TECHNICAL EXECUTION WORKFLOW & TECH STACK SELECTION

Document Type: Technical Specification & Development Plan
Project: [Your Project Name]
Owner: Technical Lead / CTO
Created: January 20, 2026
Status: Comprehensive Technical Reference

Executive Summary: Your Technical Foundation

This document provides a complete workflow for technical execution covering:

1. Tech Stack Selection Framework - How to choose languages, frameworks, databases, hosting
2. System Architecture Patterns - Which patterns suit your use case (microservices, monolith, serverless)
3. Development Workflow - Code organization, review process, testing, deployment
4. System Design & Performance - Scalability, reliability, security by design
5. Development Standards - Coding practices, documentation, technical debt management
6. CI/CD & Version Control - Git workflows, automated testing, deployment pipelines
7. Team & Execution - Agile methodologies, sprint cadence, communication

PART 1: TECH STACK SELECTION FRAMEWORK

Step 1: Define Your Constraints (START HERE)

Before choosing ANY technology, answer these questions:

Step 2: Make Architecture-Level Decisions (FOUNDATION)

Architecture Pattern Selection Matrix:

Decision: Which Pattern?

• Building distributed systems? → Microservices or Serverless (decoupled, scalable services)
• SaaS product? → Monolith initially, evolve to microservices at 10M users
• Real-time system? → Event-driven or serverless with WebSockets
• Compliance-heavy? → Layered architecture (clear separation of concerns)

Step 3: Technology Stack Decision Framework

Layer-by-Layer Selection Process:

Layer 1: LANGUAGE & RUNTIME

DECISION TREE FOR YOUR PROJECT:

Text Decision Tree (Alternative):

Your Tech Stack Selection

1. PRIMARY LANGUAGE?
   ├─ Web/API/SaaS: TypeScript + Node.js (default for 2026)
   ├─ Data-Heavy: Python + FastAPI + TypeScript bridge
   ├─ Enterprise: Java/Kotlin + Spring Boot
   └─ Systems: Go or Rust (infrastructure)

2. DATABASE?
   ├─ Relational (SQL): PostgreSQL (default, 95% of cases)
   ├─ NoSQL (unstructured): MongoDB (only if you have reason)
   ├─ Search/Vector DB: Elasticsearch or pgvector (PostgreSQL) (if needed)
   ├─ Cache: Redis (for sessions, rate limiting)
   └─ Data Warehouse: DuckDB or BigQuery (analytics)

3. HOSTING & INFRASTRUCTURE?
   ├─ Serverless: Vercel or Cloudflare (global, lowest ops)
   ├─ Regional: Render or Railway (simple, startup-friendly)
   ├─ Self-Managed: AWS, Azure, GCP (most control, complex)
   └─ Message Queue: RabbitMQ or Redis (if needed)

4. AUTHENTICATION?
   ├─ Build vs Buy: BUY (Clerk, Auth0, Supabase)
   └─ Never build auth from scratch

5. MONITORING & OBSERVABILITY?
   ├─ APM: Datadog or New Relic
   ├─ Error Tracking: Sentry
   ├─ Logs: Loggly or Papertrail
   └─ Metrics: Prometheus + Grafana

Step 4: Your Recommended Tech Stack (2026 Best Practice)

For SaaS/Web Product:

Frontend:
├─ React 18+ or Vue 3+ (TypeScript required)
├─ Next.js 14+ or SvelteKit (meta-framework)
├─ Tailwind CSS (styling)
├─ Zustand or Pinia (state management)
└─ Testing: Vitest + Playwright

Backend:
├─ Node.js 20+ LTS (runtime)
├─ TypeScript 5.2+ (language)
├─ Next.js API Routes or Express/Fastify (framework)
├─ Prisma or Drizzle (ORM)
├─ PostgreSQL 15+ (database)
├─ Redis (caching + sessions)
└─ Testing: Jest + Supertest

DevOps & Deployment:
├─ Docker (containerization)
├─ GitHub Actions (CI/CD)
├─ Vercel/Render (hosting)
├─ Terraform or Pulumi (IaC)
└─ Monitoring: Datadog + Sentry

Quality & Security:
├─ ESLint + Prettier (code quality)
├─ GitHub code scanning (dependencies)
├─ OWASP testing (security)
└─ SonarQube (code coverage)

For Enterprise/Java Project:

Core Stack:
├─ Java 17+ or Kotlin (language)
├─ Spring Boot (framework)
├─ Maven or Gradle (build tool)
└─ PostgreSQL or Oracle (database)

Integration:
├─ REST APIs (Spring Web)
├─ Message Queues (RabbitMQ, Kafka)
└─ Service Discovery (Consul, Eureka)

