Plugins

Accent CMS supports a WebAssembly (WASM) plugin system built on Extism. Plugins are sandboxed modules that can extend the CMS without compromising the host process. Each plugin is a compiled .wasm file paired with a plugin.toml metadata file that declares which capabilities it provides.

The Capability Surface

Plugins can provide five types of capabilities:

Plugins communicate with the host over a simple, language-agnostic JSON protocol, so they can be written in any language with an Extism PDK – Rust, Go, JavaScript, AssemblyScript, C, and more.

Enabling Plugins

Plugins are disabled by default. Enable them in config.yaml:

plugins:
  enabled: true
  directory: ./plugins    # default location

When enabled is false (the default), no plugins are loaded and no WASM runtime overhead is incurred. The plugin system is also resilient by design: a missing directory, an invalid plugin.toml, or a runtime error never prevents the server from starting or serving content.

In This Chapter

• Structure and Metadata – the plugin directory layout and the plugin.toml file: required fields, hooks, filters, shortcodes, routes, and per-plugin configuration.
• Communication Protocol – the JSON contract between host and plugin for every hook, filter, route handler, and media hook.
• Writing a Plugin – a complete Rust walkthrough from project setup through build, install, and verify, plus notes on other languages.
• Media Hooks – the on_media_discover and on_media_process hooks for enriching media metadata and transforming processed images.
• Managing Plugins – the accent plugin CLI for listing, inspecting, installing, and removing plugins, plus hot reload and graceful error handling.
• Security – fuel limits, compilation caching, pre-compilation, API version compatibility, and opt-in filesystem access.
• Configuration Reference – the full config.yaml reference for the plugin system and where to go next.