Kotlin Application Security: From Basics to Advanced Techniques

In the modern world of software development, security is no longer an option — it is a mandatory requirement. The book "Kotlin Application Security" is a comprehensive guide that will help you protect your projects written in Kotlin from the most common and complex threats.

The author, Alexey Smirnov, a senior developer with 10 years of experience in cybersecurity, shares practical techniques for protecting both mobile Android applications and server-side solutions on the JVM. The book is built on the principle of "from simple to complex": you will start with basic security concepts and gradually move on to advanced auditing and protection techniques.

What you will learn from this book:

• Kotlin Security Basics: null-safety, typing, memory management, and how these language features help avoid vulnerabilities.
• Android Application Protection: secure key storage (Android Keystore), root access protection, code obfuscation, working with ProGuard/R8.
• Network Security: proper HTTPS handling, SSL Pinning, protection against Man-in-the-Middle attacks, secure use of Retrofit and Ktor.
• Data Encryption: symmetric (AES) and asymmetric (RSA) encryption, password hashing (bcrypt, Argon2), working with Kotlinx Serialization.
• Authentication and Authorization: JWT, OAuth 2.0, secure token handling, protection against CSRF and XSS attacks.
• Code Auditing: vulnerability detection using static analysis (Detekt, SpotBugs), fuzzing, penetration testing.
• Server-Side Security: protecting Spring Boot/Ktor applications, SQL injections, secure database interaction, logging without leaks.
• Advanced Topics: protection against reverse engineering, secure WebView handling, cryptography on the Kotlin Multiplatform platform.

Who this book is for:

• Android developers who want to protect their applications from hacking and data leaks.
• Kotlin backend developers (Spring Boot, Ktor) looking to strengthen the security of their APIs and servers.
• Students and beginner programmers who want to write secure code from the start.
• Team Leads and architects responsible for product security.

Each chapter contains practical code examples ready for use in real projects. You will learn not only how to fix vulnerabilities but also how to design architecture with security in mind from the early stages of development. Special attention is paid to typical Kotlin developer mistakes and ways to prevent them.

The book "Kotlin Application Security" will become your desktop reference that you will return to again and again. Whether you are creating a simple note-taking app or a complex financial system, the knowledge from this book will help you make your code truly secure.