Kotlin Application Security: From Basics to Advanced Techniques

Modern Kotlin applications face numerous threats: from traffic interception to code injection. The book "Kotlin Application Security" is a practical guide that will help you turn fragile code into a true fortress. Whether you are writing a mobile app for Android or a server-side application on Ktor, this book will give you the tools to protect data and users.

What is this book about?

The author systematically covers key aspects of Kotlin development security:

• Secure Code Basics: principles of least privilege, input validation, protection against OWASP Top 10 (SQL injection, XSS, CSRF).
• Cryptography in Kotlin: working with Bouncy Castle and Conscrypt libraries, AES/RSA encryption, password hashing (bcrypt, Argon2), secure key storage.
• Android Security: protecting SharedPreferences, using EncryptedSharedPreferences, working with KeyStore, protection against reverse engineering (ProGuard, R8, DexGuard).
• Network Security: configuring HTTPS, SSL Pinning, securing WebSocket connections, preventing MITM attacks.
• Backend Security: authentication (JWT, OAuth 2.0), REST API protection, rate limiting, logging without data leaks.
• Security Testing: static analysis (Detekt, SonarQube), dynamic testing, fuzzing, dependency auditing.

Who is this book for?

This book will be useful for:

• Kotlin developers (from Junior to Senior) who want to write secure code from the start.
• Android engineers seeking to protect applications from hacking and data leaks.
• Backend developers working with Ktor, Spring Boot, or Micronaut.
• DevOps and security engineers implementing secure development practices in Kotlin projects.

What will you learn?

After reading the book, you will be able to:

• Identify and eliminate common vulnerabilities in Kotlin applications.
• Implement encryption and secure storage of confidential data.
• Configure network communication security and authentication.
• Use static analysis tools and security testing.
• Design architecture following Secure by Design principles.

The book contains numerous code examples, checklists, and practical cases. All examples are relevant for Kotlin 1.9+ and compatible with modern versions of Android SDK and Ktor. Acquire the skills that will make your applications not only functional but truly secure.