MANDATORY IMPORTANT MUST use TaskCreate to break ALL work into small tasks BEFORE starting. MANDATORY IMPORTANT MUST use AskUserQuestion at EVERY decision point — never assume user preferences. MANDATORY IMPORTANT MUST research top 3 options per stack layer, compare with evidence, present report with recommendation + confidence %.

External Memory: For complex or lengthy work (research, analysis, scan, review), write intermediate findings and final results to a report file in plans/reports/ — prevents context loss and serves as deliverable.

Evidence Gate: MANDATORY IMPORTANT MUST — every claim, finding, and recommendation requires file:line proof or traced evidence with confidence percentage (>80% to act, <80% must verify first).

Quick Summary

Goal: Research, analyze, and compare tech stack options for each layer of the system. Act as a solution architect — derive technical requirements from business analysis, research current market, produce detailed comparison report, and present options to user for decision.

Workflow:

• Load Business Context — Read business evaluation, domain model, refined PBI artifacts

• Derive Technical Requirements — Map business needs to technical constraints

• Research Per Layer — WebSearch top 3 options for each stack responsibility

• Deep Compare — Pros/cons matrix, benchmarks, community health, team fit

• Score & Rank — Weighted scoring across 8 criteria

• Generate Report — Structured comparison report with recommendation

• User Validation — Present findings, ask 5-8 questions, confirm choices

Key Rules:

• MANDATORY IMPORTANT MUST research minimum 3 options per stack layer

• MANDATORY IMPORTANT MUST include confidence % with evidence for every recommendation

• MANDATORY IMPORTANT MUST run user validation interview at end (never skip)

• All claims must cite sources (URL, benchmark, case study)

• Never recommend based on familiarity alone — evidence required

Be skeptical. Apply critical thinking, sequential thinking. Every claim needs traced proof, confidence percentages (Idea should be more than 80%).

Step 1: Load Business Context

Read artifacts from prior workflow steps (search in plans/ and team-artifacts/ ):

• Business evaluation report (viability, scale, constraints)

• Domain model / ERD (complexity, entity count, relationships)

• Refined PBI (acceptance criteria, scope)

• Discovery interview notes (team skills, budget, timeline)

Extract and summarize:

Signal Value Source

Expected users ... discovery interview

Domain complexity Low/Med/High domain model

Team skills ... discovery interview

Budget constraint ... business evaluation

Timeline ... business evaluation

Compliance needs ... business evaluation

Real-time needs Yes/No refined PBI

Integration complexity Low/Med/High domain model

Step 2: Derive Technical Requirements

Map business signals to technical requirements:

Business Signal Technical Requirement Priority

High user scale Horizontal scaling, connection pooling Must

Complex domain Strong type system, ORM with migrations Must

Real-time features WebSocket/SSE support, event-driven arch Must

Small team Low learning curve, good DX, batteries-included Should

Tight budget Open-source, low hosting cost Should

Compliance Audit trail, encryption, auth framework Must

MANDATORY IMPORTANT MUST validate derived requirements with user via AskUserQuestion before proceeding to research.

Step 3: Research Per Stack Layer

For EACH layer, research top 3 options using WebSearch (minimum 5 queries total):

Stack Layers to Evaluate

Layer Example Options Research Focus

Backend Framework .NET, Node.js, Python, Go, Java Performance, type safety, ecosystem

Frontend Framework Angular, React, Vue, Svelte DX, ecosystem, hiring, enterprise fit

Database PostgreSQL, MongoDB, SQL Server Scale, query complexity, cost

Messaging/Events RabbitMQ, Kafka, Redis Streams Throughput, reliability, complexity

Infrastructure Docker+K8s, Serverless, PaaS Cost, ops overhead, scaling

Auth Keycloak, Auth0, custom Cost, compliance, flexibility

WebSearch Queries (minimum 5 per layer)

"{option_A} vs {option_B} {current_year} comparison" "{option} enterprise production case studies" "{option} community size github stars" "{option} performance benchmarks {use_case}" "{option} security track record vulnerabilities"

