Kotlin Application Security: From Basics to Advanced Techniques

Modern development in Kotlin requires not only knowledge of the language but also a deep understanding of security principles. The book "Kotlin Application Security" is a comprehensive guide that will help you build secure applications in Kotlin for Android, backend (Ktor, Spring Boot), and multiplatform projects.

What is this book about?

The author systematically covers all key aspects of security: from basic concepts (encryption, hashing, key management) to complex topics (REST API security, injection protection, secure token storage). You will learn how to apply OWASP best practices, work with JWT, OAuth 2.0, SSL/TLS, and conduct code audits and penetration testing.

Who is this book for?

• Kotlin developers (Android, backend, Kotlin Multiplatform) who want to write secure code;
• DevOps engineers responsible for the security of CI/CD pipelines in Kotlin projects;
• Team Leads and architects looking to implement secure software development lifecycle (SSDLC) processes;
• Students and beginners learning Kotlin and interested in cybersecurity.

What will you learn by reading this book?

• How to set up secure storage for passwords, keys, and sensitive data (Android Keystore, EncryptedSharedPreferences);
• How to protect web APIs from attacks (SQL injection, XSS, CSRF, Path Traversal) using Ktor and Spring Security;
• How to properly implement authentication and authorization (JWT, OAuth 2.0, biometrics);
• How to use cryptography in Kotlin: symmetric/asymmetric encryption, digital signatures, integrity verification;
• How to integrate static code analyzers (Detekt, SpotBugs) and dynamic testing tools (OWASP ZAP, Burp Suite);
• How to protect Kotlin applications from reverse engineering (obfuscation, ProGuard, R8);
• How to ensure security in a multithreaded environment (Coroutines, Flow, Shared Flows).

Why should you read this book?

The book is written by a practicing security expert with many years of experience. All code examples are working and relevant to the latest versions of Kotlin (1.9+), Android SDK 34+, and popular frameworks. You will get not only theory but also ready-made solution templates for real projects. At the end of each chapter, there are security checklists and exercises to reinforce the material.

After reading, you will be able to independently conduct security audits of Kotlin applications, prevent vulnerabilities at the development stage, and confidently protect user data. This book will become your go-to reference for secure development in Kotlin.