pfftdammitchris

// analytics.d.ts - correct approach
declare namespace Analytics {
  interface Config {
    apiKey: string;
    endpoint: string;
  }
  
  function track(event: string, properties?: Record<string, unknown>): void;
  function identify(userId: string, traits?: Record<string, unknown>): void;
}

pfftdammitchris

// enhanced-websocket.d.ts
declare namespace EnhancedWS {
  interface ConnectionOptions {
    reconnect: boolean;
    maxRetries: number;
    timeout: number;
  }
  
  interface Message<T = unknown> {
    type: string;

pfftdammitchris

// dom-extensions.d.ts
declare namespace NodeJS {
  interface ProcessEnv {
    NEXT_PUBLIC_API_URL: string;
    NEXT_PUBLIC_FEATURE_FLAG: string;
  }
}

declare interface Window {
  gtag: (

pfftdammitchris

// express-augmentation.d.ts
import "express";

declare module "express" {
  namespace Express {
    interface Request {
      user?: {
        id: string;
        email: string;
        roles: string[];

pfftdammitchris

// winston-augmentation.d.ts
import "winston";

declare module "winston" {
  namespace winston {
    interface LoggerOptions {
      datadogApiKey?: string;
      datadogService?: string;
      enableCloudWatch?: boolean;
      cloudWatchGroup?: string;

pfftdammitchris

// legacy-validators.ts
namespace DataValidation {
  export namespace Email {
    export function isValid(email: string): boolean {
      return /^[^\s@]+@[^\s@]+\.[^\s@]+$/.test(email);
    }
    
    export function normalize(email: string): string {
      return email.toLowerCase().trim();
    }

pfftdammitchris

// validators/email.ts
export function isValid(email: string): boolean {
  return /^[^\s@]+@[^\s@]+\.[^\s@]+$/.test(email);
}

export function normalize(email: string): string {
  return email.toLowerCase().trim();
}

// validators/phone.ts

pfftdammitchris

// broken-mixed-pattern.ts - DO NOT DO THIS
import { logger } from "./logger";

namespace Utils {
  export function logError(message: string): void {
    // logger is undefined here at runtime
    logger.error(message);
  }
}

pfftdammitchris

// fixed-module-pattern.ts
import { logger } from "./logger";

export function logError(message: string): void {
  logger.error(message);
}

pfftdammitchris

interface Timestamped {
  timestamp: number;
}

function logWithTime<T extends Timestamped>(item: T): void {
  console.log(`[${new Date(item.timestamp).toISOString()}]`, item);
}

// Valid: object satisfies constraint
logWithTime({ timestamp: Date.now(), message: "Event" });