From c24b82f366868c3b3680055bc7dd58c4211ec65b Mon Sep 17 00:00:00 2001
From: "remy.baranx@gmail.com" <remy.baranx@gmail.com>
Date: Sun, 14 Apr 2024 15:25:17 +0800
Subject: [PATCH] update dojo-lang tests

---
 crates/dojo-lang/src/plugin_test_data/model  | 1098 +++++++++++-------
 crates/dojo-lang/src/plugin_test_data/system |  104 +-
 crates/dojo-lang/src/semantics/test_data/get |   56 +-
 crates/dojo-lang/src/semantics/test_data/set |   22 +-
 4 files changed, 737 insertions(+), 543 deletions(-)

diff --git a/crates/dojo-lang/src/plugin_test_data/model b/crates/dojo-lang/src/plugin_test_data/model
index 1f89d0769b..c34371cd5c 100644
--- a/crates/dojo-lang/src/plugin_test_data/model
+++ b/crates/dojo-lang/src/plugin_test_data/model
@@ -294,7 +294,7 @@ struct Player {
 type OtherPlayer = Player;
 
 impl BadModelMultipleVersionsModel of dojo::model::Model<BadModelMultipleVersions> {
-    fn entity(world: dojo::world::IWorldDispatcher, keys: Span<felt252>, layout: Span<u8>) -> BadModelMultipleVersions {
+    fn entity(world: dojo::world::IWorldDispatcher, keys: Span<felt252>, layout: dojo::model::ModelLayout) -> BadModelMultipleVersions {
         let values = dojo::world::IWorldDispatcherTrait::entity(world, selector!("BadModelMultipleVersions"), keys, layout);
 
         // TODO: Generate method to deserialize from keys / values directly to avoid
@@ -316,20 +316,25 @@ impl BadModelMultipleVersionsModel of dojo::model::Model<BadModelMultipleVersion
     }
 
     #[inline(always)]
-    fn name(self: @BadModelMultipleVersions) -> ByteArray {
+    fn name() -> ByteArray {
         "BadModelMultipleVersions"
     }
 
     #[inline(always)]
-    fn version(self: @BadModelMultipleVersions) -> u8 {
+    fn version() -> u8 {
         0
     }
 
     #[inline(always)]
-    fn selector(self: @BadModelMultipleVersions) -> felt252 {
+    fn selector() -> felt252 {
         "BadModelMultipleVersions"
     }
 
+    #[inline(always)]
+    fn instance_selector(self: @BadModelMultipleVersions) -> felt252 {
+        dojo::model::Model::<BadModelMultipleVersions>::selector()
+    }
+
     #[inline(always)]
     fn keys(self: @BadModelMultipleVersions) -> Span<felt252> {
         let mut serialized = core::array::ArrayTrait::new();
@@ -345,16 +350,29 @@ impl BadModelMultipleVersionsModel of dojo::model::Model<BadModelMultipleVersion
     }
 
     #[inline(always)]
-    fn layout(self: @BadModelMultipleVersions) -> Span<u8> {
+    fn layout() -> dojo::model::ModelLayout {
         let mut layout = core::array::ArrayTrait::new();
         dojo::database::introspect::Introspect::<BadModelMultipleVersions>::layout(ref layout);
-        core::array::ArrayTrait::span(@layout)
+        dojo::model::ModelLayout::Serial(core::array::ArrayTrait::span(@layout))
+    }
+
+    #[inline(always)]
+    fn instance_layout(self: @BadModelMultipleVersions) -> dojo::model::ModelLayout {
+        dojo::model::Model::<BadModelMultipleVersions>::layout()
     }
 
     #[inline(always)]
-    fn packed_size(self: @BadModelMultipleVersions) -> usize {
-        let mut layout = self.layout();
-        dojo::packing::calculate_packed_size(ref layout)
+    fn packed_size() -> usize {
+        match dojo::model::Model::<BadModelMultipleVersions>::layout() {
+            dojo::model::ModelLayout::Serial(layout) => {
+                let mut layout = layout.clone();
+                dojo::packing::calculate_packed_size(ref layout)
+            },
+            _ => {
+                panic!("Unexpected error");
+                0
+            }
+        }
     }
 }
 
