diff --git a/.helix/config.toml b/.helix/config.toml
index 07545b2..8b13789 100644
--- a/.helix/config.toml
+++ b/.helix/config.toml
@@ -1,2 +1 @@
-[editor]
-workspace-lsp-roots = ["jongline"]
+
diff --git a/.helix/languages.toml b/.helix/languages.toml
new file mode 100644
index 0000000..a35a590
--- /dev/null
+++ b/.helix/languages.toml
@@ -0,0 +1,6 @@
+[language-server.lspmux]
+command = "lspmux"
+
+[[language]]
+name = "rust"
+language-servers = ["lspmux"]
diff --git a/devenv.nix b/devenv.nix
index 89cd3ec..e1f7c55 100644
--- a/devenv.nix
+++ b/devenv.nix
@@ -4,6 +4,7 @@
     ...
 }: rec {
     # https://devenv.sh/processes/
+    processes.lspmux.exec = "lspmux server";
     processes.spacetimedb_start.exec = "spacetime start";
     processes.spacetimedb_generate_bindings = {
         exec = "spacetime dev --module-bindings-path jong/src/stdb jongline --delete-data=always";
@@ -17,7 +18,7 @@
 
     # https://devenv.sh/packages/
     packages = with pkgs; [
-        # process-compose
+        lspmux
         pkg-config
 
         # spacetimedb