Test-Driven Development for iOS

Test-Driven Development isn’t just about writing tests — it’s about building better software.
This course teaches you how to design, structure, and ship iOS apps using testing as a core engineering tool. You’ll learn how to write reliable, maintainable tests and how to use TDD to guide your architecture, catch bugs early, and refactor confidently.

Through a series of real, progressively complex app projects, you’ll gain hands-on experience with unit testing, UI testing, networking tests, CI/CD integration, and performance profiling in SwiftUI.

What You’ll Build & Learn

1. Foundations of TDD + Simple App Testing

We begin with a Savings Calculator app to establish the fundamentals of TDD:

• Writing meaningful unit tests for business logic
• Creating UI tests for user-driven flows
• Structuring small features with testability in mind
• Understanding red–green refactor and test-driven iteration

This module gives you the core mechanics you’ll use throughout the course.

2. Networking Tests with a Real Crypto App

Next, you’ll build a Crypto Tracker app and learn how to test code that relies on external data from an API:

• Writing tests for asynchronous and concurrent networking code
• Refactoring code from MV to MVVM to make it testable
• Mocking API calls and validating request/response handling
• Testing error paths, decoding, and edge cases
• Ensuring networking code is fully deterministic and repeatable

You’ll see exactly how testing influences architecture in real-world scenarios.

3. Advanced UI Testing: Full Onboarding Flow

We then move into complex UI testing by building and testing a multi-step onboarding experience:

• UI tests for navigation, state transitions, and conditional flows
• Testing forms, validation, buttons, and multi-screen logic
• Creating stable, resilient tests that survive UI changes
• Designing views and view models that support maintainable test suites

This module teaches you how to write UI tests with real engineering value.

4. CI/CD Integration with Xcode, GitHub Actions & Fastlane

With a full suite of tests in place, you’ll learn how to automate your workflow using CI/CD:

• Setting up test automation with GitHub Actions
• Running tests on every pull request or code change
• Generating build artifacts and preparing releases
• Understanding how CI enforces code quality on real teams
• Implement CD using Fastlane to upload builds to Test Flight & App Store

You’ll leave with a production-ready pipeline and a deeper understanding of how testing fits into modern development practices.

5. Performance Testing & Profiling SwiftUI

The course wraps with a deep dive into performance testing using Xcode Instruments:

• Using Xcode Instruments to profile SwiftUI app performance
• Measuring view refresh cycles and identifying unnecessary work
• Detecting performance bottlenecks in SwiftUI apps
• Using data-based insights to refactor for speed and efficiency
• Performance testing of real world algorithms

You’ll learn how professional teams diagnose and optimize iOS performance.

By the End of This Course, You Will…

• Understand how to apply TDD to real iOS apps
• Know how to write unit, UI, and networking tests that genuinely improve code quality
• Design features that are inherently more testable, intentional, and maintainable
• Confidently refactor existing codebases without fear
• Build and automate a full test pipeline with CI/CD
• Profile and measure SwiftUI performance like an advanced engineer
• Gain skills that stand out in interviews and on real production teams

Who This Course Is For

This course is designed for developers who want to:

• Level up their engineering skillset
• Build scalable apps with fewer bugs
• Understand how testing drives architecture
• Stand out in interviews or senior-level roles
• Improve confidence in refactoring and shipping code

Whether you're newer to testing or looking to deepen your skills, this course gives you the practical, hands-on experience needed to think and build like a professional iOS engineer.