@@ -374,15 +392,15 @@ mod bad_model_multiple_versions {
     #[abi(embed_v0)]
     impl DojoModelImpl of dojo::model::IModel<ContractState>{
         fn selector(self: @ContractState) -> felt252 {
-            "BadModelMultipleVersions"
+           dojo::model::Model::<BadModelMultipleVersions>::selector()
         }
 
         fn name(self: @ContractState) -> ByteArray {
-            "BadModelMultipleVersions"
+           dojo::model::Model::<BadModelMultipleVersions>::name()
         }
 
         fn version(self: @ContractState) -> u8 {
-            0
+           dojo::model::Model::<BadModelMultipleVersions>::version()
         }
 
         fn unpacked_size(self: @ContractState) -> usize {
@@ -390,16 +408,11 @@ mod bad_model_multiple_versions {
         }
 
         fn packed_size(self: @ContractState) -> usize {
-            let mut layout = core::array::ArrayTrait::new();
-            dojo::database::introspect::Introspect::<BadModelMultipleVersions>::layout(ref layout);
-            let mut layout_span = layout.span();
-            dojo::packing::calculate_packed_size(ref layout_span)
+            dojo::model::Model::<BadModelMultipleVersions>::packed_size()
         }
 
-        fn layout(self: @ContractState) -> Span<u8> {
-            let mut layout = core::array::ArrayTrait::new();
-            dojo::database::introspect::Introspect::<BadModelMultipleVersions>::layout(ref layout);
-            core::array::ArrayTrait::span(@layout)
+        fn layout(self: @ContractState) -> dojo::model::ModelLayout {
+            dojo::model::Model::<BadModelMultipleVersions>::layout()
         }
 
         fn schema(self: @ContractState) -> dojo::database::introspect::Ty {
@@ -415,7 +428,7 @@ mod bad_model_multiple_versions {
 }
 
 impl BadModelBadVersionTypeModel of dojo::model::Model<BadModelBadVersionType> {
-    fn entity(world: dojo::world::IWorldDispatcher, keys: Span<felt252>, layout: Span<u8>) -> BadModelBadVersionType {
+    fn entity(world: dojo::world::IWorldDispatcher, keys: Span<felt252>, layout: dojo::model::ModelLayout) -> BadModelBadVersionType {
         let values = dojo::world::IWorldDispatcherTrait::entity(world, selector!("BadModelBadVersionType"), keys, layout);
 
         // TODO: Generate method to deserialize from keys / values directly to avoid
@@ -437,20 +450,25 @@ impl BadModelBadVersionTypeModel of dojo::model::Model<BadModelBadVersionType> {
     }
 
     #[inline(always)]
-    fn name(self: @BadModelBadVersionType) -> ByteArray {
+    fn name() -> ByteArray {
         "BadModelBadVersionType"
     }
 
     #[inline(always)]
-    fn version(self: @BadModelBadVersionType) -> u8 {
+    fn version() -> u8 {
         1
     }
 
     #[inline(always)]
-    fn selector(self: @BadModelBadVersionType) -> felt252 {
+    fn selector() -> felt252 {
         selector!("BadModelBadVersionType")
     }
 
+    #[inline(always)]
+    fn instance_selector(self: @BadModelBadVersionType) -> felt252 {
+        dojo::model::Model::<BadModelBadVersionType>::selector()
+    }
+
     #[inline(always)]
     fn keys(self: @BadModelBadVersionType) -> Span<felt252> {
         let mut serialized = core::array::ArrayTrait::new();
@@ -466,16 +484,29 @@ impl BadModelBadVersionTypeModel of dojo::model::Model<BadModelBadVersionType> {
     }
 
     #[inline(always)]
-    fn layout(self: @BadModelBadVersionType) -> Span<u8> {
+    fn layout() -> dojo::model::ModelLayout {
         let mut layout = core::array::ArrayTrait::new();
         dojo::database::introspect::Introspect::<BadModelBadVersionType>::layout(ref layout);
-        core::array::ArrayTrait::span(@layout)
+        dojo::model::ModelLayout::Serial(core::array::ArrayTrait::span(@layout))
+    }
+
+    #[inline(always)]
+    fn instance_layout(self: @BadModelBadVersionType) -> dojo::model::ModelLayout {
+        dojo::model::Model::<BadModelBadVersionType>::layout()
     }
 
