |
Scalability Characteristics
| Type | Description |
|---|---|
| Horizontal | Add more instances, efficiency factor |
| Vertical | CPU/memory limits per instance |
| Cost per Performance | Dollar per 1000 RPS |
| Scaling Inflection | Point where cost efficiency changes |
Part 2 — Evaluation Workflows
Step-by-step workflows for common evaluation scenarios.
Table of Contents
- Framework Comparison Workflow
- TCO Analysis Workflow
- Migration Assessment Workflow
- Security Evaluation Workflow
- Cloud Provider Selection Workflow
Framework Comparison Workflow
Use this workflow when comparing frontend/backend frameworks or libraries.
Step 1: Define Requirements
-
Identify the use case:
- What type of application? (SaaS, e-commerce, real-time, etc.)
- What scale? (users, requests, data volume)
- What team size and skill level?
-
Set priorities (weights must sum to 100%):
- Performance: ____%
- Scalability: ____%
- Developer Experience: ____%
- Ecosystem: ____%
- Learning Curve: ____%
- Other: ____%
-
List constraints:
- Budget limitations
- Timeline requirements
- Compliance needs
- Existing infrastructure
Step 2: Run Comparison
python scripts/stack_comparator.py \ --technologies "React,Vue,Angular" \ --use-case "enterprise-saas" \ --weights "performance:20,ecosystem:25,scalability:20,developer_experience:35"Step 3: Analyze Results
- Review weighted total scores
- Check confidence level (High/Medium/Low)
- Examine strengths and weaknesses for each option
- Review decision factors
Step 4: Validate Recommendation
- Match recommendation to your constraints
- Consider team skills and hiring market
- Evaluate ecosystem for your specific needs
- Check corporate backing and long-term viability
Step 5: Document Decision
Record:
- Final selection with rationale
- Trade-offs accepted
- Risks identified
- Mitigation strategies
TCO Analysis Workflow
Use this workflow for comprehensive cost analysis over multiple years.
Step 1: Gather Cost Data
Initial Costs:
- Licensing fees (if any)
- Training hours per developer
- Developer hourly rate
- Migration costs
- Setup and tooling costs
Operational Costs:
- Monthly hosting costs
- Annual support contracts
- Maintenance hours per developer per month
Scaling Parameters:
- Initial user count
- Expected annual growth rate
- Infrastructure scaling approach
Step 2: Run TCO Calculator
python scripts/tco_calculator.py \ --input assets/sample_input_tco.json \ --years 5 \ --output tco_report.jsonStep 3: Analyze Cost Breakdown
- Review initial vs. operational costs ratio
- Examine year-over-year cost growth
- Check cost per user trends
- Identify scaling efficiency
Step 4: Identify Optimization Opportunities
Review:
- Can hosting costs be reduced with reserved pricing?
- Can automation reduce maintenance hours?
- Are there cheaper alternatives for specific components?
Step 5: Compare Multiple Options
Run TCO analysis for each technology option:
- Current state (baseline)
- Option A
- Option B
Compare:
- 5-year total cost
- Break-even point
- Risk-adjusted costs
Migration Assessment Workflow
Use this workflow when planning technology migrations.
Step 1: Document Current State
- Count lines of code
- List all components/modules
- Identify dependencies
- Document current architecture
- Note existing pain points
Step 2: Define Target State
- Target technology/framework
- Target architecture
- Expected benefits
- Success criteria
Step 3: Assess Team Readiness
- How many developers have target technology experience?
- What training is needed?
- What is the team’s capacity during migration?
Step 4: Run Migration Analysis
python scripts/migration_analyzer.py \ --from "angular-1.x" \ --to "react" \ --codebase-size 50000 \ --components 200 \ --team-size 6Step 5: Review Risk Assessment
For each risk category:
- Identify specific risks
- Assess probability and impact
- Define mitigation strategies
- Assign risk owners
Step 6: Plan Migration Phases
-
Phase 1: Foundation
- Setup new infrastructure
- Create migration utilities
- Train team
-
Phase 2: Incremental Migration
- Migrate by feature area
- Maintain parallel systems
- Continuous testing
-
Phase 3: Completion
- Remove legacy code
- Optimize performance
- Complete documentation
-
Phase 4: Stabilization
- Monitor production
- Address issues
- Gather metrics
Step 7: Define Rollback Plan
Document:
- Trigger conditions for rollback
- Rollback procedure
- Data recovery steps
- Communication plan
Security Evaluation Workflow
Use this workflow for security and compliance assessment.