Infrastructure:
├─ Docker + Kubernetes (containerization)
├─ CI/CD (Jenkins, GitLab CI)
└─ Monitoring (Prometheus, Grafana)

For Data Processing Project:

Core Framework:
├─ Python 3.11+ (for data processing)
├─ FastAPI (web framework)
├─ TypeScript/Node.js (APIs)
├─ PostgreSQL + Redis (data storage)
└─ Elasticsearch (search/analytics)

Data Stack:
├─ Pandas + NumPy (data manipulation)
├─ Apache Spark (big data processing)
├─ Jupyter Notebooks (analysis)
└─ Airflow (workflow orchestration)

Infrastructure:
├─ Docker + Kubernetes (deployment)
├─ Redis (caching & queues)
└─ Data warehouses (if needed)

Step 5: Technology Selection Decision Checklist

Before committing to any technology, verify:

• Ecosystem: Mature libraries? Large community? Documentation available?
• Hiring: Can you hire developers in your market for this tech?
• Maintenance: Will this still be relevant in 3-5 years?
• Scaling: Can this handle 10x your current needs without rewrite?
• Cost: Cloud costs, license fees, developer hourly rates?
• Security: Is this proven secure? Regular updates? Known vulnerabilities?
• DevOps: Easy to deploy, monitor, debug? Good tooling?
• Team Fit: Does your team already know it or have capacity to learn?

PART 2: SYSTEM ARCHITECTURE DESIGN PATTERNS

Recommended Pattern: Layered Monolith with Event-Driven Async Tasks

Why this pattern for most projects:

• 80% of successful startups use this approach initially
• Fast to build, simple to deploy, easy to debug
• Scales to 10M+ users before architectural change needed
• Easy to hire for (team knows the pattern)

Architecture Diagram: Production-Ready Layered System

┌─────────────────────────────────────────────────────────────────┐
│                    CLIENT LAYER                                 │
│  ┌──────────────┐  ┌──────────────┐  ┌──────────────┐           │
│  │   Web App    │  │  Mobile App  │  │    CLI Tool  │           │
│  │  (React)     │  │   (React)    │  │   (Node.js)  │           │
│  └──────────────┘  └──────────────┘  └──────────────┘           │
└───────────┬──────────────────────┬──────────────────────────────┘
            │                      │
            ▼                      ▼
┌─────────────────────────────────────────────────────────────────┐
│                    API GATEWAY / CDN                            │
│  ┌─────────────────────────────────────────────────────────┐   │
│  │ Cloudflare / Vercel Edge Network                        │   │
│  │ ├─ Request routing                                       │   │
│  │ ├─ Rate limiting                                         │   │
│  │ ├─ DDoS protection                                       │   │
│  │ └─ Caching (static assets)                              │   │
│  └─────────────────────────────────────────────────────────┘   │
└──────────────┬──────────────────────────────────────────────────┘
               │
               ▼
┌─────────────────────────────────────────────────────────────────┐
│                    APPLICATION LAYER                           │
│  ┌───────────────────────────────────────────────────────┐    │
│  │  REST API / GraphQL Endpoint (Next.js or Express)    │    │
│  │  ├─ Authentication & Authorization                    │    │
│  │  ├─ Input validation (Zod/Joi)                        │    │
│  │  ├─ Rate limiting middleware                          │    │
│  │  └─ Error handling & logging                          │    │
│  └───────────────────────────────────────────────────────┘    │
└──────────┬──────────────────────────────────────────────────────┘
           │
   ┌───────┼───────┐
   │       │       │
   ▼       ▼       ▼
┌──────────────────────────────────────────────────────────────┐
│                    BUSINESS LOGIC LAYER                      │
│  ┌──────────────┐  ┌──────────────┐  ┌──────────────┐       │
│  │  User        │  │  Agent       │  │  Transaction │       │
│  │  Service     │  │  Service     │  │  Service     │       │
│  └──────────────┘  └──────────────┘  └──────────────┘       │
│  ┌──────────────┐  ┌──────────────┐                         │
│  │  Auth        │  │  Webhook     │                         │
│  │  Service     │  │  Service     │                         │
│  └──────────────┘  └──────────────┘                         │
└──────────┬──────────────────────────────────────────────────┘
           │
           ▼
┌──────────────────────────────────────────────────────────────┐
│                    DATA LAYER (ORM/DAL)                      │
│  ┌───────────────────────────────────────────────────────┐  │
│  │  Prisma ORM / Drizzle                                │  │
│  │  ├─ Type-safe database access                        │  │
│  │  ├─ Query builder                                    │  │
│  │  ├─ Migration management                             │  │
│  │  └─ Relationship loading (N+1 prevention)            │  │
│  └───────────────────────────────────────────────────────┘  │
└──────────┬──────────────────────────────────────────────────┘
           │
   ┌───────┼─────────┬──────────┐
   │       │         │          │
   ▼       ▼         ▼          ▼
┌────────────┐ ┌──────────┐ ┌────────┐ ┌──────────────┐
│PostgreSQL  │ │  Redis   │ │ Vector │ │Blockchain   │
│ Database   │ │ Cache &  │ │Database│ │RPC Provider │
│            │ │ Sessions │ │(pgvect)│ │(Alchemy)    │
└────────────┘ └──────────┘ └────────┘ └──────────────┘