     #[inline(always)]
-    fn packed_size(self: @BadModelBadVersionType) -> usize {
-        let mut layout = self.layout();
-        dojo::packing::calculate_packed_size(ref layout)
+    fn packed_size() -> usize {
+        match dojo::model::Model::<BadModelBadVersionType>::layout() {
+            dojo::model::ModelLayout::Serial(layout) => {
+                let mut layout = layout.clone();
+                dojo::packing::calculate_packed_size(ref layout)
+            },
+            _ => {
+                panic!("Unexpected error");
+                0
+            }
+        }
     }
 }
 
@@ -495,15 +526,15 @@ mod bad_model_bad_version_type {
     #[abi(embed_v0)]
     impl DojoModelImpl of dojo::model::IModel<ContractState>{
         fn selector(self: @ContractState) -> felt252 {
-            selector!("BadModelBadVersionType")
+           dojo::model::Model::<BadModelBadVersionType>::selector()
         }
 
         fn name(self: @ContractState) -> ByteArray {
-            "BadModelBadVersionType"
+           dojo::model::Model::<BadModelBadVersionType>::name()
         }
 
         fn version(self: @ContractState) -> u8 {
-            1
+           dojo::model::Model::<BadModelBadVersionType>::version()
         }
 
         fn unpacked_size(self: @ContractState) -> usize {
@@ -511,16 +542,11 @@ mod bad_model_bad_version_type {
         }
 
         fn packed_size(self: @ContractState) -> usize {
-            let mut layout = core::array::ArrayTrait::new();
-            dojo::database::introspect::Introspect::<BadModelBadVersionType>::layout(ref layout);
-            let mut layout_span = layout.span();
-            dojo::packing::calculate_packed_size(ref layout_span)
+            dojo::model::Model::<BadModelBadVersionType>::packed_size()
         }
 
-        fn layout(self: @ContractState) -> Span<u8> {
-            let mut layout = core::array::ArrayTrait::new();
-            dojo::database::introspect::Introspect::<BadModelBadVersionType>::layout(ref layout);
-            core::array::ArrayTrait::span(@layout)
+        fn layout(self: @ContractState) -> dojo::model::ModelLayout {
+            dojo::model::Model::<BadModelBadVersionType>::layout()
         }
 
         fn schema(self: @ContractState) -> dojo::database::introspect::Ty {
@@ -536,7 +562,7 @@ mod bad_model_bad_version_type {
 }
 
 impl BadModelNoVersionValueModel of dojo::model::Model<BadModelNoVersionValue> {
-    fn entity(world: dojo::world::IWorldDispatcher, keys: Span<felt252>, layout: Span<u8>) -> BadModelNoVersionValue {
+    fn entity(world: dojo::world::IWorldDispatcher, keys: Span<felt252>, layout: dojo::model::ModelLayout) -> BadModelNoVersionValue {
         let values = dojo::world::IWorldDispatcherTrait::entity(world, selector!("BadModelNoVersionValue"), keys, layout);
 
         // TODO: Generate method to deserialize from keys / values directly to avoid
@@ -558,20 +584,25 @@ impl BadModelNoVersionValueModel of dojo::model::Model<BadModelNoVersionValue> {
     }
 
     #[inline(always)]
-    fn name(self: @BadModelNoVersionValue) -> ByteArray {
+    fn name() -> ByteArray {
         "BadModelNoVersionValue"
     }
 
     #[inline(always)]
-    fn version(self: @BadModelNoVersionValue) -> u8 {
+    fn version() -> u8 {
         1
     }
 
     #[inline(always)]
-    fn selector(self: @BadModelNoVersionValue) -> felt252 {
+    fn selector() -> felt252 {
         selector!("BadModelNoVersionValue")
     }
 
+    #[inline(always)]
+    fn instance_selector(self: @BadModelNoVersionValue) -> felt252 {
+        dojo::model::Model::<BadModelNoVersionValue>::selector()
+    }
+
     #[inline(always)]
     fn keys(self: @BadModelNoVersionValue) -> Span<felt252> {
         let mut serialized = core::array::ArrayTrait::new();
@@ -587,16 +618,29 @@ impl BadModelNoVersionValueModel of dojo::model::Model<BadModelNoVersionValue> {
     }
 
