In this module, you will learn to protect ASP.NET Core applications from common security threats and implement industry-standard security practices that safeguard user data and system integrity. You'll explore the most prevalent web vulnerabilities including SQL injection, cross-site scripting (XSS), and cross-site request forgery (CSRF), understanding how these attacks work and how to prevent them using ASP.NET Core's built-in security features. Through hands-on practice, you'll configure HTTPS and secure communication channels, implement SSL/TLS certificates, and apply security headers that protect data in transit. You'll work with deliberately vulnerable applications to identify and remediate security flaws, gaining practical experience in security testing and vulnerability assessment. You'll also implement security best practices in middleware components and integrate comprehensive API documentation using OpenAPI/Swagger with proper security configurations. By the end of this module, you'll be able to conduct security assessments, implement defense-in-depth strategies, and build applications that meet enterprise security standards while maintaining functionality and performance.

In this module, you will learn to build reliable, maintainable ASP.NET Core applications through comprehensive testing strategies that ensure code quality and prevent regressions. You'll explore the fundamentals of unit testing using xUnit framework, understanding how to structure test projects and write effective tests that follow the AAA (Arrange, Act, Assert) pattern. Through hands-on practice, you'll test controllers, services, and business logic components while learning to handle dependencies and error conditions appropriately. You'll implement integration tests using WebApplicationFactory to verify complete application workflows, including API endpoints, database operations, and middleware interactions. You'll also master test-driven development (TDD) principles, learning the Red-Green-Refactor cycle that leads to better code design and increased confidence in changes. You'll work with mocking frameworks to isolate components during testing and learn to balance test coverage with development efficiency. By the end of this module, you'll be able to implement comprehensive testing strategies that serve as both quality assurance and living documentation, enabling you to refactor and extend applications with confidence while maintaining high standards of code reliability.