From 35df1c73575ce56fd11c95a2cb78f030feae30ab Mon Sep 17 00:00:00 2001
From: Techassi <git@techassi.dev>
Date: Mon, 28 Sep 2026 17:15:37 +0200
Subject: [PATCH 1/2] feat(versioned): Emit generics in plain From impl

---
 .../src/codegen/container/struct/mod.rs                | 10 ++++++++--
 1 file changed, 8 insertions(+), 2 deletions(-)

diff --git a/crates/stackable-versioned-macros/src/codegen/container/struct/mod.rs b/crates/stackable-versioned-macros/src/codegen/container/struct/mod.rs
index 8b4896a5a..61f435e73 100644
--- a/crates/stackable-versioned-macros/src/codegen/container/struct/mod.rs
+++ b/crates/stackable-versioned-macros/src/codegen/container/struct/mod.rs
@@ -478,6 +478,8 @@ impl Struct {
     ) -> TokenStream {
         // TODO (@Techassi): A bunch this stuff is duplicated in self.generate_tracking_from_impl.
         // Ideally we remove that duplication.
+        let (impl_generics, type_generics, where_clause) = self.generics.split_for_impl();
+
         let from_struct_ident = &self.common.idents.parameter;
         let struct_ident = &self.common.idents.original;
 
@@ -521,8 +523,12 @@ impl Struct {
         quote! {
             #automatically_derived
             #allow_attribute
-            impl ::core::convert::From<#from_module_ident::#struct_ident> for #for_module_ident::#struct_ident {
-                fn from(#from_struct_ident: #from_module_ident::#struct_ident) -> Self {
+            impl #impl_generics
+                ::core::convert::From<#from_module_ident::#struct_ident #type_generics>
+                for #for_module_ident::#struct_ident #type_generics
+            #where_clause
+            {
+                fn from(#from_struct_ident: #from_module_ident::#struct_ident #type_generics) -> Self {
                     Self {
                         #fields
                     }

From 38dc5840c9f4aced8967813c699c4c727ee3a05a Mon Sep 17 00:00:00 2001
From: Techassi <git@techassi.dev>
Date: Tue, 29 Sep 2026 09:20:49 +0200
Subject: [PATCH 2/2] test(versioned): Add snapshot test for generics

---
 .../tests/inputs/pass/generics.rs             | 16 ++++++
 ...d_macros__snapshots__pass@generics.rs.snap | 57 +++++++++++++++++++
 .../tests/trybuild.rs                         |  1 +
 3 files changed, 74 insertions(+)
 create mode 100644 crates/stackable-versioned-macros/tests/inputs/pass/generics.rs
 create mode 100644 crates/stackable-versioned-macros/tests/snapshots/stackable_versioned_macros__snapshots__pass@generics.rs.snap

diff --git a/crates/stackable-versioned-macros/tests/inputs/pass/generics.rs b/crates/stackable-versioned-macros/tests/inputs/pass/generics.rs
new file mode 100644
index 000000000..97619f14a
--- /dev/null
+++ b/crates/stackable-versioned-macros/tests/inputs/pass/generics.rs
@@ -0,0 +1,16 @@
+use stackable_versioned::versioned;
+// ---
+#[versioned(version(name = "v1alpha1"), version(name = "v1alpha2"))]
+// ---
+pub(crate) mod versioned {
+    struct FooSpec<Bar, Baz>
+    where
+        Bar: Default,
+        Baz: Clone,
+    {
+        bar: Bar,
+        baz: Baz,
+    }
+}
+// ---
+fn main() {}
diff --git a/crates/stackable-versioned-macros/tests/snapshots/stackable_versioned_macros__snapshots__pass@generics.rs.snap b/crates/stackable-versioned-macros/tests/snapshots/stackable_versioned_macros__snapshots__pass@generics.rs.snap
new file mode 100644
index 000000000..c587a5e7f
--- /dev/null
+++ b/crates/stackable-versioned-macros/tests/snapshots/stackable_versioned_macros__snapshots__pass@generics.rs.snap
@@ -0,0 +1,57 @@
+---
+source: crates/stackable-versioned-macros/src/lib.rs
+expression: formatted
+input_file: crates/stackable-versioned-macros/tests/inputs/pass/generics.rs
+---
+#[automatically_derived]
+pub(crate) mod v1alpha1 {
+    use super::*;
+    pub struct FooSpec<Bar, Baz>
+    where
+        Bar: Default,
+        Baz: Clone,
+    {
+        pub bar: Bar,
+        pub baz: Baz,
+    }
+}
+#[automatically_derived]
+impl<Bar, Baz> ::core::convert::From<v1alpha1::FooSpec<Bar, Baz>>
+for v1alpha2::FooSpec<Bar, Baz>
+where
+    Bar: Default,
+    Baz: Clone,
+{
+    fn from(__sv_foospec: v1alpha1::FooSpec<Bar, Baz>) -> Self {
+        Self {
+            bar: __sv_foospec.bar.into(),
+            baz: __sv_foospec.baz.into(),
+        }
+    }
+}
+#[automatically_derived]
+impl<Bar, Baz> ::core::convert::From<v1alpha2::FooSpec<Bar, Baz>>
+for v1alpha1::FooSpec<Bar, Baz>
+where
+    Bar: Default,
+    Baz: Clone,
+{
+    fn from(__sv_foospec: v1alpha2::FooSpec<Bar, Baz>) -> Self {
+        Self {
+            bar: __sv_foospec.bar.into(),
+            baz: __sv_foospec.baz.into(),
+        }
+    }
+}
+#[automatically_derived]
+pub(crate) mod v1alpha2 {
+    use super::*;
+    pub struct FooSpec<Bar, Baz>
+    where
+        Bar: Default,
+        Baz: Clone,
+    {
+        pub bar: Bar,
+        pub baz: Baz,
+    }
+}
diff --git a/crates/stackable-versioned-macros/tests/trybuild.rs b/crates/stackable-versioned-macros/tests/trybuild.rs
index 90ec9b20a..c252bb572 100644
--- a/crates/stackable-versioned-macros/tests/trybuild.rs
+++ b/crates/stackable-versioned-macros/tests/trybuild.rs
@@ -28,6 +28,7 @@ mod inputs {
         // mod docs;
         // mod downgrade_with;
         // mod enum_fields;
+        // mod generics;
         // mod module;
         // mod module_preserve;
         // mod renamed_field;