To be deprecated. The grammar's author is publishing an official HAProxy extension for the Zed registry, built on the same grammar with a more complete highlight query. This repo will be deprecated once that lands. Prefer theirs:
- Extension:
thochra/zed-haproxy-extension- Registry PR: zed-industries/extensions#5759
- Tracking issue: zed-industries/extensions#5761
A Zed extension that adds syntax highlighting for HAProxy configuration files (haproxy.cfg).
It wires up a tree-sitter HAProxy grammar and ships a highlights.scm query that maps its nodes to Zed's theme scopes: sections, directives, ACLs, conditionals, values, and comments.
Two community grammars exist: thochra/tree-sitter-haproxy and Ziehnert/tree-sitter-haproxy. This extension pins thochra, which parsed my config far more cleanly (3 unparsed lines vs 93).
This extension was assembled mostly from that existing tree-sitter grammar, with the Zed packaging and the highlight query generated with Claude Opus 4.8.
This is not a perfect or complete highlighter. It covers the common HAProxy config surface well, but the underlying grammar does not model every directive, and some advanced syntax is left unhighlighted rather than colored precisely. For example, http-request converter chains like req.hdr(host),field(1,:),lower degrade to plain text rather than breaking. It is good enough for day-to-day config reading, not a full HAProxy language server.
In Zed, run zed: install dev extension from the command palette and select this directory. Highlighting then applies to any haproxy.cfg.
The grammar is fetched by URL and pinned commit in extension.toml, so it is not vendored here and is not a git submodule (Zed reads the pin, not a submodule).
- Parsing bugs (a directive does not parse) belong upstream in
thochra/tree-sitter-haproxy. Once fixed there, bump thecommitinextension.tomlto pull the fix down. - Highlight and scope bugs (wrong color, missing mapping) belong here in
languages/haproxy/highlights.scm.