Plugin system

Plugin system

Syrinx is a browser first, but its reason to exist is that code (Forge), notes (Notes) and the owner's business software (Fledge) live inside it as plugins that open as tabs and share one palette and one search. Nothing of the plugin system is built yet. This page explains the decision that shapes it and the order the work will happen in. The work itself is tracked in issues, linked below.

The 2026-10-15 decision

On 2026-10-15 the owner decided (recorded in docs/decisions.md):

Plugins are built from a template repository, each in its own repository, as sandboxed WebAssembly loaded at run time; no plugin work starts until Plan 1 closes (changes D17 and D34).

The owner wants a plugin template made first, then Forge, Notes and Fledge each built from it, the way Obsidian's sample-plugin template and Zed's extensions work. The decision has four parts.

• Repositories. A template repository on GitHub, marked as a template, and one repository per plugin made from it. The owner creates the repositories; agents prepare their contents. A template folder inside this repository was rejected, as were the crates/plugin-* workspace crates the earlier plans describe.
• Form. Each plugin is Rust compiled to WebAssembly (WASM), a portable bytecode that Syrinx runs inside a sandbox, so a module can touch nothing outside itself except through functions the host gives it. This is the Zed model. The functions and the values that cross them will be described in WIT (WebAssembly Interface Types), so host and plugin are generated from one definition.
• Host capabilities. A plugin reaches files, git, processes and the network only through host functions its manifest asks for and the owner grants, the way Chrome extensions declare permissions. Its interface is HTML and JavaScript inside Syrinx's own local web view, as Notes and Forge already planned for CodeMirror (D28), never a page web view. State stays in Rust, in the plugin's WASM module and in Syrinx's core.
• What changes. D17's sandbox is no longer deferred until a third party writes a plugin: the built-in plugins use it from the start. D34's "Plugin trait" becomes a WIT interface and host; Plan 2 otherwise stays thin.

The rejected alternatives, and why:

• Compiling the built-in plugins into syrinx.exe. Every plugin release would need a Syrinx release, which defeats separate repositories.
• Obsidian-style JavaScript plugins. No sandbox, and state would live outside Rust.
• Native DLLs. No sandbox, and Rust has no stable binary interface.

The owner chose this knowing its cost: Forge needs the host to provide real capabilities (terminals, git, language servers, Tree-sitter), as Zed's host does.

The order of work

The decision fixes the order. After Plan 1 closes, which is its last slice, the owner's one-week daily-driver acceptance: first the plugin interface and host, then the template, then each plugin. Starting the interface and template before Plan 1 closes was rejected. On 2026-10-16 the owner allowed one exception: the research note on the WASM runtime may start now.

1. #26, the research note. It compares the WASM runtime and interface choices (for example wasmtime and the component model, their licences and maintenance), designs the host capabilities and measures start-up and memory cost against D6. It is reviewed with the owner before Plan 2's slices are rewritten. It can start now.
2. #25 Epic: Plugin runtime: the rewrite of the Plan 2–4 slice boundaries and AGENTS.md's plugin rules for WASM (#27), the interface, registration, lifecycle and scoped storage (#28), plugin commands with forms in the palette and plugin tabs (#29), the template repository's contents (#30), and a plan for a customisable Home page with widgets (#31).
3. #32 Epic: Fledge plugin: the first plugin built from the template, a "New lead" form in the palette that works against a stand-in client. Fledge is reached only through a client interface, and the real client waits for Fledge's own Stage C (D24). The owner's acceptance of Plan 2 here unblocks Notes.
4. #35 Epic: Notes plugin: local Markdown files, wikilinks, backlinks, typed properties and a table view.
5. #42 Epic: Forge plugin: a project, editor and syntax highlighting, a terminal, git, language servers, tasks and split editors.

Background

The earlier comparison of plugin designs (a Rust trait, dynamic libraries, WebAssembly and out-of-process plugins, and what Zed and Lapce do) is Background 03. It predates the 2026-10-15 decision and recommended a statically registered Rust trait, which that decision replaced. The editor, syntax and language-server research for Notes and Forge is Background 04, and Fledge's API surface is Background 05.