diff --git a/src/fun/transform/encode_adts.rs b/src/fun/transform/encode_adts.rs
index 7a612f7a..4127f226 100644
--- a/src/fun/transform/encode_adts.rs
+++ b/src/fun/transform/encode_adts.rs
@@ -58,7 +58,7 @@ fn encode_ctr_num_scott<'a>(ctr_args: impl DoubleEndedIterator<Item = &'a Name>
   Term::rfold_lams(term, ctr_args.cloned().map(Some))
 }
 
-fn encode_num_scott_tag(tag : u32, ctr_name: &Name, source: Source) -> Definition {
+fn encode_num_scott_tag(tag: u32, ctr_name: &Name, source: Source) -> Definition {
   let tag_nam = Name::new(format!("{ctr_name}/tag"));
   let rules = vec![Rule { pats: vec![], body: Term::Num { val: Num::U24(tag) } }];
   Definition::new_gen(tag_nam.clone(), rules, source, true)
diff --git a/src/imports/book.rs b/src/imports/book.rs
index b491b85c..8ed6c0f5 100644
--- a/src/imports/book.rs
+++ b/src/imports/book.rs
@@ -200,6 +200,7 @@ impl ParseBook {
           name = Name::new(format!("__{}", name));
         }
 
+        adt.name = name.clone();
         adts_map.push((old_name, name.clone()));
       }
 
diff --git a/tests/golden_tests/import_system/import_type.bend b/tests/golden_tests/import_system/import_type.bend
index f2908c28..b79c33fa 100644
--- a/tests/golden_tests/import_system/import_type.bend
+++ b/tests/golden_tests/import_system/import_type.bend
@@ -1,6 +1,6 @@
 from lib/MyOption import (MyOption, MyOption/bind, MyOption/wrap)
 
-def main():
+def main() -> MyOption((u24, u24)):
   with MyOption:
     a <- MyOption/Some(1)
     b <- MyOption/Some(2)
diff --git a/tests/golden_tests/import_system/lib/MyOption.bend b/tests/golden_tests/import_system/lib/MyOption.bend
index c87f1700..f60de5fd 100644
--- a/tests/golden_tests/import_system/lib/MyOption.bend
+++ b/tests/golden_tests/import_system/lib/MyOption.bend
@@ -1,6 +1,8 @@
-type MyOption = (Some val) | (None)
+type MyOption(A):
+  Some { val: A }
+  None
 
-def MyOption/bind(val, nxt):
+def MyOption/bind(val: MyOption(A), nxt: (Id -> Id) -> A -> MyOption(B)) -> MyOption(B):
   match val:
     case MyOption/Some:
       nxt = undefer(nxt)
@@ -8,5 +10,5 @@ def MyOption/bind(val, nxt):
     case MyOption/None:
       return MyOption/None
 
-def MyOption/wrap(val):
+def MyOption/wrap(val: A) -> MyOption(A):
   return MyOption/Some(val)