     #[inline(always)]
-    fn layout(self: @BadModelNoVersionValue) -> Span<u8> {
+    fn layout() -> dojo::model::ModelLayout {
         let mut layout = core::array::ArrayTrait::new();
         dojo::database::introspect::Introspect::<BadModelNoVersionValue>::layout(ref layout);
-        core::array::ArrayTrait::span(@layout)
+        dojo::model::ModelLayout::Serial(core::array::ArrayTrait::span(@layout))
+    }
+
+    #[inline(always)]
+    fn instance_layout(self: @BadModelNoVersionValue) -> dojo::model::ModelLayout {
+        dojo::model::Model::<BadModelNoVersionValue>::layout()
     }
 
     #[inline(always)]
-    fn packed_size(self: @BadModelNoVersionValue) -> usize {
-        let mut layout = self.layout();
-        dojo::packing::calculate_packed_size(ref layout)
+    fn packed_size() -> usize {
+        match dojo::model::Model::<BadModelNoVersionValue>::layout() {
+            dojo::model::ModelLayout::Serial(layout) => {
+                let mut layout = layout.clone();
+                dojo::packing::calculate_packed_size(ref layout)
+            },
+            _ => {
+                panic!("Unexpected error");
+                0
+            }
+        }
     }
 }
 
@@ -616,15 +660,15 @@ mod bad_model_no_version_value {
     #[abi(embed_v0)]
     impl DojoModelImpl of dojo::model::IModel<ContractState>{
         fn selector(self: @ContractState) -> felt252 {
-            selector!("BadModelNoVersionValue")
+           dojo::model::Model::<BadModelNoVersionValue>::selector()
         }
 
         fn name(self: @ContractState) -> ByteArray {
-            "BadModelNoVersionValue"
+           dojo::model::Model::<BadModelNoVersionValue>::name()
         }
 
         fn version(self: @ContractState) -> u8 {
-            1
+           dojo::model::Model::<BadModelNoVersionValue>::version()
         }
 
         fn unpacked_size(self: @ContractState) -> usize {
@@ -632,16 +676,11 @@ mod bad_model_no_version_value {
         }
 
         fn packed_size(self: @ContractState) -> usize {
-            let mut layout = core::array::ArrayTrait::new();
-            dojo::database::introspect::Introspect::<BadModelNoVersionValue>::layout(ref layout);
-            let mut layout_span = layout.span();
-            dojo::packing::calculate_packed_size(ref layout_span)
+            dojo::model::Model::<BadModelNoVersionValue>::packed_size()
         }
 
-        fn layout(self: @ContractState) -> Span<u8> {
-            let mut layout = core::array::ArrayTrait::new();
-            dojo::database::introspect::Introspect::<BadModelNoVersionValue>::layout(ref layout);
-            core::array::ArrayTrait::span(@layout)
+        fn layout(self: @ContractState) -> dojo::model::ModelLayout {
+            dojo::model::Model::<BadModelNoVersionValue>::layout()
         }
 
         fn schema(self: @ContractState) -> dojo::database::introspect::Ty {
@@ -657,7 +696,7 @@ mod bad_model_no_version_value {
 }
 
 impl BadModelUnexpectedArgWithValueModel of dojo::model::Model<BadModelUnexpectedArgWithValue> {
-    fn entity(world: dojo::world::IWorldDispatcher, keys: Span<felt252>, layout: Span<u8>) -> BadModelUnexpectedArgWithValue {
+    fn entity(world: dojo::world::IWorldDispatcher, keys: Span<felt252>, layout: dojo::model::ModelLayout) -> BadModelUnexpectedArgWithValue {
         let values = dojo::world::IWorldDispatcherTrait::entity(world, selector!("BadModelUnexpectedArgWithValue"), keys, layout);
 
         // TODO: Generate method to deserialize from keys / values directly to avoid
@@ -679,20 +718,25 @@ impl BadModelUnexpectedArgWithValueModel of dojo::model::Model<BadModelUnexpecte
     }
 
     #[inline(always)]
-    fn name(self: @BadModelUnexpectedArgWithValue) -> ByteArray {
+    fn name() -> ByteArray {
         "BadModelUnexpectedArgWithValue"
     }
 
     #[inline(always)]
-    fn version(self: @BadModelUnexpectedArgWithValue) -> u8 {
+    fn version() -> u8 {
         1
     }
 