Step 1: Identify Requirements
-
List applicable compliance standards:
- GDPR
- SOC2
- HIPAA
- PCI-DSS
- Other: _____
-
Define security priorities:
- Data encryption requirements
- Access control needs
- Audit logging requirements
- Incident response expectations
Step 2: Gather Security Data
For each technology:
- CVE count (last 12 months)
- CVE count (last 3 years)
- Severity distribution
- Average patch time
- Security features list
Step 3: Run Security Assessment
python scripts/security_assessor.py \ --technology "express-js" \ --compliance "soc2,gdpr" \ --output security_report.jsonStep 4: Analyze Results
Review:
- Overall security score
- Vulnerability trends
- Patch responsiveness
- Compliance readiness per standard
Step 5: Identify Gaps
For each compliance standard:
- List missing requirements
- Estimate remediation effort
- Identify workarounds if available
- Calculate compliance cost
Step 6: Make Risk-Based Decision
Consider:
- Acceptable risk level
- Cost of remediation
- Alternative technologies
- Business impact of compliance gaps
Cloud Provider Selection Workflow
Use this workflow for AWS vs Azure vs GCP decisions.
Step 1: Define Workload Requirements
-
Workload type:
- Web application
- API services
- Data analytics
- Machine learning
- IoT
- Other: _____
-
Resource requirements:
- Compute: ____ instances, ____ cores, ____ GB RAM
- Storage: ____ TB, type (block/object/file)
- Database: ____ type, ____ size
- Network: ____ GB/month transfer
-
Special requirements:
- GPU/TPU for ML
- Edge computing
- Multi-region
- Specific compliance certifications
Step 2: Evaluate Feature Availability
For each provider, verify:
- Required services exist
- Service maturity level
- Regional availability
- SLA guarantees
Step 3: Run Cost Comparison
python scripts/tco_calculator.py \ --providers "aws,azure,gcp" \ --workload-config workload.json \ --years 3Step 4: Assess Ecosystem Fit
Consider:
- Team’s existing expertise
- Development tooling preferences
- CI/CD integration
- Monitoring and observability tools
Step 5: Evaluate Vendor Lock-in
For each provider:
- List proprietary services you’ll use
- Estimate migration cost if switching
- Identify portable alternatives
- Calculate lock-in risk score
Step 6: Make Final Selection
Weight factors:
- Cost: ____%
- Features: ____%
- Team expertise: ____%
- Lock-in risk: ____%
- Support quality: ____%
Select provider with highest weighted score.
Best Practices
For All Evaluations
- Document assumptions - Make all assumptions explicit
- Validate data - Verify metrics from multiple sources
- Consider context - Generic scores may not apply to your situation
- Include stakeholders - Get input from team members who will use the technology
- Plan for change - Technology landscapes evolve; plan for flexibility
Common Pitfalls to Avoid
- Over-weighting recent popularity vs. long-term stability
- Ignoring team learning curve in timeline estimates
- Underestimating migration complexity
- Assuming vendor claims are accurate
- Not accounting for hidden costs (training, hiring, technical debt)
Part 3 — Worked Examples
Concrete examples showing input formats and expected outputs.
