diff --git a/examples/fibonacci.reid b/examples/fibonacci.reid
index 1b6b1db..9aad4c7 100644
--- a/examples/fibonacci.reid
+++ b/examples/fibonacci.reid
@@ -1,12 +1,13 @@
-// Main
-fn main() -> bool {
-    return 144 == fibonacci(0xc);
-}
-
-// Fibonacci
-fn fibonacci(value: u16) -> u16 {
-    if value <= 2 {
-        return 1;
-    }
-    fibonacci(value - 1) + fibonacci(value - 2)
-}
+a
+(
+    b
+)
+x
+(
+    (
+        c
+        xyz
+    )
+)
+(
+a
diff --git a/reid-lsp/package.json b/reid-lsp/package.json
index aa4d0ec..80723b1 100644
--- a/reid-lsp/package.json
+++ b/reid-lsp/package.json
@@ -43,11 +43,18 @@
           "description": "Traces the communication between VS Code and the language server."
         }
       }
-    }
+    },
+    "grammars": [
+      {
+        "language": "reid",
+        "scopeName": "source.reid",
+        "path": "./syntaxes/grammar.json"
+      }
+    ]
   },
   "scripts": {
     "vscode:prepublish": "pnpm run package",
-    "compile": "webpack",
+    "compile": "npx js-yaml syntaxes/grammar.yaml > syntaxes/grammar.json && webpack",
     "watch": "webpack --watch",
     "package": "webpack --mode production --devtool hidden-source-map",
     "compile-tests": "tsc -p . --outDir out",
@@ -65,6 +72,7 @@
     "@vscode/test-cli": "^0.0.11",
     "@vscode/test-electron": "^2.5.2",
     "eslint": "^9.25.1",
+    "js-yaml": "^4.1.0",
     "ts-loader": "^9.5.2",
     "typescript": "^5.8.3",
     "webpack": "^5.99.7",
diff --git a/reid-lsp/syntaxes/grammar.json b/reid-lsp/syntaxes/grammar.json
new file mode 100644
index 0000000..6478785
--- /dev/null
+++ b/reid-lsp/syntaxes/grammar.json
@@ -0,0 +1,44 @@
+{
+  "scopeName": "source.reid",
+  "patterns": [
+    {
+      "include": "#expression"
+    }
+  ],
+  "repository": {
+    "expression": {
+      "patterns": [
+        {
+          "include": "#letter"
+        },
+        {
+          "include": "#paren-expression"
+        }
+      ]
+    },
+    "letter": {
+      "match": "a|b|c",
+      "name": "keyword.letter"
+    },
+    "paren-expression": {
+      "begin": "\\(",
+      "end": "\\)",
+      "beginCaptures": {
+        "0": {
+          "name": "punctuation.paren.open"
+        }
+      },
+      "endCaptures": {
+        "0": {
+          "name": "punctuation.paren.close"
+        }
+      },
+      "name": "expression.group",
+      "patterns": [
+        {
+          "include": "#expression"
+        }
+      ]
+    }
+  }
+}
diff --git a/reid-lsp/syntaxes/grammar.yaml b/reid-lsp/syntaxes/grammar.yaml
new file mode 100644
index 0000000..493ac98
--- /dev/null
+++ b/reid-lsp/syntaxes/grammar.yaml
@@ -0,0 +1,23 @@
+scopeName: source.reid
+patterns:
+  - include: "#expression"
+repository:
+  expression:
+    patterns:
+      - include: "#letter"
+      - include: "#paren-expression"
+  letter:
+    match: "a|b|c"
+    name: "keyword.letter"
+  paren-expression:
+    begin: "\\("
+    end: "\\)"
+    beginCaptures:
+      0:
+        name: "punctuation.paren.open"
+    endCaptures:
+      0:
+        name: "punctuation.paren.close"
+    name: "expression.group"
+    patterns:
+      - include: "#expression"