     #[inline(always)]
-    fn selector(self: @BadModelUnexpectedArgWithValue) -> felt252 {
+    fn selector() -> felt252 {
         selector!("BadModelUnexpectedArgWithValue")
     }
 
+    #[inline(always)]
+    fn instance_selector(self: @BadModelUnexpectedArgWithValue) -> felt252 {
+        dojo::model::Model::<BadModelUnexpectedArgWithValue>::selector()
+    }
+
     #[inline(always)]
     fn keys(self: @BadModelUnexpectedArgWithValue) -> Span<felt252> {
         let mut serialized = core::array::ArrayTrait::new();
@@ -708,16 +752,29 @@ impl BadModelUnexpectedArgWithValueModel of dojo::model::Model<BadModelUnexpecte
     }
 
     #[inline(always)]
-    fn layout(self: @BadModelUnexpectedArgWithValue) -> Span<u8> {
+    fn layout() -> dojo::model::ModelLayout {
         let mut layout = core::array::ArrayTrait::new();
         dojo::database::introspect::Introspect::<BadModelUnexpectedArgWithValue>::layout(ref layout);
-        core::array::ArrayTrait::span(@layout)
+        dojo::model::ModelLayout::Serial(core::array::ArrayTrait::span(@layout))
     }
 
     #[inline(always)]
-    fn packed_size(self: @BadModelUnexpectedArgWithValue) -> usize {
-        let mut layout = self.layout();
-        dojo::packing::calculate_packed_size(ref layout)
+    fn instance_layout(self: @BadModelUnexpectedArgWithValue) -> dojo::model::ModelLayout {
+        dojo::model::Model::<BadModelUnexpectedArgWithValue>::layout()
+    }
+
+    #[inline(always)]
+    fn packed_size() -> usize {
+        match dojo::model::Model::<BadModelUnexpectedArgWithValue>::layout() {
+            dojo::model::ModelLayout::Serial(layout) => {
+                let mut layout = layout.clone();
+                dojo::packing::calculate_packed_size(ref layout)
+            },
+            _ => {
+                panic!("Unexpected error");
+                0
+            }
+        }
     }
 }
 
@@ -737,15 +794,15 @@ mod bad_model_unexpected_arg_with_value {
     #[abi(embed_v0)]
     impl DojoModelImpl of dojo::model::IModel<ContractState>{
         fn selector(self: @ContractState) -> felt252 {
-            selector!("BadModelUnexpectedArgWithValue")
+           dojo::model::Model::<BadModelUnexpectedArgWithValue>::selector()
         }
 
         fn name(self: @ContractState) -> ByteArray {
-            "BadModelUnexpectedArgWithValue"
+           dojo::model::Model::<BadModelUnexpectedArgWithValue>::name()
         }
 
         fn version(self: @ContractState) -> u8 {
-            1
+           dojo::model::Model::<BadModelUnexpectedArgWithValue>::version()
         }
 
         fn unpacked_size(self: @ContractState) -> usize {
@@ -753,16 +810,11 @@ mod bad_model_unexpected_arg_with_value {
         }
 
         fn packed_size(self: @ContractState) -> usize {
-            let mut layout = core::array::ArrayTrait::new();
-            dojo::database::introspect::Introspect::<BadModelUnexpectedArgWithValue>::layout(ref layout);
-            let mut layout_span = layout.span();
-            dojo::packing::calculate_packed_size(ref layout_span)
+            dojo::model::Model::<BadModelUnexpectedArgWithValue>::packed_size()
         }
 
-        fn layout(self: @ContractState) -> Span<u8> {
-            let mut layout = core::array::ArrayTrait::new();
-            dojo::database::introspect::Introspect::<BadModelUnexpectedArgWithValue>::layout(ref layout);
-            core::array::ArrayTrait::span(@layout)
+        fn layout(self: @ContractState) -> dojo::model::ModelLayout {
+            dojo::model::Model::<BadModelUnexpectedArgWithValue>::layout()
         }
 
         fn schema(self: @ContractState) -> dojo::database::introspect::Ty {
@@ -778,7 +830,7 @@ mod bad_model_unexpected_arg_with_value {
 }
 
 impl BadModelUnexpectedArgModel of dojo::model::Model<BadModelUnexpectedArg> {
-    fn entity(world: dojo::world::IWorldDispatcher, keys: Span<felt252>, layout: Span<u8>) -> BadModelUnexpectedArg {
+    fn entity(world: dojo::world::IWorldDispatcher, keys: Span<felt252>, layout: dojo::model::ModelLayout) -> BadModelUnexpectedArg {
         let values = dojo::world::IWorldDispatcherTrait::entity(world, selector!("BadModelUnexpectedArg"), keys, layout);
 