Cross-Cutting Concerns (All Layers):

┌─────────────────────────────────────────┐
│  SECURITY & AUTHORIZATION               │
│  ├─ JWT tokens & refresh logic          │
│  ├─ Role-based access control (RBAC)    │
│  ├─ Rate limiting                       │
│  ├─ Input sanitization                  │
│  └─ Audit logging                       │
└─────────────────────────────────────────┘

┌─────────────────────────────────────────┐
│  OBSERVABILITY (Logging, Metrics, APM)  │
│  ├─ Structured logging (JSON)           │
│  ├─ Performance metrics (Prometheus)    │
│  ├─ Distributed tracing (OpenTelemetry)│
│  ├─ Error tracking (Sentry)             │
│  └─ Real-time dashboards (Datadog)      │
└─────────────────────────────────────────┘

┌─────────────────────────────────────────┐
│  ASYNC PROCESSING & EVENTS              │
│  ├─ Message queue (Bull, RabbitMQ)      │
│  ├─ Event publishing (Node.js EventEmit)│
│  ├─ Webhooks (outgoing events)          │
│  ├─ Scheduled tasks (node-cron)         │
│  └─ Dead letter queues (DLQ)            │
└─────────────────────────────────────────┘

┌─────────────────────────────────────────┐
│  CACHING STRATEGY                       │
│  ├─ HTTP caching (CDN, Browser)         │
│  ├─ Database query cache (Redis)        │
│  ├─ Session storage (Redis)             │
│  ├─ Rate limit tracking (Redis)         │
│  └─ Invalidation strategy               │
└─────────────────────────────────────────┘

Key Architecture Decisions (ADRs)

ADR-001: Monolith vs. Microservices Decision

Status: ACCEPTED

When Monolith is Right:

• Team < 10 engineers
• Single business domain (no clear service boundaries)
• <5M MAU (monthly active users)
• MVP or early-stage product
• Shared database is acceptable

When to Migrate to Microservices:

• Team > 15 engineers with clear team ownership
• Multiple independent domains (users, billing, agents, analytics)

• 10M MAU with complex scaling requirements

• Different parts need different tech stacks
• You've documented the seams clearly

Our Decision: Start monolithic, migrate to microservices only when pain becomes clear

ADR-002: REST vs. GraphQL

Status: ACCEPTED

Decision: REST API for MVP, GraphQL as optional addition

REST API Advantages:

• Simpler caching (HTTP-based)
• Better for mobile (less over-fetching)
• Industry standard
• Great tooling & documentation
• Easier to version

GraphQL Advantages:

• No over-fetching
• Single endpoint
• Great for complex queries
• Better developer experience

Recommendation: Start with REST. If clients constantly over-fetch or you need multiple device interfaces, add GraphQL layer without removing REST.

ADR-003: Database: PostgreSQL or MongoDB?

Status: ACCEPTED: PostgreSQL

Decision: PostgreSQL for 95% of cases in 2026

PostgreSQL Wins Because:

• ACID transactions (data integrity)
• Rich data types (JSON, arrays, custom types)
• pgvector extension (AI embeddings)
• Mature ecosystem
• Scales to billions of rows
• Better with ORMs (Prisma, Drizzle)
• Open-source & free

MongoDB Only If:

• Truly schema-less data (rare)
• You need massive horizontal scaling (>10B documents)
• Your data is naturally hierarchical with deep nesting

ORM Choice: Prisma (best DX) or Drizzle (most control)

ADR-004: Hosting: Serverless vs. Containers vs. Traditional VPS

Status: ACCEPTED

Decision Matrix:

Recommendation for Startups: Start with Vercel (global edge network) or Railway (cheap, regional). Migrate to AWS/GCP/Azure only when Costs require self-optimization.

