Express

1 Set NODE_ENV=production and disable error details

javascript

// Set in environment: NODE_ENV=production

// Error handler — don't leak stack traces
app.use((err, req, res, next) => {
  res.status(err.status || 500).json({
    error: process.env.NODE_ENV === 'production'
      ? 'Internal server error'
      : err.message,
  });
});

Django

1 Set DEBUG = False in production settings

python

# settings.py
DEBUG = False  # NEVER True in production
ALLOWED_HOSTS = ['yourdomain.com']

Laravel

1 Set APP_DEBUG=false in your .env

# .env
APP_DEBUG=false
APP_ENV=production

Rails

1 Ensure full error pages are disabled in production

ruby

# config/environments/production.rb
config.consider_all_requests_local = false

Spring Boot

1 Disable error details in production

properties

# application-production.properties
server.error.include-stacktrace=never
server.error.include-message=never

WordPress

1 Disable WP_DEBUG in production

php

// wp-config.php
define('WP_DEBUG', false);
define('WP_DEBUG_DISPLAY', false);

ASP.NET

1 Set ASPNETCORE_ENVIRONMENT=Production
2 Use the exception handler middleware

csharp

// Program.cs
if (!app.Environment.IsDevelopment())
{
    app.UseExceptionHandler("/error");
}

Flask

1 Set debug=False and disable the Werkzeug debugger

python

# app.py
app.run(debug=False)

# Or via environment
# FLASK_DEBUG=0

Turn off debug mode in production

Frameworks

Express

Django

Laravel

Rails

Spring Boot

WordPress

ASP.NET

Flask