         // TODO: Generate method to deserialize from keys / values directly to avoid
@@ -800,20 +852,25 @@ impl BadModelUnexpectedArgModel of dojo::model::Model<BadModelUnexpectedArg> {
     }
 
     #[inline(always)]
-    fn name(self: @BadModelUnexpectedArg) -> ByteArray {
+    fn name() -> ByteArray {
         "BadModelUnexpectedArg"
     }
 
     #[inline(always)]
-    fn version(self: @BadModelUnexpectedArg) -> u8 {
+    fn version() -> u8 {
         1
     }
 
     #[inline(always)]
-    fn selector(self: @BadModelUnexpectedArg) -> felt252 {
+    fn selector() -> felt252 {
         selector!("BadModelUnexpectedArg")
     }
 
+    #[inline(always)]
+    fn instance_selector(self: @BadModelUnexpectedArg) -> felt252 {
+        dojo::model::Model::<BadModelUnexpectedArg>::selector()
+    }
+
     #[inline(always)]
     fn keys(self: @BadModelUnexpectedArg) -> Span<felt252> {
         let mut serialized = core::array::ArrayTrait::new();
@@ -829,16 +886,29 @@ impl BadModelUnexpectedArgModel of dojo::model::Model<BadModelUnexpectedArg> {
     }
 
     #[inline(always)]
-    fn layout(self: @BadModelUnexpectedArg) -> Span<u8> {
+    fn layout() -> dojo::model::ModelLayout {
         let mut layout = core::array::ArrayTrait::new();
         dojo::database::introspect::Introspect::<BadModelUnexpectedArg>::layout(ref layout);
-        core::array::ArrayTrait::span(@layout)
+        dojo::model::ModelLayout::Serial(core::array::ArrayTrait::span(@layout))
     }
 
     #[inline(always)]
-    fn packed_size(self: @BadModelUnexpectedArg) -> usize {
-        let mut layout = self.layout();
-        dojo::packing::calculate_packed_size(ref layout)
+    fn instance_layout(self: @BadModelUnexpectedArg) -> dojo::model::ModelLayout {
+        dojo::model::Model::<BadModelUnexpectedArg>::layout()
+    }
+
+    #[inline(always)]
+    fn packed_size() -> usize {
+        match dojo::model::Model::<BadModelUnexpectedArg>::layout() {
+            dojo::model::ModelLayout::Serial(layout) => {
+                let mut layout = layout.clone();
+                dojo::packing::calculate_packed_size(ref layout)
+            },
+            _ => {
+                panic!("Unexpected error");
+                0
+            }
+        }
     }
 }
 
@@ -858,15 +928,15 @@ mod bad_model_unexpected_arg {
     #[abi(embed_v0)]
     impl DojoModelImpl of dojo::model::IModel<ContractState>{
         fn selector(self: @ContractState) -> felt252 {
-            selector!("BadModelUnexpectedArg")
+           dojo::model::Model::<BadModelUnexpectedArg>::selector()
         }
 
         fn name(self: @ContractState) -> ByteArray {
-            "BadModelUnexpectedArg"
+           dojo::model::Model::<BadModelUnexpectedArg>::name()
         }
 
         fn version(self: @ContractState) -> u8 {
-            1
+           dojo::model::Model::<BadModelUnexpectedArg>::version()
         }
 
         fn unpacked_size(self: @ContractState) -> usize {
@@ -874,16 +944,11 @@ mod bad_model_unexpected_arg {
         }
 
         fn packed_size(self: @ContractState) -> usize {
-            let mut layout = core::array::ArrayTrait::new();
-            dojo::database::introspect::Introspect::<BadModelUnexpectedArg>::layout(ref layout);
-            let mut layout_span = layout.span();
-            dojo::packing::calculate_packed_size(ref layout_span)
+            dojo::model::Model::<BadModelUnexpectedArg>::packed_size()
         }
 