PART 3: DEVELOPMENT WORKFLOW & STANDARDS

Code Organization (Project Structure)

For Next.js / Full-Stack Project:

project-root/
├── app/                          # Next.js app directory
│   ├── api/                      # API routes
│   │   ├── auth/
│   │   ├── agents/
│   │   ├── users/
│   │   └── webhooks/
│   ├── (auth)/                   # Route groups
│   │   ├── login/
│   │   └── signup/
│   ├── dashboard/                # Protected routes
│   ├── layout.tsx                # Root layout
│   └── page.tsx                  # Home page
│
├── src/
│   ├── components/               # Reusable React components
│   │   ├── common/               # (Header, Footer, etc.)
│   │   ├── features/             # Feature-specific components
│   │   └── ui/                   # UI library (Button, Modal, etc.)
│   │
│   ├── lib/                      # Utility functions
│   │   ├── auth.ts               # Authentication logic
│   │   ├── db.ts                 # Database client
│   │   ├── hooks.ts              # Custom React hooks
│   │   └── utils.ts              # Helper functions
│   │
│   ├── services/                 # Business logic
│   │   ├── agents.ts             # Agent service
│   │   ├── users.ts              # User service
│   │   ├── transactions.ts        # Transaction service
│   │   └── webhooks.ts           # Webhook service
│   │
│   ├── types/                    # TypeScript types & interfaces
│   │   ├── agent.ts
│   │   ├── user.ts
│   │   ├── api.ts                # API request/response types
│   │   └── database.ts           # Database models
│   │
│   ├── middleware/               # Express-style middlewares
│   │   ├── auth.ts
│   │   ├── validation.ts
│   │   └── errorHandler.ts
│   │
│   ├── constants/                # Configuration constants
│   │   ├── env.ts
│   │   ├── messages.ts
│   │   └── config.ts
│   │
│   └── styles/                   # Global styles
│       └── globals.css
│
├── prisma/                       # Database schema
│   ├── schema.prisma             # ORM schema definition
│   └── migrations/               # DB migration history
│
├── __tests__/                    # Test files (mirror src/ structure)
│   ├── unit/
│   ├── integration/
│   └── e2e/
│
├── .github/
│   └── workflows/                # CI/CD pipelines
│       ├── test.yml
│       ├── deploy.yml
│       └── security-scan.yml
│
├── .env.example                  # Environment variables template
├── tsconfig.json                 # TypeScript configuration
├── tailwind.config.js            # Tailwind CSS configuration
├── jest.config.js                # Testing configuration
├── eslint.config.js              # Linting configuration
├── prettier.config.js            # Code formatting
├── package.json                  # Dependencies
└── README.md                     # Project documentation

Coding Standards

TypeScript Configuration

{
  "compilerOptions": {
    "target": "ES2022",
    "lib": ["ES2022", "dom", "dom.iterable"],
    "module": "ESNext",
    "moduleResolution": "bundler",
    "strict": true,
    "noUncheckedIndexedAccess": true,
    "noImplicitAny": true,
    "noImplicitThis": true,
    "alwaysStrict": true,
    "exactOptionalPropertyTypes": true,
    "forceConsistentCasingInFileNames": true,
    "skipLibCheck": true,
    "resolveJsonModule": true,
    "allowJs": false,
    "checkJs": false
  }
}

Code Style & Formatting

ESLint + Prettier Configuration:

// .eslintrc.json
{
  "extends": ["next/core-web-vitals", "prettier"],
  "rules": {
    "no-console": ["warn", { "allow": ["warn", "error"] }],
    "prefer-const": "error",
    "no-var": "error",
    "@typescript-eslint/explicit-function-return-types": "error",
    "@typescript-eslint/no-unused-vars": "error",
    "eqeqeq": ["error", "always"]
  }
}

// .prettierrc
{
  "semi": true,
  "singleQuote": true,
  "tabWidth": 2,
  "trailingComma": "es5",
  "printWidth": 100
}

Code Organization Best Practices

1. Single Responsibility Principle

// ❌ BAD: Service does too much
class UserService {
  async createUser() { }
  async sendEmail() { }
  async logMetrics() { }
  async validatePayment() { }
}

// ✅ GOOD: Service focused on single domain
class UserService {
  async createUser() { }
  async updateUser() { }
  async deleteUser() { }
}

// Other concerns go to other services
class EmailService { }
class MetricsService { }
class PaymentService { }

2. Dependency Injection

// ❌ BAD: Hard-coded dependencies
class UserService {
  private db = new Database();
  async getUser(id: string) {
    return this.db.query('SELECT * FROM users WHERE id = ?', id);
  }
}

// ✅ GOOD: Dependencies injected
class UserService {
  constructor(private db: Database) {}
  async getUser(id: string) {
    return this.db.query('SELECT * FROM users WHERE id = ?', id);
  }
}