Step 4: Deep Comparison Matrix

For EACH stack layer, produce a comparison table:

Criteria Option A Option B Option C Weight

Team Fit score + rationale ... ... High

Scalability score + rationale ... ... High

Time-to-Market score + rationale ... ... High

Ecosystem/Libs score + rationale ... ... Medium

Hiring Market score + rationale ... ... Medium

Cost (hosting) score + rationale ... ... Medium

Learning Curve score + rationale ... ... Medium

Community Health score + rationale ... ... Low

Scoring: 1-5 scale. Weight: High=3x, Medium=2x, Low=1x.

Per-Option Detail Block

For each option, document:

{Layer}: {Option Name}

Pros:

• {Pro 1} — {evidence/source}
• {Pro 2} — {evidence/source}
• {Pro 3} — {evidence/source}

Cons:

• {Con 1} — {evidence/source}
• {Con 2} — {evidence/source}

Best suited when: {conditions} Not suitable when: {conditions} Production examples: {2-3 real companies using this}

Step 5: Weighted Score & Ranking

Calculate weighted total per option per layer. Present ranking:

{Layer} Ranking

1. {Option A} — Score: {X}/100 — Confidence: {Y}%
2. {Option B} — Score: {X}/100 — Confidence: {Y}%
3. {Option C} — Score: {X}/100 — Confidence: {Y}%

Recommendation: {Option A} Why: {2-3 sentence rationale linking to team skills, scale, and constraints}

Step 6: Generate Report

Write report to {plan-dir}/research/tech-stack-comparison.md with:

• Executive summary (recommended full stack in 5 lines)

• Technical requirements table (from Step 2)

• Per-layer comparison matrices (from Step 4)

• Per-layer rankings with recommendations (from Step 5)

• Combined recommended stack diagram

• Risk assessment for recommended stack

• Alternative stack (second-best combo) for comparison

• Unresolved questions

Report must be <=200 lines. Use tables over prose.

Step 7: User Validation Interview

MANDATORY IMPORTANT MUST present findings and ask 5-8 questions via AskUserQuestion :

Required Questions

• Per-layer recommendation confirmation — "For {layer}, I recommend {option}. Agree?"

• Options: Agree (Recommended) | Prefer {option B} | Need more research

• Risk tolerance — "The recommended stack has {risk}. Acceptable?"

• Team readiness — "Team needs to learn {X}. Training plan needed?"

• Budget alignment — "Estimated infra cost: ${X}/month. Within budget?"

• Timeline fit — "This stack enables MVP in {X} months. Acceptable?"

Optional Deep-Dive Questions (pick 2-3 based on context)

• "Should we consider {emerging tech} for {layer}?"

• "Any compliance requirements I haven't captured?"

• "Preference for managed services vs self-hosted?"

• "Monorepo or polyrepo for this team size?"

After user confirms, update report with final decisions and mark as status: confirmed .

Output

{plan-dir}/research/tech-stack-comparison.md # Full comparison report {plan-dir}/phase-02-tech-stack.md # Final confirmed tech stack decisions

MANDATORY IMPORTANT MUST break work into small todo tasks using TaskCreate BEFORE starting. MANDATORY IMPORTANT MUST validate EVERY recommendation with user via AskUserQuestion — never auto-decide. MANDATORY IMPORTANT MUST include confidence % and evidence citations for all claims. MANDATORY IMPORTANT MUST add a final review todo task to verify work quality.

Next Steps

MANDATORY IMPORTANT MUST after completing this skill, use AskUserQuestion to recommend:

• "/architecture-design (Recommended)" — Design solution architecture with chosen tech stack

• "/plan" — If architecture already decided

• "Skip, continue manually" — user decides

Closing Reminders

MANDATORY IMPORTANT MUST break work into small todo tasks using TaskCreate BEFORE starting. MANDATORY IMPORTANT MUST validate decisions with user via AskUserQuestion — never auto-decide. MANDATORY IMPORTANT MUST add a final review todo task to verify work quality.