-        fn layout(self: @ContractState) -> Span<u8> {
-            let mut layout = core::array::ArrayTrait::new();
-            dojo::database::introspect::Introspect::<BadModelUnexpectedArg>::layout(ref layout);
-            core::array::ArrayTrait::span(@layout)
+        fn layout(self: @ContractState) -> dojo::model::ModelLayout {
+            dojo::model::Model::<BadModelUnexpectedArg>::layout()
         }
 
         fn schema(self: @ContractState) -> dojo::database::introspect::Ty {
@@ -899,7 +964,7 @@ mod bad_model_unexpected_arg {
 }
 
 impl BadModelNotSupportedVersionModel of dojo::model::Model<BadModelNotSupportedVersion> {
-    fn entity(world: dojo::world::IWorldDispatcher, keys: Span<felt252>, layout: Span<u8>) -> BadModelNotSupportedVersion {
+    fn entity(world: dojo::world::IWorldDispatcher, keys: Span<felt252>, layout: dojo::model::ModelLayout) -> BadModelNotSupportedVersion {
         let values = dojo::world::IWorldDispatcherTrait::entity(world, selector!("BadModelNotSupportedVersion"), keys, layout);
 
         // TODO: Generate method to deserialize from keys / values directly to avoid
@@ -921,20 +986,25 @@ impl BadModelNotSupportedVersionModel of dojo::model::Model<BadModelNotSupported
     }
 
     #[inline(always)]
-    fn name(self: @BadModelNotSupportedVersion) -> ByteArray {
+    fn name() -> ByteArray {
         "BadModelNotSupportedVersion"
     }
 
     #[inline(always)]
-    fn version(self: @BadModelNotSupportedVersion) -> u8 {
+    fn version() -> u8 {
         1
     }
 
     #[inline(always)]
-    fn selector(self: @BadModelNotSupportedVersion) -> felt252 {
+    fn selector() -> felt252 {
         selector!("BadModelNotSupportedVersion")
     }
 
+    #[inline(always)]
+    fn instance_selector(self: @BadModelNotSupportedVersion) -> felt252 {
+        dojo::model::Model::<BadModelNotSupportedVersion>::selector()
+    }
+
     #[inline(always)]
     fn keys(self: @BadModelNotSupportedVersion) -> Span<felt252> {
         let mut serialized = core::array::ArrayTrait::new();
@@ -950,16 +1020,29 @@ impl BadModelNotSupportedVersionModel of dojo::model::Model<BadModelNotSupported
     }
 
     #[inline(always)]
-    fn layout(self: @BadModelNotSupportedVersion) -> Span<u8> {
+    fn layout() -> dojo::model::ModelLayout {
         let mut layout = core::array::ArrayTrait::new();
         dojo::database::introspect::Introspect::<BadModelNotSupportedVersion>::layout(ref layout);
-        core::array::ArrayTrait::span(@layout)
+        dojo::model::ModelLayout::Serial(core::array::ArrayTrait::span(@layout))
+    }
+
+    #[inline(always)]
+    fn instance_layout(self: @BadModelNotSupportedVersion) -> dojo::model::ModelLayout {
+        dojo::model::Model::<BadModelNotSupportedVersion>::layout()
     }
 
     #[inline(always)]
-    fn packed_size(self: @BadModelNotSupportedVersion) -> usize {
-        let mut layout = self.layout();
-        dojo::packing::calculate_packed_size(ref layout)
+    fn packed_size() -> usize {
+        match dojo::model::Model::<BadModelNotSupportedVersion>::layout() {
+            dojo::model::ModelLayout::Serial(layout) => {
+                let mut layout = layout.clone();
+                dojo::packing::calculate_packed_size(ref layout)
+            },
+            _ => {
+                panic!("Unexpected error");
+                0
+            }
+        }
     }
 }
 
