Language support for ArchLang — a typed language for describing system architecture as text. Modules, interfaces, processes, labels, and diffs in one versioned source.

ArchLang preview panel

Features

Syntax highlighting for .arch and .archspace files.
Diagnostics on save and as you type — unknown types, missing required labels, broken references, malformed processes.
Go to Definition, Find References, Hover, Rename, Autocomplete for modules, interfaces, types, and labels.
Format on save — canonical indentation enforced by the language server.
Live diagram preview in a side panel — boots a local server bundled with the extension, renders the workspace as an interactive diagram.

Quick start

Install the extension.
Open a folder containing a package.archspace manifest and one or more .arch files.
Open any .arch file. The status bar shows an Arch Preview button — click it to open the live diagram.

Keyboard shortcut: Cmd+Shift+V (Ctrl+Shift+V on Linux/Windows) toggles the preview panel.

Commands (via the Command Palette):

ArchLang: Open Preview
ArchLang: Close Preview
ArchLang: Toggle Preview
ArchLang: Restart Preview Server
ArchLang: Restart Language Server

Requirements

None. The extension reuses VS Code's bundled Node.js runtime to run the preview server — you do not need Node installed on your system.

If you prefer a specific Node binary (older VS Code builds, custom forks, etc.), set archlang.nodePath in Settings.

Settings

Setting	Default	What it does
`archlang.preview.autoOpen`	`false`	Open the preview panel as soon as the first `.arch` file is opened.
`archlang.preview.openExternal`	`false`	Use the system browser instead of the in-editor webview.
`archlang.nodePath`	`""`	Override the Node binary used to run the preview server. Blank reuses VS Code's bundled Node.
`archlang.trace.server`	`off`	Trace LSP messages — `off`, `messages`, or `verbose`.