Coding Standards

// package.json
{
  "type": "module",
  "scripts": {
    "lint": "eslint . && prettier --check .",
    "typecheck": "tsc --noEmit"
  },
  "devDependencies": {
    "@acme/eslint-config": "^3.0.0",
    "typescript": "^5.6.0"
  }
}

// eslint.config.js (flat config)
import acme from "@acme/eslint-config/node-service";
 
export default [...acme];

// packages/eslint-config/node-service.js
import tseslint from "typescript-eslint";
import prettier from "eslint-config-prettier";
 
export default tseslint.config(
  ...tseslint.configs.strictTypeChecked,
  {
    rules: {
      "@typescript-eslint/no-floating-promises": "error",
      "@typescript-eslint/require-await": "off",
      "no-restricted-imports": ["error", {
        patterns: [{ group: ["../**/infrastructure/**"], message: "Use application ports" }],
      }],
    },
  },
  prettier,
);

{
  "compilerOptions": {
    "target": "ES2022",
    "module": "NodeNext",
    "moduleResolution": "NodeNext",
    "strict": true,
    "noUncheckedIndexedAccess": true,
    "skipLibCheck": true
  }
}

// .dependency-cruiser.cjs
module.exports = {
  forbidden: [
    {
      name: "no-infra-in-domain",
      from: { path: "^src/modules/[^/]+/domain" },
      to: { path: "express|fastify|@nestjs" },
    },
  ],
};

// Prefer
export async function getUser(id: string): Promise<User | null> { ... }
 
// Avoid
export function getUser(id: string): Promise<User | null> {
  return db.user.findUnique(...); // OK if eslint clean
}

// Use child logger with context
req.log.info({ userId, orderId, msg: "order_created" });
// Never
console.log("order created", user.email);

src/modules/orders/
  domain/
  application/
  infrastructure/