Editor integration

Dune ships a Language Server (dune lsp) and a Zed extension.

What the language server provides

• Diagnostics — type errors plus @deprecated, @experimental, and @must_use warnings with precise source ranges.
• Completions — keywords, built-in attributes, local symbols, imported module members, and typed receiver methods.
• Hover — the signature, attributes, and doc-comment of a symbol, including symbols from other modules.
• Go-to-definition — jumps to a local declaration or into the module file for imported symbols, aliases, and from ... import symbols.
• Semantic highlighting — distinguishes functions, methods, types, generic parameters, constants, variables, fields, modules, literals, operators, and doc comments and attribute decorators. The server reports standard LSP token types and modifiers such as declaration, readonly, static, and defaultLibrary.

Any editor that speaks LSP can talk to dune lsp over stdio.

Zed extension

The Zed extension lives in editors/zed/. It provides tree-sitter syntax highlighting, a symbol outline, and wires up the dune lsp server. Semantic tokens from the language server refine symbol roles when the server is running; tree-sitter remains the lexical fallback while the server starts or is unavailable. The extension pins the tree-sitter grammar to a commit of this repository, so fallback highlighting always matches the language version.

To use it, install the extension as a Zed dev extension pointing at editors/zed/, and make sure the dune binary (which also serves dune lsp) is built and on your PATH. After pulling changes that touch the LSP, rebuild the dune binary so the editor picks up new behavior.