diff --git a/grammar.js b/grammar.js
index 86d0dd6..d2c4652 100644
--- a/grammar.js
+++ b/grammar.js
@@ -118,6 +118,7 @@ module.exports = grammar({
       ),
     )),
 
+    // FIXME
     select_expression: ($) => seq(
       "select",
       "(",
@@ -127,6 +128,7 @@ module.exports = grammar({
       ")",
     ),
 
+    // FIXME
     select_value: ($) => seq(
       field("type", alias(
         choice("product_variable", "release_variable", "variant"),
@@ -137,6 +139,7 @@ module.exports = grammar({
       ")",
     ),
 
+    // FIXME
     soong_config_variable: ($) => seq(
       field("type", alias("soong_config_variable", $.selection_type)),
       "(",
@@ -151,6 +154,7 @@ module.exports = grammar({
       ")",
     ),
 
+    // FIXME should probably be hidden completely
     select_cases: ($) => seq(
       "{",
       optional(trailingCommaSeparated($.select_case)),
@@ -159,12 +163,14 @@ module.exports = grammar({
       "}",
     ),
 
+    // FIXME: Do I really need to account for default_case is being different?
     select_case: ($) => seq(
       field("pattern", $._string_literal),
       ":",
       field("value", $._case_value)
     ),
 
+    // FIXME
     default_case: ($) => seq(
       field("pattern", "default"),
       ":",
diff --git a/queries/highlights.scm b/queries/highlights.scm
index a28d844..fa87c49 100644
--- a/queries/highlights.scm
+++ b/queries/highlights.scm
@@ -49,6 +49,15 @@
     field: (identifier) @variable.member))
 ; }}}
 
+; Built-ins {{{
+[
+ (unset)
+ "default"
+] @variable.builtin
+
+(selection_type) @function.builtin
+; }}}
+
 ; Expressions {{{
 (map_expression
   (property
diff --git a/test/highlight/builtins.bp b/test/highlight/builtins.bp
new file mode 100644
index 0000000..cb5333f
--- /dev/null
+++ b/test/highlight/builtins.bp
@@ -0,0 +1,13 @@
+foo = select(soong_config_variable("my_namespace", "my_var"), {
+    //       ^ function.builtin
+    "foo": unset,
+    //     ^ variable.builtin
+    default: true,
+    // <- variable.builtin
+})
+
+/* Assigning to builtins is conveniently not allowed at runtime */
+unset = 12
+// <- variable.builtin
+default = 27
+// <- variable.builtin
diff --git a/test/highlight/select.bp b/test/highlight/select.bp
new file mode 100644
index 0000000..8bf3113
--- /dev/null
+++ b/test/highlight/select.bp
@@ -0,0 +1,5 @@
+foo = select(soong_config_variable("my_namespace", "my_var"), {
+    // ^ keyword.conditional
+    "foo": unset,
+    default: "bar",
+})