3. Type Safety with Zod (Runtime Validation)

import { z } from 'zod';

// Define schema
const CreateUserSchema = z.object({
  email: z.string().email(),
  name: z.string().min(1),
  age: z.number().int().positive(),
});

type CreateUserRequest = z.infer<typeof CreateUserSchema>;

// Validate at runtime
async function createUser(data: unknown) {
  const validated = CreateUserSchema.parse(data);
  // validated is now type-safe CreateUserRequest
}

Code Review Standards

Code Review Checklist (Pull Request Requirements):

## Code Review Checklist

### Functionality
- [ ] Code does what the ticket describes
- [ ] Handles edge cases (empty data, null values, errors)
- [ ] No regressions in existing functionality
- [ ] Tests added or updated
- [ ] Database migrations included (if applicable)

### Code Quality
- [ ] Follows project conventions (naming, structure)
- [ ] No console.logs left behind (except warn/error)
- [ ] No commented-out code blocks
- [ ] No hardcoded values (use environment variables)
- [ ] DRY principle (no duplicated code)
- [ ] Single responsibility (functions do one thing)

### Performance
- [ ] No N+1 queries (check database access patterns)
- [ ] No unnecessary loops or iterations
- [ ] Caching implemented where appropriate
- [ ] Large data structures handled efficiently

### Security
- [ ] User input validated and sanitized
- [ ] No secrets/API keys committed
- [ ] SQL injection prevented (using ORM/parameterized queries)
- [ ] CORS headers configured correctly
- [ ] Authentication/authorization checked

### Testing
- [ ] Unit tests added for business logic (min 80% coverage)
- [ ] Integration tests for API endpoints
- [ ] Tests are meaningful (not just coverage-padding)
- [ ] All tests pass locally and in CI

### Documentation
- [ ] Code comments explain WHY not WHAT
- [ ] API endpoints documented (request/response examples)
- [ ] Complex logic explained with inline comments
- [ ] README updated if applicable

### DevOps & Deployment
- [ ] .env.example updated with new variables
- [ ] Database migrations tested
- [ ] Backwards compatible (no breaking changes without version bump)
- [ ] Deployment instructions clear

Version Control (Git) Workflow

Branch Strategy: Git Flow

main (production)
│
├─ hotfix/fix-bug-x ──→ (PR to main + develop)
│
develop (staging)
│
├─ feature/new-feature ──→ (PR to develop)
├─ fix/bug-name ────────→ (PR to develop)
└─ refactor/update-x ───→ (PR to develop)

Commit Message Convention (Conventional Commits)

<type>(<scope>): <subject>

<body>

<footer>

---

Types:
- feat: new feature
- fix: bug fix
- docs: documentation
- style: code style (formatting)
- refactor: code refactoring
- test: adding tests
- chore: dependencies, build config
- perf: performance improvement

Examples:
feat(auth): add JWT refresh token rotation
fix(agents): prevent N+1 query in agent list endpoint
docs(api): update endpoint documentation
refactor(services): extract common logic to base class
test(users): add test for email validation

Testing Strategy

Testing Pyramid (% of Total Tests)

         /\
        /  \          E2E Tests: 5%
       /____\         (Critical user journeys)
      /      \
     /        \       Integration: 20%
    /__________\      (Service interactions, API endpoints)
   /            \
  /              \    Unit: 75%
 /________________\   (Functions, utilities, business logic)

Unit Test Example (Jest)

import { UserService } from './user.service';
import { Database } from './database';

describe('UserService', () => {
  let service: UserService;
  let db: jest.Mocked<Database>;

  beforeEach(() => {
    db = {
      query: jest.fn(),
    } as any;
    service = new UserService(db);
  });

  describe('createUser', () => {
    it('should create a user with valid input', async () => {
      const input = { email: 'test@example.com', name: 'Test' };
      db.query.mockResolvedValue({ id: '123', ...input });

      const result = await service.createUser(input);

      expect(result.id).toBe('123');
      expect(db.query).toHaveBeenCalledWith(
        expect.stringContaining('INSERT'),
        expect.objectContaining(input)
      );
    });

    it('should throw error for invalid email', async () => {
      const input = { email: 'invalid', name: 'Test' };

      await expect(service.createUser(input)).rejects.toThrow('Invalid email');
    });
  });
});

