diff --git a/integration_tests/tuple_test.ucg b/integration_tests/tuple_test.ucg
index 847fd96..48f2c23 100644
--- a/integration_tests/tuple_test.ucg
+++ b/integration_tests/tuple_test.ucg
@@ -12,6 +12,7 @@ let nestedtpl = {
     },
     scalar = 1,
     list = [1, 2, 3, 4],
+    maybe_val = NULL,
 };
 
 assert |
@@ -23,6 +24,9 @@ assert |
 assert |
     nestedtpl.scalar == 1;
 |;
+assert |
+    nestedtpl.maybe_val == NULL;
+|;
 assert |
     nestedtpl.inner.field == "value";
 |;
@@ -46,6 +50,7 @@ let nestedcopy = nestedtpl{
         },
         field2 = 2,
     },
+    maybe_val = "some val",
 };
 
 let deepnestedcopy = nestedcopy{
@@ -65,4 +70,19 @@ assert |
 |;
 assert |
     deepnestedcopy.inner.inner.field4 == 4;
+|;
+assert |
+    deepnestedcopy.maybe_val == "some val";
+|;
+
+let base_maybe = {
+    real = "A real value",
+};
+
+let copy_maybe = base_maybe{
+    real = NULL,
+};
+
+assert |
+    copy_maybe.real == NULL;
 |;
\ No newline at end of file
diff --git a/src/build/mod.rs b/src/build/mod.rs
index 2c60a60..83aeac8 100644
--- a/src/build/mod.rs
+++ b/src/build/mod.rs
@@ -877,7 +877,10 @@ impl<'a> Builder<'a> {
                     // overriding field here.
                     // Ensure that the new type matches the old type.
                     let src_val = v.get().clone();
-                    if src_val.1.type_equal(&expr_result) {
+                    if src_val.1.type_equal(&expr_result)
+                        || src_val.1.is_empty()
+                        || expr_result.is_empty()
+                    {
                         v.insert((src_val.0, expr_result));
                     } else {
                         self.pop_val();