diff --git a/packages/language-server/src/languagePlugin.ts b/packages/language-server/src/languagePlugin.ts
index 8d04e7c..6360db7 100644
--- a/packages/language-server/src/languagePlugin.ts
+++ b/packages/language-server/src/languagePlugin.ts
@@ -9,7 +9,7 @@ import { URI } from "vscode-uri";
 
 export const analogLanguagePlugin: LanguagePlugin<URI> = {
   getLanguageId(uri) {
-    if (uri.path.endsWith(".analog") || uri.path.endsWith(".ag")) {
+    if (uri.path.endsWith(".analog") || uri.path.endsWith(".ag") || uri.path.endsWith(".agx")) {
       return "analog";
     }
   },
diff --git a/packages/vscode/package.json b/packages/vscode/package.json
index c7a70e6..fa2c243 100644
--- a/packages/vscode/package.json
+++ b/packages/vscode/package.json
@@ -32,7 +32,8 @@
         },
         "extensions": [
           ".analog",
-          ".ag"
+          ".ag",
+          ".agx"
         ]
       }
     ],