Table of Contents
- Quick Comparison Example
- TCO Analysis Example
- Ecosystem Analysis Example
- Migration Assessment Example
- Multi-Technology Comparison
Quick Comparison Example
Input (Text Format)
Compare React vs Vue for building a SaaS dashboard.Focus on: developer productivity, ecosystem maturity, performance.Output
TECHNOLOGY COMPARISON: React vs Vue for SaaS Dashboard=======================================================
RECOMMENDATION: ReactConfidence: 78% (Medium-High)
COMPARISON MATRIX-----------------| Category | Weight | React | Vue ||----------------------|--------|-------|------|| Performance | 15% | 82.0 | 85.0 || Scalability | 15% | 88.0 | 80.0 || Developer Experience | 20% | 85.0 | 90.0 || Ecosystem | 15% | 92.0 | 78.0 || Learning Curve | 10% | 70.0 | 85.0 || Documentation | 10% | 88.0 | 82.0 || Community Support | 10% | 90.0 | 75.0 || Enterprise Readiness | 5% | 85.0 | 72.0 ||----------------------|--------|-------|------|| WEIGHTED TOTAL | 100% | 85.2 | 81.1 |
KEY DECISION FACTORS--------------------1. Ecosystem (15%): React leads with 92.0 - larger npm ecosystem2. Developer Experience (20%): Vue leads with 90.0 - gentler learning curve3. Community Support (10%): React leads with 90.0 - more Stack Overflow resources
PROS/CONS SUMMARY-----------------React: ✓ Excellent ecosystem (92.0/100) ✓ Strong community support (90.0/100) ✓ Excellent scalability (88.0/100) ✗ Steeper learning curve (70.0/100)
Vue: ✓ Excellent developer experience (90.0/100) ✓ Good performance (85.0/100) ✓ Easier learning curve (85.0/100) ✗ Smaller enterprise presence (72.0/100)TCO Analysis Example
Input (JSON Format)
{ "technology": "Next.js on Vercel", "team_size": 8, "timeline_years": 5, "initial_costs": { "licensing": 0, "training_hours_per_dev": 24, "developer_hourly_rate": 85, "migration": 15000, "setup": 5000 }, "operational_costs": { "monthly_hosting": 2500, "annual_support": 0, "maintenance_hours_per_dev_monthly": 16 }, "scaling_params": { "initial_users": 5000, "annual_growth_rate": 0.40, "initial_servers": 3, "cost_per_server_monthly": 150 }}Output
TCO ANALYSIS: Next.js on Vercel (5-Year Projection)====================================================
EXECUTIVE SUMMARY-----------------Total TCO: $1,247,320Net TCO (after productivity gains): $987,320Average Yearly Cost: $249,464
INITIAL COSTS (One-Time)------------------------| Component | Cost ||----------------|-----------|| Licensing | $0 || Training | $16,820 || Migration | $15,000 || Setup | $5,000 ||----------------|-----------|| TOTAL INITIAL | $36,820 |
OPERATIONAL COSTS (Per Year)----------------------------| Year | Hosting | Maintenance | Total ||------|----------|-------------|-----------|| 1 | $30,000 | $130,560 | $160,560 || 2 | $42,000 | $130,560 | $172,560 || 3 | $58,800 | $130,560 | $189,360 || 4 | $82,320 | $130,560 | $212,880 || 5 | $115,248 | $130,560 | $245,808 |
SCALING ANALYSIS----------------User Projections: 5,000 → 7,000 → 9,800 → 13,720 → 19,208Cost per User: $32.11 → $24.65 → $19.32 → $15.52 → $12.79Scaling Efficiency: Excellent - economies of scale achieved
KEY COST DRIVERS----------------1. Developer maintenance time ($652,800 over 5 years)2. Infrastructure/hosting ($328,368 over 5 years)
OPTIMIZATION OPPORTUNITIES--------------------------• Consider automation to reduce maintenance hours• Evaluate reserved capacity pricing for hostingEcosystem Analysis Example
Input
technology: "Svelte"github: stars: 78000 forks: 4100 contributors: 680 commits_last_month: 45 avg_issue_response_hours: 36 issue_resolution_rate: 0.72 releases_per_year: 8 active_maintainers: 5npm: weekly_downloads: 420000 version: "4.2.8" dependencies_count: 0 days_since_last_publish: 21community: stackoverflow_questions: 8500 job_postings: 1200 tutorials_count: 350 forum_members: 25000corporate_backing: type: "community_led" funding_millions: 0Output
ECOSYSTEM ANALYSIS: Svelte==========================
OVERALL HEALTH SCORE: 71.5/100
HEALTH SCORE BREAKDOWN----------------------| Category | Score | Assessment ||--------------------|-------|-------------------|| GitHub Health | 78.0 | Strong || npm Health | 72.0 | Good || Community Health | 58.0 | Moderate || Corporate Backing | 40.0 | Community-led || Maintenance Health | 75.0 | Active |
VIABILITY ASSESSMENT--------------------Overall: Good - Solid viability with minor concernsRisk Level: Low-Medium
Strengths:• Strong GitHub presence with active community• Active maintenance with responsive issue resolution• High npm adoption with stable releases
Risks:• Weak corporate backing - sustainability concerns• Smaller community - limited enterprise resources
RECOMMENDATION--------------Suitable for adoption - monitor corporate backing situation.Consider alternative with stronger backing for mission-critical enterprise apps.
