The birth of http4k: What started as a rewrite of a major scientific publisher's website evolved into the world's most testable web framework, now boasting millions of downloads monthly across its 180-module ecosystem. Learn how we built an entire HTTP toolkit from the ground up using pure functions and zero magic to deliver unprecedented testability.

http4k's unique design choices - born from real-world, high-scale demands - make it possible to test every aspect of your system with remarkable ease. By combining functional programming principles with a ruthless focus on testability, we've created a framework that makes building and testing web applications dramatically simpler than traditional approaches.

Throughout this talk, we'll demonstrate how http4k grew from a single project's needs into a comprehensive HTTP ecosystem, powering everything from high-performance APIs to complex web applications. You'll see firsthand how its pure-functional approach and extensive module system let you build exactly what you need, while keeping your applications remarkably simple to test and maintain.

Key focus areas:

- How a single project spawned the world's most testable web framework
- The evolution into a 180-module HTTP ecosystem
- How http4k also reimagines monolithic API client design
- A zero-magic approach to pure functional web development
- Practical demonstration of http4k's super- efficient design