TypeScript brings type safety to JavaScript. Here are the best practices for production-ready code.

Type Safety

Always enable strict mode in your tsconfig.json to catch potential errors early. Use explicit types instead of relying on inference.

export const tokens = {
  colors: {
    primary: {
      50: "#eff6ff",
      500: "#3b82f6",
      900: "#1e3a8a",
    },
    neutral: {
      0: "#ffffff",
      100: "#f5f5f5",
      900: "#171717",
    },
  },
  spacing: {
    xs: "0.25rem",
    sm: "0.5rem",
    md: "1rem",
    lg: "1.5rem",
    xl: "2rem",
  },
  radii: {
    sm: "0.25rem",
    md: "0.5rem",
    lg: "1rem",
    full: "9999px",
  },
} as const;

Code Organization

Structure your types and interfaces logically. Keep type definitions close to where they're used or in dedicated type files.

Error Handling

Use discriminated unions and exhaustive type checking to handle errors safely throughout your application.

Testing

Write tests alongside your TypeScript code to ensure type safety translates to runtime correctness.