beef-lsp-macos

A working Beef language server and VS Code extension for macOS.

Beef ships no editor integration of its own — upstream's IDE is Windows-only. This is a macOS build of a community language server, with the fixes needed to make it compile and run against the current Beef compiler.

completion · hover · go to definition · find references · rename
document symbols · signature help · semantic tokens · folding ranges
formatting · workspace symbols · diagnostics

Install

You need a Beef toolchain first (the server drives the real compiler):

git clone https://github.com/agorangetek/beef-macos && cd beef-macos
bash setup-beef-macos.sh

Then build the server from this repository and install the extension — see BUILDING.md. Short version:

# 1. put the server sources inside the Beef checkout and build them
cp -R src BeefProj.toml BeefSpace.toml <Beef>/BeefLsp/
cd <Beef>/IDE/dist && ./BeefBuild -workspace=<Beef>/BeefLsp -config=Release -platform=macOS

# 2. make the launcher visible to the editor
mkdir -p ~/bin && cp bin/BeefLsp ~/bin/ && chmod +x ~/bin/BeefLsp

# 3. install the extension
#    VS Code / VSCodium -> Extensions -> "..." -> Install from VSIX...
#    -> prebuilt/beeflang-0.1.1.vsix
#    then set "beeflang.serverPath": "~/bin/BeefLsp" (absolute path) in settings

Open a folder containing BeefSpace.toml, then a .bf file. Note that a folder must be open — the server needs a workspace root, and with only a file open it reports No workspace path given.

What's in here

Path
src/	The language server (24 Beef sources)
BeefProj.toml, BeefSpace.toml	Its Beef project/workspace, including the macOS build configs
vscode-extension/	The VS Code extension sources (TypeScript + Svelte settings UI)
prebuilt/beeflang-0.1.1.vsix	Ready-to-install extension
bin/BeefLsp	Launcher (wraps the server, which needs a Beef dist tree as its working directory)
patches/	Our changes as patches against the upstream fork, for upstreaming
tests/	Python LSP clients used to verify the server

Status

Verified on macOS 27.0 (Apple Silicon), Xcode 26, against the Beef commit pinned by beef-macos.

Server, driven by a Python LSP client:

Check	Result
initialize (VS Code-style capabilities)	PASS
rootUri only / workspaceFolders only / minimal capabilities	PASS
Diagnostics for a broken buffer, and clearing them when fixed	PASS — 4 diagnostics, then 0
documentSymbol	PASS — real symbols from the workspace
TCP transport (--port=N), which the extension uses	PASS
shutdown / exit	PASS

In VSCodium, end to end: the extension activates on onLanguage:bf, spawns the server, connects over TCP, and loads the workspace — confirmed from the editor's own Beef LSP output channel:

[INFO   ] Connected
[INFO   ] Loaded workspace at /tmp/beef_example
[INFO   ] Refreshing workspace

Known gaps

• Only the first entry of workspaceFolders is used — no multi-root support.
• URI decoding handles %3A and %20 only.
• Interactive features (completion/hover popups) are exercised at the protocol level, not clicked through in the editor.

Where this came from

The server is not ours: it is MineGame159's lsp branch, an alpha-stage community language server that had gone unmaintained since 2023. We ported it onto the current Beef compiler and fixed the macOS problems:

• API drift — three compiler-output overrides now take StringView; RemoveChild gained a parameter; the socket calls return payload Results, so == .Err became case .Err.
• rootUri support — it read only the deprecated rootPath, so editors that send just rootUri (Zed, Neovim, multi-root) loaded an empty workspace.
• A handshake stall — OnInitialize indexed args["capabilities"]["textDocument"]["semanticTokens"]["tokenTypes"], and this JSON type reads uninitialized memory when you index into a non-object. A client that did not advertise semanticTokens made the server go silent mid-handshake.
• A crash loop in the extension — a fixed 1-second wait before connecting with no retry (fail five times, then give up permanently), and a hardcoded port 5556 that stopped two windows coexisting.
• Noisy output — documentSymbol logged a warning per unrecognised navigation entry, flooding the output channel.
• beeflang.serverPath setting — macOS GUI apps do not inherit the shell PATH, so execFile("BeefLsp") could never find a launcher in ~/bin without it.

The socket layer also needed fixing, but that lives in Beef itself and is carried by beef-macos: IPv6 was broken on macOS (AF_INET6 was hardcoded to the Windows value, sockaddr lacked the BSD length byte, addrinfo used the glibc field order, and socket-option values came from Linux).

License and attribution

Two MIT-licensed works are combined here:

• Beef — Copyright © 2019 BeefyTech LLC — see LICENSE-Beef.txt
• The language server and VS Code extension — Copyright © 2022 MineGame159 — see LICENSE-vscode-extension.txt

Our changes are offered under the same terms.