diff --git a/CHANGELOG.md b/CHANGELOG.md
index 19ff7b2..0004ae5 100644
--- a/CHANGELOG.md
+++ b/CHANGELOG.md
@@ -1,3 +1,9 @@
+# [0.4.0] - 2024-03-21
+
+- Fix logic bug in `scale_typegen::utils::ensure_unique_type_paths`.
+
+- You can now specify a custom path to the `alloc` crate in the settings. It is used for type paths that are typically in the rust prelude or in the `std` library, like `Vec`, `Box` and `String`. This gives you the option to use the generated code in a `no_std` environment.
+
 # [0.3.0] - 2024-03-19
 
 - When generating rust code with `TypeGenerator::gerate_types_mod` we now validate that no type 
diff --git a/Cargo.lock b/Cargo.lock
index aa7c308..7e8678e 100644
--- a/Cargo.lock
+++ b/Cargo.lock
@@ -421,7 +421,7 @@ dependencies = [
 
 [[package]]
 name = "scale-typegen"
-version = "0.3.0"
+version = "0.4.0"
 dependencies = [
  "bitvec",
  "frame-metadata 16.0.0",
@@ -439,7 +439,7 @@ dependencies = [
 
 [[package]]
 name = "scale-typegen-description"
-version = "0.3.0"
+version = "0.4.0"
 dependencies = [
  "anyhow",
  "indoc",
diff --git a/Cargo.toml b/Cargo.toml
index d3b54b9..68fa80c 100644
--- a/Cargo.toml
+++ b/Cargo.toml
@@ -6,7 +6,7 @@ resolver = "2"
 [workspace.package]
 authors = ["Parity Technologies <admin@parity.io>"]
 edition = "2021"
-version = "0.3.0"
+version = "0.4.0"
 rust-version = "1.70.0"
 license = "Apache-2.0 OR GPL-3.0"
 repository = "https://github.com/paritytech/scale-typegen"
@@ -15,8 +15,8 @@ homepage = "https://www.parity.io/"
 
 [workspace.dependencies]
 
-scale-typegen-description = { version = "0.3.0", path = "description" }
-scale-typegen = { version = "0.3.0", path = "typegen" }
+scale-typegen-description = { version = "0.4.0", path = "description" }
+scale-typegen = { version = "0.4.0", path = "typegen" }
 
 # external dependencies
 parity-scale-codec = { version = "3.6.5", features = ["derive"] }
diff --git a/typegen/src/utils.rs b/typegen/src/utils.rs
index 421635a..8b14bfc 100644
--- a/typegen/src/utils.rs
+++ b/typegen/src/utils.rs
@@ -34,7 +34,7 @@ pub fn ensure_unique_type_paths(types: &mut PortableRegistry) {
             let ty_id_b = group[0]; // all types in group are same shape; just check any one of them.
             let ty_b = types.resolve(ty_id_b).expect("ty exists");
             if types_equal_extended_to_params(&ty.ty, ty_b) {
-                group.push(ty_id_b);
+                group.push(ty.id);
                 added_to_existing_group = true;
                 break;
             }
@@ -166,3 +166,68 @@ pub(crate) fn types_equal_extended_to_params(
         _ => false,
     }
 }
+
+#[cfg(test)]
+mod tests {
+    use scale_info::{meta_type, Path, PortableRegistry};
+
+    use crate::utils::ensure_unique_type_paths;
+
+    #[test]
+    fn ensure_unique_type_paths_test() {
+        macro_rules! foo {
+            ($ty:ident, $prim:ident ) => {
+                struct $ty;
+                impl scale_info::TypeInfo for $ty {
+                    type Identity = Self;
+                    fn type_info() -> scale_info::Type {
+                        scale_info::Type {
+                            path: Path::new("Foo", "my::module"),
+                            type_params: vec![],
+                            type_def: scale_info::TypeDef::Primitive(
+                                scale_info::TypeDefPrimitive::$prim,
+                            ),
+                            docs: vec![],
+                        }
+                    }
+                }
+            };
+        }
+
+        foo!(Foo1, Bool);
+        foo!(Foo2, Bool);
+        foo!(Foo3, U32);
+        foo!(Foo4, U128);
+        foo!(Foo5, U128);
+        foo!(Foo6, U128);
+
+        let mut registry = scale_info::Registry::new();
+        let id_1 = registry.register_type(&meta_type::<Foo1>()).id;
+        let id_2 = registry.register_type(&meta_type::<Foo2>()).id;
+        let id_3 = registry.register_type(&meta_type::<Foo3>()).id;
+        let id_4 = registry.register_type(&meta_type::<Foo4>()).id;
+        let id_5 = registry.register_type(&meta_type::<Foo5>()).id;
+        let id_6 = registry.register_type(&meta_type::<Foo6>()).id;
+        let mut registry = PortableRegistry::from(registry);
+
+        // before:
+        let ident = |id: u32| registry.resolve(id).unwrap().path.ident().unwrap();
+        assert_eq!(ident(id_1), "Foo");
+        assert_eq!(ident(id_2), "Foo");
+        assert_eq!(ident(id_3), "Foo");
+        assert_eq!(ident(id_4), "Foo");
+        assert_eq!(ident(id_5), "Foo");
+        assert_eq!(ident(id_6), "Foo");
+
+        // after:
+        ensure_unique_type_paths(&mut registry);
+
+        let ident = |id: u32| registry.resolve(id).unwrap().path.ident().unwrap();
+        assert_eq!(ident(id_1), "Foo1");
+        assert_eq!(ident(id_2), "Foo1");
+        assert_eq!(ident(id_3), "Foo2");
+        assert_eq!(ident(id_4), "Foo3");
+        assert_eq!(ident(id_5), "Foo3");
+        assert_eq!(ident(id_6), "Foo3");
+    }
+}