FeaturedSecurity
Tale of the tape: Claude vs the http4k codebase
We put http4k in the ring with Claude Opus for four rounds, patching between each. Three new CVEs, an update to our first one, four advisories, ~40 hardenings. Here's …
16 Jun 2026
AI
http4k Mastery, On Tap for Your AI Coding Agent
http4k Agent Skills gives your AI coding agent the patterns, tricks, and hard-won knowledge of the http4k masters - regenerated with every release.
Apr 2026
AI
An MCP Server That Fits in a Tweet (and MCP Apps That Don't Need To)
http4k MCP SDK hits the 2025-11-25 spec, adds MCP Apps, OpenTelemetry, and a testing module - all with the testability you'd expect.
Mar 2026
AI
http4k AI - Because AI Without Tests is Just Expensive Random Number Generation
http4k AI brings deterministic, testable AI integrations to the JVM - comprehensive fakes, universal APIs, zero token costs in tests. Built on 8 years and 50+ million …
Jun 2025
AI
Simplifying MCP: http4k's Updated Authentication Model - Less Code, More Power
The http4k MCP SDK has been updated to support the latest Draft OAuth specification, enhancing security and flexibility in AI integrations.
May 2025
AI
AI
http4k MCP Has Landed: Build Your Own AI Agents with Zero Compromise on Testability!
The http4k MCP SDK brings AI integration capabilities to your http4k applications with the same testability-first approach you know and love.
Mar 2025
Releases
http4k v6: Still the most testable web toolkit on the planet!*
http4k v6 has landed! Discover the groundbreaking features we've packed into our most powerful release yet.
Feb 2025
Releases
Releases
Preview: http4k v6 and beyond! Introducing Enterprise Edition and Long-Term Support
There's a new major http4k release coming up! We're ready to announce the next chapter in the http4k ecosystem, including the introduction of the http4k Enterprise …
Dec 2024
Releases
http4k Platform v5 - New Servers, Loom, TracerBullet, OpenAI plugin SDK and more
There's a new major http4k release! Read about all the new things the team have been working on for http4k v5.
Jun 2023
Ecosystem
Add typesafe 12-factor configuration to http4k apps with Environments
An overview of how to configure http4k applications using the http4k-config module
Oct 2021
Announcements
Reassurance to http4k users regarding JCenter shutdown
Announcement regarding JCenter shutdown
Feb 2021
Releases
http4k v4 - 17 platforms and counting...
There's a new major http4k release! Read about all the new stuff the team have been working on for http4k v4.
Jan 2021
Ecosystem
http4k Toolbox - Guns for show, knives for a pro
An introduction to the http4k Toolbox website and CLI.
Nov 2020
Ecosystem
Ecosystem
Nanoservices - The Power of Composition
You thought that microservices were a thing? Pah! The powerful abstractions in the http4k toolkit allow you to write entire useful apps which fit in a Tweet.
Oct 2020
Announcements
A retrospective on http4k v3
In preparation for the upcoming release of v4, the http4k team thought we'd do a bit of a retrospective about all the things that have gone in the >260 releases of v3.
Sep 2020
Ecosystem
Documenting http4k APIs with OpenApi3
An overview of the OpenApi3 support available in the http4k library.
May 2019
Ecosystem
Websockets. But typesafe. And testable. Without the Server.
An overview of typesafe Websocket support in http4k
Dec 2017
Announcements
Announcements
Server as a Function. In Kotlin. Typesafe. Without the Server.
An overview of the Kotlin "Server as a Function" library, http4k
Nov 2017