Integration Test Example (Supertest + Express)

import request from 'supertest';
import { app } from '../app';

describe('POST /api/users', () => {
  it('should create a user and return 201', async () => {
    const res = await request(app)
      .post('/api/users')
      .send({ email: 'test@example.com', name: 'Test' });

    expect(res.status).toBe(201);
    expect(res.body).toHaveProperty('id');
    expect(res.body.email).toBe('test@example.com');
  });

  it('should return 400 for duplicate email', async () => {
    await request(app)
      .post('/api/users')
      .send({ email: 'test@example.com', name: 'Test' });

    const res = await request(app)
      .post('/api/users')
      .send({ email: 'test@example.com', name: 'Test 2' });

    expect(res.status).toBe(400);
    expect(res.body.error).toContain('duplicate');
  });
});

PART 4: CI/CD PIPELINES & AUTOMATION

GitHub Actions Workflow: Test & Deploy

# .github/workflows/test-and-deploy.yml

name: Test and Deploy

on:
  push:
    branches: [main, develop]
  pull_request:
    branches: [develop]

jobs:
  test:
    name: Test
    runs-on: ubuntu-latest
    services:
      postgres:
        image: postgres:15
        env:
          POSTGRES_PASSWORD: postgres
        options: >-
          --health-cmd pg_isready
          --health-interval 10s
          --health-timeout 5s
          --health-retries 5

    steps:
      - name: Checkout code
        uses: actions/checkout@v4

      - name: Setup Node.js
        uses: actions/setup-node@v4
        with:
          node-version: '20'
          cache: 'npm'

      - name: Install dependencies
        run: npm ci

      - name: Lint code
        run: npm run lint

      - name: Check types
        run: npm run type-check

      - name: Run unit tests
        run: npm run test:unit
        env:
          NODE_ENV: test

      - name: Run integration tests
        run: npm run test:integration
        env:
          DATABASE_URL: postgres://postgres:postgres@localhost:5432/test_db

      - name: Upload coverage
        uses: codecov/codecov-action@v3
        with:
          files: ./coverage/coverage-final.json
          flags: unittests
          name: codecov-umbrella

  security:
    name: Security Scan
    runs-on: ubuntu-latest
    steps:
      - name: Checkout code
        uses: actions/checkout@v4

      - name: Setup Node.js
        uses: actions/setup-node@v4
        with:
          node-version: '20'
          cache: 'npm'

      - name: Run npm audit
        run: npm audit --audit-level=moderate

      - name: Run Snyk scan
        uses: snyk/actions/node@master
        env:
          SNYK_TOKEN: ${{ secrets.SNYK_TOKEN }}

  deploy:
    name: Deploy
    runs-on: ubuntu-latest
    needs: [test, security]
    if: github.event_name == 'push' && github.ref == 'refs/heads/main'
    steps:
      - name: Checkout code
        uses: actions/checkout@v4

      - name: Deploy to production
        env:
          VERCEL_TOKEN: ${{ secrets.VERCEL_TOKEN }}
        run: |
          npm run build
          npx vercel deploy --prod --token $VERCEL_TOKEN

Continuous Deployment Pipeline

┌─────────────────┐
│  Git Push       │
│  (Code commit)  │
└────────┬────────┘
         │
         ▼
┌─────────────────┐
│  GitHub Actions │
│  ├─ Lint        │
│  ├─ Type check  │
│  └─ Test        │
└────────┬────────┘
         │
    ┌────┴────┐
    │          │
    ▼          ▼
Success    Failure → Notify Slack
    │              Stop here
    │
    ▼
┌─────────────────┐
│  Build Docker   │
│  image & Push   │
│  to registry    │
└────────┬────────┘
         │
         ▼
┌─────────────────┐
│  Deploy to      │
│  Staging env    │
└────────┬────────┘
         │
         ▼
┌─────────────────┐
│  Smoke tests on │
│  staging        │
└────────┬────────┘
         │
    ┌────┴────┐
    │          │
    ▼          ▼
Success    Failure → Rollback
    │
    ▼
┌─────────────────┐
│  Deploy to Prod │
│  (blue/green)   │
└────────┬────────┘
         │
         ▼
┌─────────────────┐
│  Health checks  │
│  & monitoring   │
└─────────────────┘

PART 5: PERFORMANCE, SCALABILITY & RELIABILITY

Performance Optimization Checklist

Frontend Performance

• Code splitting (lazy load routes)
• Image optimization (next/image, WebP)
• Remove unused CSS (Tailwind purging)
• Minify & compress assets
• Service Worker for offline support
• Core Web Vitals tracked (LCP, FID, CLS)

Backend Performance

• Database query optimization (add indexes on foreign keys, frequently filtered columns)
• N+1 query prevention (eager loading)
• Caching strategy (Redis for hot data)
• Connection pooling (prevent exhausting DB connections)
• Pagination (never return all records)
• API response compression (gzip)

Database Performance

-- Frequently accessed queries should have indexes
CREATE INDEX idx_users_email ON users(email);
CREATE INDEX idx_agents_user_id ON agents(user_id);
CREATE INDEX idx_transactions_created_at ON transactions(created_at DESC);

