handlPlatform Docs

Build your toolchain one plugin at a time.

Universal plugins
One Plugin trait unifies libraries, targets, operations, rules, and options.
Learn more
Composable host
The Host is an empty composer that loads kits, resolves dependencies, and runs capabilities.
Build one
Kits and manifests
Curated, version-pinned kits make language toolchains reproducible and swappable.
Explore kits
Type-safe rules
contribute::
(rule) is checked at compile time, so a Format rule cannot reach a Linter.
See how it works
Plugin-defined options
Options are declared by the plugins that own them and resolved from kit, host, and user config.
Read about options
Multiple targets
Targets are plugins, so the same language can compile to native, wasm, JS, or an interpreter.
View architecture

Documentation structure

This documentation follows the Diátaxis framework, which separates documentation into four purposes:

Tutorials — step-by-step lessons for learning handl and the platform.
How-to guides — focused recipes for solving specific problems.
Explanations — background and conceptual understanding.
Reference — generated facts about functions, types, and APIs.