Pannonico for VS Code

Pannonico provides template completion, hover, definitions, and conservative diagnostics through a pinned Go/WASI language server. The extension discovers projects and owns VS Code and WASI lifecycle integration. Each language-server process owns one project's indexing and template semantics.

Pre-1.0 development notice: Pannonico is under active development. Until version 1.0.0, public contracts and user-visible behavior may change between releases. Expect breaking changes while the program and distribution model are being stabilized.

Requirements

• VS Code 1.100 or newer for the current VSIX
• WASM WASI Core
• A trusted, file-backed local, Remote-WSL, Remote-SSH, or Dev Container workspace
• A regular pannonico.yaml or .pannonico project marker, unless the project is selected manually

Codespaces, other remote providers, Restricted Mode, virtual workspaces, and VS Code for the Web are not supported.

Published VSIX 0.2.0 retains its historical VS Code 1.91 minimum. VSIX 0.3.3 and later require VS Code 1.100. This does not retroactively change the 0.2.0 contract.

Install

Install Pannonico from the Visual Studio Marketplace, or search for extension ID vx-rs.pannonico in VS Code. The required WASM WASI Core extension is declared as a dependency.

For an exact-byte fallback, download pannonico.vsix from the matching vx-rs/pannonico-vscode GitHub Release and install it with Extensions: Install from VSIX.... In maintained remote windows, install both Pannonico and WASI Core in the workspace extension group.

The extension and its VSIX contain no language-server WASM or GitHub credentials. The pinned module is downloaded from the immutable vx-rs/pannonico-lsp release when a project first needs it.

Language-server runtime

The extension downloads only when a detected project needs the pinned release and no valid cached module exists. It verifies the committed release target, byte size, SHA-256 digest, and WASM bytes before atomically installing the module in extension global storage. Each new project session revalidates the cached module's file type, size, SHA-256 digest, and WASM bytes before use.

Each marked project receives an isolated language-server process. Sibling and nested projects use separate sessions, and the deepest marked root owns a file. Creating or removing a marker reconciles only the affected project and its direct marked parent.

Use the Pannonico Output channel for release identity, project roots, session identity, timings, diagnostics, and lifecycle errors.

Completion

Template data completion in VS Code:

Built-in Pannonico metadata completion in a Vite template:

Commands

• Pannonico: Start Language Server
• Pannonico: Restart Language Server
• Pannonico: Restart All Language Servers
• Pannonico: Stop Language Servers
• Pannonico: Show Output

Start discovers all marked projects. When the window has no marker, it can select one configuration-free project folder manually. Restart targets the active editor's project when ownership is unambiguous; Restart All rediscovers the workspace.

Language features

Pannonico provides completion, hover, definitions, and definite saved-workspace diagnostics for project configuration, templates, layouts, partials, data, and the scalar-free .nav hierarchy. Navigation completion covers current, parent, and tree, including directory and page identities, page metadata, parent chains, and referenced-page frontmatter.

Inside {{template "shell/header"}}, completion offers discovered partial directories and names as soon as you type the opening quote. Hover explains the selected reference and its source. The same assistance covers layout selectors, get/has dotted keys, index exact keys, pageIs page names, t fallback languages, and date format tokens. Layout selectors work in page frontmatter and templates.defaultLayout configuration, including plain YAML scalars.

Markdown inline, fenced, and indented code remains literal documentation, so the extension does not show template completion, hover, definitions, or diagnostics inside it. The same applies inside an HTML wrapper marked with pannonico-verbatim. Language features resume in live source after the literal region.

Direct navigation links use tree.c for directories and tree.p for pages:

<a href="{{.nav.tree.p.index.url}}">Home</a>
<a href="{{.nav.tree.c.guides.p.install.url}}">Install</a>

VS Code's normal Problems collection and Explorer problem decorations show definite saved-file failures. Pannonico does not add a custom decoration provider. Unsaved template text takes precedence over saved direct-path findings until it is saved. YAML/JSON inputs also synchronize with the server. Configuration, data, frontmatter and template syntax errors appear even when the project cannot load. Hover an underline to read the compiler explanation; save the correction to clear it. CLI/MCP builds check rendered HTML and other execution-dependent errors that editor indexing does not evaluate.

Remote workspaces

Open the project through Remote-WSL, Remote-SSH, or Dev Containers. Confirm Pannonico and WASI Core are installed in the remote extension group and run in the workspace Extension Host. The selected workspace remains a file URI inside that host.

If startup reports an unsupported environment, confirm the intended remote is connected, the workspace is trusted and file-backed, and both extensions run on the remote side.

Current limits

• Trusted local, Remote-WSL, Remote-SSH, and Dev Container file workspaces only
• One WASI process per project root
• No general Go-template interpretation
• No remote-data fetch in the IDE path
• No object-key completion in a partial when its caller context is unknown; partial-name completion remains available
• No automatic LSP release discovery

License

Pannonico Free is available under either the PolyForm Noncommercial License 1.0.0 or the PolyForm Small Business License 1.0.0, at your option. Organizations whose use is not permitted by either license require a separate commercial Pannonico license. See the license chooser.

Support

Read the support guide before opening a Pannonico VS Code issue. Report suspected vulnerabilities through the shared private security process, not through a public issue.