VS Code

The Ku extension provides syntax highlighting, snippets, completion, formatting and compiler diagnostics for VS Code 1.85 or newer. Install the Ku CLI as well; the extension invokes it to check and run programs.

Install

Download your platform archive from the v0.0.18 Release, then extract it. Each archive contains ku-language-0.0.18.vsix alongside the CLI. The VSIX is inside the archive, rather than a separate Release asset.

In VS Code, open Extensions → … → Install from VSIX…, select that file, then run Developer: Reload Window. You can also install from the extracted directory:

code --install-extension ./ku-language-0.0.18.vsix

This installation uses the released VSIX directly; it does not require a Marketplace listing.

Select the Ku executable

Put ku on your PATH, or set Ku: Executable Path to its full path. For example, on macOS:

{
  "ku.executablePath": "/Users/you/tools/ku/ku"
}

On Windows, select ku.exe. Keep the other files from the extracted archive in their original relative locations. Run Ku: Show Version to check the executable the extension finds. The status bar also compares the CLI and extension versions.

Check and run a program

Save this as hello.ku:

fn main() {
    println("Hello, Ku!")
}

Use Ku: Check Current File, then Ku Run. Compiler diagnostics appear in Problems, and command output appears in the Ku output channel or terminal. Checking on open and save is enabled by default. Checking on every edit is optional through ku.checkOnChange.

Command	Purpose
Ku Run	Run the current .ku file with main()
Ku: Check Current File	Check syntax and types
Ku: Show IR	Inspect the intermediate representation
Ku: Build Current File	Build with the CLI’s default build path
Ku: Build Native C	Build with the native C backend
Ku: Package GC	Run the CLI package-cache cleanup command
Ku: Show Version	Show the resolved CLI version

Format with Format Document, or save with editor.formatOnSave enabled. The extension also supports ku.mod / ku.lock highlighting, local and imported definitions, an outline, import completion and quick fixes for selected diagnostics.

Completion and examples

Type http. for HTTP helpers, time. for date and clock operations, or json. for encoding and decoding. HTTP constructors are inserted as http.service() / http.server(). The http.server snippet creates a complete server; see the HTTP reference for its API and runnable examples.

Completion uses the extension’s built-in API list and selected receiver names. It does not infer every variable type or offer a complete compiler language server. A completion item does not establish support in every backend; use the corresponding library’s execution requirements.

Update

Install the VSIX from the version of Ku you use, then reload VS Code. The public v0.0.18 archive contains the extension shipped with that release. Later repository changes to completion and hover text take effect only after the extension is rebuilt and installed; they do not update an already downloaded VSIX automatically.