Production Error Handling in Next.js: Typed Errors, Structured Logging, and Alerting

Most developers treat error handling as an afterthought — a try/catch wrapped around the happy path. Production-grade error handling is a system: typed errors, structured logging, user-facing messages, and automated alerting that catches issues before users report them. Typed Error Classes Define your error taxonomy upfront: // lib/errors.ts export class AppError extends Error { constructor( message: string, public readonly code: string, public readonly statusCode: number = 500, public readonly context?: Record<string, unknown> ) { super(message) this.name = this.constructor.name Error.captureStackTrace(this, this.constructor) } } export class NotFoundError extends AppError { constructor(resource: string, id: string) { super(`${resource} not found`, 'NOT_FOUND', 404, { resource, id }) } } export class ValidationError extends AppError { constructor(message: string, public readonly fields: Record<string, string[]>) { super(message, 'VALIDATION_ERROR', 422, { fields }) } } exp