Agent Skills: System & Environment Setup

System & Environment Setup

When to use this skill

• New project: Initial environment setup
• Team onboarding: Standardizing new developer environments
• Multiple services: Local execution of microservices
• Production replication: Testing production environment locally

Instructions

Step 1: Docker Compose Configuration

docker-compose.yml:

version: '3.8'

services:
  # Web Application
  web:
    build:
      context: .
      dockerfile: Dockerfile
    ports:
      - "3000:3000"
    environment:
      - NODE_ENV=development
      - DATABASE_URL=postgresql://postgres:password@db:5432/myapp
      - REDIS_URL=redis://redis:6379
    volumes:
      - .:/app
      - /app/node_modules
    depends_on:
      - db
      - redis
    command: npm run dev

  # PostgreSQL Database
  db:
    image: postgres:15-alpine
    environment:
      POSTGRES_USER: postgres
      POSTGRES_PASSWORD: password
      POSTGRES_DB: myapp
    ports:
      - "5432:5432"
    volumes:
      - postgres_data:/var/lib/postgresql/data
      - ./init.sql:/docker-entrypoint-initdb.d/init.sql

  # Redis Cache
  redis:
    image: redis:7-alpine
    ports:
      - "6379:6379"
    volumes:
      - redis_data:/data

  # Nginx (Reverse Proxy)
  nginx:
    image: nginx:alpine
    ports:
      - "80:80"
    volumes:
      - ./nginx.conf:/etc/nginx/nginx.conf:ro
    depends_on:
      - web

volumes:
  postgres_data:
  redis_data:

Usage:

# Start all services
docker-compose up -d

# View logs
docker-compose logs -f web

# Restart specific service only
docker-compose restart web

# Stop and remove
docker-compose down

# Remove including volumes
docker-compose down -v

Step 2: Environment Variable Management

.env.example:

# Application
NODE_ENV=development
PORT=3000
APP_URL=http://localhost:3000

# Database
DATABASE_URL=postgresql://postgres:password@localhost:5432/myapp
DATABASE_POOL_SIZE=10

# Redis
REDIS_URL=redis://localhost:6379

# JWT
ACCESS_TOKEN_SECRET=change-me-in-production-min-32-characters
REFRESH_TOKEN_SECRET=change-me-in-production-min-32-characters
TOKEN_EXPIRY=15m

# Email
SMTP_HOST=smtp.gmail.com
SMTP_PORT=587
SMTP_USER=your-email@gmail.com
SMTP_PASSWORD=your-app-password

# External APIs
STRIPE_SECRET_KEY=sk_test_xxx
STRIPE_PUBLISHABLE_KEY=pk_test_xxx
AWS_ACCESS_KEY_ID=AKIAXXXXXXX
AWS_SECRET_ACCESS_KEY=xxxxxxxx
AWS_REGION=us-east-1

.env (local only, add to gitignore):

# .gitignore
.env
.env.local
.env.*.local

Loading environment variables (Node.js):

import dotenv from 'dotenv';
import path from 'path';

// Load .env file
dotenv.config();

// Type-safe environment variables
interface Env {
  NODE_ENV: 'development' | 'production' | 'test';
  PORT: number;
  DATABASE_URL: string;
  REDIS_URL: string;
  ACCESS_TOKEN_SECRET: string;
}

function loadEnv(): Env {
  const required = ['DATABASE_URL', 'ACCESS_TOKEN_SECRET', 'REDIS_URL'];

  for (const key of required) {
    if (!process.env[key]) {
      throw new Error(`Missing required environment variable: ${key}`);
    }
  }

  return {
    NODE_ENV: (process.env.NODE_ENV as any) || 'development',
    PORT: parseInt(process.env.PORT || '3000'),
    DATABASE_URL: process.env.DATABASE_URL!,
    REDIS_URL: process.env.REDIS_URL!,
    ACCESS_TOKEN_SECRET: process.env.ACCESS_TOKEN_SECRET!
  };
}

export const env = loadEnv();

Step 3: Dev Container (VS Code)

.devcontainer/devcontainer.json:

{
  "name": "Node.js & PostgreSQL",
  "dockerComposeFile": "../docker-compose.yml",
  "service": "web",
  "workspaceFolder": "/app",

  "customizations": {
    "vscode": {
      "extensions": [
        "dbaeumer.vscode-eslint",
        "esbenp.prettier-vscode",
        "ms-azuretools.vscode-docker",
        "prisma.prisma"
      ],
      "settings": {
        "editor.formatOnSave": true,
        "editor.defaultFormatter": "esbenp.prettier-vscode",
        "eslint.validate": ["javascript", "typescript"]
      }
    }
  },

  "forwardPorts": [3000, 5432, 6379],

  "postCreateCommand": "npm install",

  "remoteUser": "node"
}

Step 4: Makefile (Convenience Commands)

