diff --git a/ts-rs/tests/issue-70.rs b/ts-rs/tests/issue-70.rs
new file mode 100644
index 000000000..a90bd4d92
--- /dev/null
+++ b/ts-rs/tests/issue-70.rs
@@ -0,0 +1,57 @@
+#![allow(unused)]
+
+use std::collections::HashMap;
+use ts_rs::TS;
+
+#[test]
+fn issue_70() {
+    type TypeAlias = HashMap<String, String>;
+
+    #[derive(TS)]
+    enum Enum {
+        A(TypeAlias),
+        B(HashMap<String, String>),
+    }
+
+    #[derive(TS)]
+    struct Struct {
+        a: TypeAlias,
+        b: HashMap<String, String>
+    }
+
+    assert_eq!(Enum::decl(), "type Enum = { \"A\": Record<string, string> } | { \"B\": Record<string, string> };");
+    assert_eq!(Struct::decl(), "type Struct = { a: Record<string, string>, b: Record<string, string>, };");
+}
+
+#[test]
+fn generic() {
+    type GenericAlias<A = String, B = String> = HashMap<(A, String), Vec<(B, i32)>>;
+
+    #[derive(TS)]
+    struct Container {
+        a: GenericAlias<Vec<i32>, Vec<String>>,
+        b: GenericAlias
+    }
+    assert_eq!(
+        Container::decl(),
+        "type Container = { \
+            a: Record<[Array<number>, string], Array<[Array<string>, number]>>, \
+            b: Record<[string, string], Array<[string, number]>>, \
+        };"
+    );
+
+    #[derive(TS)]
+    struct GenericContainer<A, B = i32> {
+        a: GenericAlias,
+        b: GenericAlias<A, B>,
+        c: GenericAlias<A, GenericAlias<A, B>>
+    }
+    assert_eq!(
+        GenericContainer::<(), ()>::decl(),
+        "type GenericContainer<A, B = number> = { \
+            a: Record<[string, string], Array<[string, number]>>, \
+            b: Record<[A, string], Array<[B, number]>>, \
+            c: Record<[A, string], Array<[Record<[A, string], Array<[B, number]>>, number]>>, \
+        };"
+    );
+}
\ No newline at end of file