-- Composite indexes for multi-column filters
CREATE INDEX idx_transactions_user_date ON transactions(user_id, created_at DESC);

Scalability Architecture

Horizontal Scaling Strategy

                    ┌─────────────────┐
                    │  Load Balancer  │
                    │  (nginx/ALB)    │
                    └────────┬────────┘
                             │
        ┌────────────────────┼────────────────────┐
        │                    │                    │
        ▼                    ▼                    ▼
    ┌────────┐          ┌────────┐          ┌────────┐
    │App     │          │App     │          │App     │
    │Server 1│          │Server 2│          │Server N│
    └────────┘          └────────┘          └────────┘
        │                    │                    │
        └────────────────────┼────────────────────┘
                             │
                             ▼
                    ┌─────────────────┐
                    │  PostgreSQL     │
                    │  (Primary +     │
                    │   Replicas)     │
                    └─────────────────┘
                             │
        ┌────────────────────┼────────────────────┐
        │                    │                    │
        ▼                    ▼                    ▼
    ┌────────┐          ┌────────┐          ┌────────┐
    │ Redis  │          │ Redis  │          │ Redis  │
    │Cache   │          │Cache   │          │Cache   │
    │(read)  │          │(read)  │          │(read)  │
    └────────┘          └────────┘          └────────┘

Database Replication Strategy

Primary (Write)
├─ Replica 1 (Read) - Real-time analytics
├─ Replica 2 (Read) - Search/indexing
└─ Replica 3 (Read) - Backup/reporting

Read queries load-balanced across replicas
Write queries → Primary only

Reliability & Fault Tolerance

Circuit Breaker Pattern (Prevent Cascading Failures)

import CircuitBreaker from 'opossum';

// Wrap external API calls
const breaker = new CircuitBreaker(
  async () => {
    return await externalAPI.call();
  },
  {
    timeout: 3000, // 3 seconds
    errorThresholdPercentage: 50, // Fail if 50% of calls error
    resetTimeout: 30000, // Try again after 30 seconds
  }
);

// If external service is down, return cached data
breaker.fallback(() => getCachedData());

// Usage in your service
async function getExternalData() {
  try {
    return await breaker.fire();
  } catch (error) {
    // Circuit is open, fallback is used
    return getCachedData();
  }
}

Retry Logic with Exponential Backoff

async function retryWithBackoff<T>(
  fn: () => Promise<T>,
  maxRetries: number = 3,
  baseDelay: number = 100
): Promise<T> {
  for (let i = 0; i < maxRetries; i++) {
    try {
      return await fn();
    } catch (error) {
      if (i === maxRetries - 1) throw error;

      // Exponential backoff: 100ms, 200ms, 400ms...
      const delay = baseDelay * Math.pow(2, i);
      await new Promise(resolve => setTimeout(resolve, delay));
    }
  }
}

// Usage
const data = await retryWithBackoff(() => externalAPI.call(), 3, 100);

PART 6: AGILE & TEAM EXECUTION

Sprint Structure (2-Week Sprints)

Monday - Sprint Planning (90 minutes)

Agenda:
├─ Review last sprint retrospective items
├─ Discuss upcoming features/priorities
├─ Estimate story points for each ticket
├─ Assign work to team members
└─ Commit to sprint goal

Daily - Standup (15 minutes)

Each engineer (2 minutes max):
├─ What did I complete?
├─ What am I working on?
└─ Any blockers?

No problem-solving in standup (follow-up after)

Wednesday - Midweek Sync (30 minutes)

├─ Check sprint progress (burndown)
├─ Identify risks early
├─ Re-prioritize if needed
└─ Unblock anyone stuck

Friday - Sprint Review & Retro (2 hours)

Sprint Review (60 minutes):
├─ Demo completed work to stakeholders
├─ Discuss what's next
└─ Gather feedback

Sprint Retrospective (60 minutes):
├─ What went well?
├─ What could improve?
├─ What will we change next sprint?
└─ Action items for next sprint

Story Point Estimation

Fibonacci Scale: 1, 2, 3, 5, 8, 13, 21

Velocity Tracking:

• Track story points completed per sprint
• After 3-4 sprints, you have baseline velocity
• Use velocity to plan how much work fits in next sprint

Technical Debt Management

Keep 10-20% of sprint capacity for technical debt:

Sprint Capacity: 40 points (example team)
├─ Feature work: 32 points (80%)
└─ Technical debt: 8 points (20%)

Technical debt backlog:
├─ Refactoring (extract common logic)
├─ Dependency updates (security patches)
├─ Performance improvements
├─ Test coverage gaps
└─ Documentation updates