Makefile:

.PHONY: help install dev build test clean docker-up docker-down migrate seed

help: ## Show this help
	@grep -E '^[a-zA-Z_-]+:.*?## .*$$' $(MAKEFILE_LIST) | sort | awk 'BEGIN {FS = ":.*?## "}; {printf "\033[36m%-20s\033[0m %s\n", $$1, $$2}'

install: ## Install dependencies
	npm install

dev: ## Start development server
	npm run dev

build: ## Build for production
	npm run build

test: ## Run tests
	npm test

test-watch: ## Run tests in watch mode
	npm test -- --watch

lint: ## Run linter
	npm run lint

lint-fix: ## Fix linting issues
	npm run lint -- --fix

docker-up: ## Start Docker services
	docker-compose up -d

docker-down: ## Stop Docker services
	docker-compose down

docker-logs: ## View Docker logs
	docker-compose logs -f

migrate: ## Run database migrations
	npm run migrate

migrate-create: ## Create new migration
	@read -p "Migration name: " name; \
	npm run migrate:create -- $$name

seed: ## Seed database
	npm run seed

clean: ## Clean build artifacts
	rm -rf dist node_modules coverage

reset: clean install ## Reset project (clean + install)

Usage:

make help         # List of commands
make install      # Install dependencies
make dev          # Start dev server
make docker-up    # Start Docker services

Step 5: Infrastructure as Code (Terraform)

main.tf (AWS example):

terraform {
  required_providers {
    aws = {
      source  = "hashicorp/aws"
      version = "~> 5.0"
    }
  }

  backend "s3" {
    bucket = "myapp-terraform-state"
    key    = "production/terraform.tfstate"
    region = "us-east-1"
  }
}

provider "aws" {
  region = var.aws_region
}

# VPC
resource "aws_vpc" "main" {
  cidr_block = "10.0.0.0/16"

  tags = {
    Name        = "${var.project_name}-vpc"
    Environment = var.environment
  }
}

# RDS (PostgreSQL)
resource "aws_db_instance" "postgres" {
  identifier           = "${var.project_name}-db"
  engine               = "postgres"
  engine_version       = "15.4"
  instance_class       = "db.t3.micro"
  allocated_storage    = 20
  storage_encrypted    = true

  db_name  = var.db_name
  username = var.db_username
  password = var.db_password

  vpc_security_group_ids = [aws_security_group.db.id]
  db_subnet_group_name   = aws_db_subnet_group.main.name

  backup_retention_period = 7
  skip_final_snapshot     = false
  final_snapshot_identifier = "${var.project_name}-final-snapshot"

  tags = {
    Name        = "${var.project_name}-db"
    Environment = var.environment
  }
}

# ECS (Container Service)
resource "aws_ecs_cluster" "main" {
  name = "${var.project_name}-cluster"

  setting {
    name  = "containerInsights"
    value = "enabled"
  }
}

# Load Balancer
resource "aws_lb" "main" {
  name               = "${var.project_name}-alb"
  internal           = false
  load_balancer_type = "application"
  security_groups    = [aws_security_group.alb.id]
  subnets            = aws_subnet.public[*].id
}

variables.tf:

variable "project_name" {
  description = "Project name"
  type        = string
  default     = "myapp"
}

variable "environment" {
  description = "Environment (dev, staging, production)"
  type        = string
}

variable "aws_region" {
  description = "AWS region"
  type        = string
  default     = "us-east-1"
}

variable "db_username" {
  description = "Database username"
  type        = string
  sensitive   = true
}

variable "db_password" {
  description = "Database password"
  type        = string
  sensitive   = true
}

Output format

Project Structure

project/
├── .devcontainer/
│   └── devcontainer.json
├── docker-compose.yml
├── Dockerfile
├── Makefile
├── .env.example
├── .gitignore
├── terraform/
│   ├── main.tf
│   ├── variables.tf
│   └── outputs.tf
└── README.md

Constraints

Mandatory Rules (MUST)

1. Provide .env.example: List of required environment variables
2. .gitignore: Never commit .env files
3. README.md: Document installation and running instructions

Prohibited (MUST NOT)

1. No committing secrets: Never commit .env, credentials files
2. No hardcoding: All configuration via environment variables

Best practices

1. Docker Compose: Use Docker Compose for local development
2. Volume Mount: Instantly reflects code changes
3. Health Checks: Verify service readiness

References

• Docker Compose
• Dev Containers
• Terraform

Metadata

Version

• Current Version: 1.0.0
• Last Updated: 2025-01-01
• Compatible Platforms: Claude, ChatGPT, Gemini

Related Skills

• deployment
• environment-setup

Tags

#environment-setup #Docker-Compose #dev-environment #IaC #Terraform #infrastructure

Examples

Example 1: Basic usage

Example 2: Advanced usage