KEY METRICS-----------GitHub: 78,000 stars, 680 contributors, 45 commits/monthnpm: 420,000 weekly downloads, v4.2.8Community: 8,500 SO questions, 1,200 job postingsMigration Assessment Example
Input
Assess migration from Angular.js (1.x) to React.Application: 50,000 lines of code, 200 components.Team: 6 developers, 2 have React experience.Timeline: Need completion within 8 months.Output
MIGRATION ASSESSMENT: Angular.js 1.x → React=============================================
COMPLEXITY SCORE: 7.8/10 (High)
COMPLEXITY BREAKDOWN--------------------| Factor | Score | Impact ||---------------------|-------|-------------|| Code Changes | 8/10 | 50K LOC || Architecture Impact | 9/10 | Complete || Data Migration | 5/10 | State only || Downtime Risk | 6/10 | Mitigatable |
EFFORT ESTIMATION-----------------| Phase | Hours | Duration ||--------------------------|--------|----------|| Planning & Prototyping | 240 | 3 weeks || Core Migration | 2,400 | 16 weeks || Testing & Validation | 480 | 5 weeks || Deployment & Monitoring | 160 | 2 weeks ||--------------------------|--------|----------|| TOTAL | 3,280 | 26 weeks |
Timeline Assessment: 26 weeks exceeds 8-month target (32 weeks)Recommendation: Feasible with buffer
RISK ASSESSMENT---------------Technical Risks:• High - Two-way binding to unidirectional data flow• Medium - Dependency injection to hooks/context• Medium - Performance regression during transition
Business Risks:• Medium - Feature freeze during migration• Low - Customer impact with phased approach
Team Risks:• High - 4 of 6 developers need React training• Medium - Learning curve affects velocity initially
MIGRATION STRATEGY------------------Recommended Approach: Strangler Fig Pattern
Phase 1 (Weeks 1-8): Strangler setup• Create React shell application• Set up micro-frontend routing• Migrate shared utilities
Phase 2 (Weeks 9-18): Component migration• Migrate components by feature area• Maintain Angular.js for untouched areas• Continuous integration testing
Phase 3 (Weeks 19-24): Completion• Migrate remaining components• Remove Angular.js dependencies• Performance optimization
Phase 4 (Weeks 25-26): Stabilization• Production deployment• Monitoring and fixesMulti-Technology Comparison
Input
Compare: React, Vue, Svelte, Angular for enterprise SaaS.Use case: Large team (20+ developers), complex state management.Generate comprehensive decision matrix.Output
MULTI-TECHNOLOGY COMPARISON: Enterprise SaaS Platform======================================================
RECOMMENDATION: ReactConfidence: 72% (Medium)Runner-up: Angular (close second for enterprise)
DECISION MATRIX---------------| Category | Wt | React | Vue | Svelte | Angular ||----------------------|------|-------|------|--------|---------|| Performance | 15% | 82 | 85 | 95 | 78 || Scalability | 15% | 90 | 82 | 75 | 92 || Developer Experience | 20% | 85 | 90 | 88 | 75 || Ecosystem | 15% | 95 | 80 | 65 | 88 || Learning Curve | 10% | 70 | 85 | 80 | 60 || Documentation | 10% | 90 | 85 | 75 | 92 || Community Support | 10% | 92 | 78 | 55 | 85 || Enterprise Readiness | 5% | 88 | 72 | 50 | 95 ||----------------------|------|-------|------|--------|---------|| WEIGHTED TOTAL | 100% | 86.3 | 83.1 | 76.2 | 83.0 |
FRAMEWORK PROFILES------------------React: Best for large ecosystem, hiring poolAngular: Best for enterprise structure, TypeScript-firstVue: Best for developer experience, gradual adoptionSvelte: Best for performance, smaller bundles
RECOMMENDATION RATIONALE------------------------For 20+ developer team with complex state management:
1. React (Recommended) • Largest talent pool for hiring • Extensive enterprise libraries (Redux, React Query) • Meta backing ensures long-term support • Most Stack Overflow resources
2. Angular (Strong Alternative) • Built-in structure for large teams • TypeScript-first reduces bugs • Comprehensive CLI and tooling • Google enterprise backing
3. Vue (Consider for DX) • Excellent documentation • Easier onboarding • Growing enterprise adoption • Consider if DX is top priority
4. Svelte (Not Recommended for This Use Case) • Smaller ecosystem for enterprise • Limited hiring pool • State management options less mature • Better for smaller teams/projects