When to Tackle Debt:

• ✅ After sprint completion (don't start mid-sprint)
• ✅ When you can't add features because of complexity
• ✅ Security vulnerabilities or performance issues
• ❌ Not during crunch periods (focus on shipping)

PART 7: DOCUMENTATION STANDARDS

Code Documentation

Self-Documenting Code

// ❌ BAD: Comments don't explain the WHY
function processUsers(u: User[]) {
  return u.filter(x => x.active).map(x => ({...x, lastSeen: new Date()}));
}

// ✅ GOOD: Clear naming + minimal comments
function getActiveUsersWithUpdatedTimestamp(users: User[]): UserDTO[] {
  return users
    .filter(user => user.isActive)
    .map(user => ({
      ...user,
      lastSeenAt: new Date(), // Track last activity for retention analysis
    }));
}

Function Documentation (JSDoc)

/**
 * Creates a new AI agent and deploys to blockchain
 *
 * @param config - Agent configuration with parameters and strategy
 * @param userId - Owner of the agent (for authorization)
 * @returns Deployed agent address on blockchain
 * @throws {ValidationError} If config is invalid
 * @throws {DeploymentError} If blockchain deployment fails
 *
 * @example
 * const agent = await createAndDeployAgent({
 *   name: 'Trading Bot',
 *   strategy: 'mean-reversion',
 * }, userId);
 */
async function createAndDeployAgent(
  config: AgentConfig,
  userId: string
): Promise<string> {
  // implementation
}

API Documentation

OpenAPI/Swagger Specification

openapi: 3.1.0
info:
  title: [Your Product Name] API
  version: 1.0.0

paths:
  /api/agents:
    post:
      summary: Create a new AI agent
      tags: [Agents]
      requestBody:
        required: true
        content:
          application/json:
            schema:
              type: object
              properties:
                name:
                  type: string
                  example: "Trading Bot"
                strategy:
                  type: string
                  enum: [mean-reversion, trend-following]
      responses:
        '201':
          description: Agent created successfully
          content:
            application/json:
              schema:
                type: object
                properties:
                  id:
                    type: string
                    example: "agent_123"
                  address:
                    type: string
                    example: "0x123..."
        '400':
          description: Invalid request
        '401':
          description: Unauthorized

Architecture Documentation

README Template

# Project Name

Brief description of what this project does.

## Quick Start

### Prerequisites
- Node.js 20+
- PostgreSQL 15+
- Redis 7+

### Installation

\`\`\`bash
git clone https://github.com/...
cd project
npm install
npm run dev
\`\`\`

### Environment Variables

Copy `.env.example` to `.env.local` and update values:

\`\`\`
DATABASE_URL=postgresql://...
REDIS_URL=redis://...
JWT_SECRET=your-secret-key
\`\`\`

## Architecture

[Include architecture diagram or description]

## Development

### Running Tests

\`\`\`bash
npm run test              # All tests
npm run test:unit        # Unit tests
npm run test:integration # Integration tests
npm run test:coverage    # With coverage report
\`\`\`

### Database Migrations

\`\`\`bash
npm run db:migrate       # Run migrations
npm run db:rollback      # Rollback last migration
\`\`\`

### Code Quality

\`\`\`bash
npm run lint             # Check linting
npm run format           # Auto-format code
npm run type-check       # TypeScript validation
\`\`\`

## Deployment

[Include deployment instructions for main branch + staging]

## Contributing

[Link to CONTRIBUTING.md]

SUMMARY: Your Technical Roadmap

Week 1-2: Finalize Tech Stack

• Review architecture decision in Section 4 of project plan
• Create ADRs (Architecture Decision Records) for each major choice
• Set up development environment (Docker, local DB, etc.)
• Configure CI/CD pipelines
• Create project scaffolding with linters, formatters, tests

Week 3-8: MVP Development

• Follow coding standards and code review process
• Write unit + integration tests (80%+ coverage minimum)
• Commit code regularly (small, focused PRs)
• Run security scans (npm audit, Snyk)
• Document code with JSDoc comments
• Track technical debt in backlog

Week 9-16: Scale & Optimize

• Monitor performance with APM tools
• Implement caching and database optimization
• Add load testing before launch
• Document architecture and runbooks
• Establish on-call rotation and incidents response
• Plan for horizontal scaling

Ongoing:

• Weekly standups + 2-week sprints
• Biweekly retrospectives
• Monthly technical debt allocation
• Quarterly architecture reviews

This is your technical blueprint. Reference it constantly. Update it as you learn.

Next: Complete Section 5-12 of your project plan using these technical foundations.