@@ -979,15 +1062,15 @@ mod bad_model_not_supported_version {
     #[abi(embed_v0)]
     impl DojoModelImpl of dojo::model::IModel<ContractState>{
         fn selector(self: @ContractState) -> felt252 {
-            selector!("BadModelNotSupportedVersion")
+           dojo::model::Model::<BadModelNotSupportedVersion>::selector()
         }
 
         fn name(self: @ContractState) -> ByteArray {
-            "BadModelNotSupportedVersion"
+           dojo::model::Model::<BadModelNotSupportedVersion>::name()
         }
 
         fn version(self: @ContractState) -> u8 {
-            1
+           dojo::model::Model::<BadModelNotSupportedVersion>::version()
         }
 
         fn unpacked_size(self: @ContractState) -> usize {
@@ -995,16 +1078,11 @@ mod bad_model_not_supported_version {
         }
 
         fn packed_size(self: @ContractState) -> usize {
-            let mut layout = core::array::ArrayTrait::new();
-            dojo::database::introspect::Introspect::<BadModelNotSupportedVersion>::layout(ref layout);
-            let mut layout_span = layout.span();
-            dojo::packing::calculate_packed_size(ref layout_span)
+            dojo::model::Model::<BadModelNotSupportedVersion>::packed_size()
         }
 
-        fn layout(self: @ContractState) -> Span<u8> {
-            let mut layout = core::array::ArrayTrait::new();
-            dojo::database::introspect::Introspect::<BadModelNotSupportedVersion>::layout(ref layout);
-            core::array::ArrayTrait::span(@layout)
+        fn layout(self: @ContractState) -> dojo::model::ModelLayout {
+            dojo::model::Model::<BadModelNotSupportedVersion>::layout()
         }
 
         fn schema(self: @ContractState) -> dojo::database::introspect::Ty {
@@ -1020,7 +1098,7 @@ mod bad_model_not_supported_version {
 }
 
 impl BadModelMultipleLayoutsModel of dojo::model::Model<BadModelMultipleLayouts> {
-    fn entity(world: dojo::world::IWorldDispatcher, keys: Span<felt252>, layout: Span<u8>) -> BadModelMultipleLayouts {
+    fn entity(world: dojo::world::IWorldDispatcher, keys: Span<felt252>, layout: dojo::model::ModelLayout) -> BadModelMultipleLayouts {
         let values = dojo::world::IWorldDispatcherTrait::entity(world, selector!("BadModelMultipleLayouts"), keys, layout);
 
         // TODO: Generate method to deserialize from keys / values directly to avoid
@@ -1042,20 +1120,25 @@ impl BadModelMultipleLayoutsModel of dojo::model::Model<BadModelMultipleLayouts>
     }
 
     #[inline(always)]
-    fn name(self: @BadModelMultipleLayouts) -> ByteArray {
+    fn name() -> ByteArray {
         "BadModelMultipleLayouts"
     }
 
     #[inline(always)]
-    fn version(self: @BadModelMultipleLayouts) -> u8 {
+    fn version() -> u8 {
         1
     }
 
     #[inline(always)]
-    fn selector(self: @BadModelMultipleLayouts) -> felt252 {
+    fn selector() -> felt252 {
         selector!("BadModelMultipleLayouts")
     }
 
+    #[inline(always)]
+    fn instance_selector(self: @BadModelMultipleLayouts) -> felt252 {
+        dojo::model::Model::<BadModelMultipleLayouts>::selector()
+    }
+
     #[inline(always)]
     fn keys(self: @BadModelMultipleLayouts) -> Span<felt252> {
         let mut serialized = core::array::ArrayTrait::new();
@@ -1071,16 +1154,29 @@ impl BadModelMultipleLayoutsModel of dojo::model::Model<BadModelMultipleLayouts>
     }
 
     #[inline(always)]
-    fn layout(self: @BadModelMultipleLayouts) -> Span<u8> {
+    fn layout() -> dojo::model::ModelLayout {
         let mut layout = core::array::ArrayTrait::new();
         dojo::database::introspect::Introspect::<BadModelMultipleLayouts>::layout(ref layout);
-        core::array::ArrayTrait::span(@layout)
+        dojo::model::ModelLayout::Serial(core::array::ArrayTrait::span(@layout))
     }
 
     #[inline(always)]
-    fn packed_size(self: @BadModelMultipleLayouts) -> usize {
-        let mut layout = self.layout();
-        dojo::packing::calculate_packed_size(ref layout)
+    fn instance_layout(self: @BadModelMultipleLayouts) -> dojo::model::ModelLayout {
+        dojo::model::Model::<BadModelMultipleLayouts>::layout()
+    }
+
+    #[inline(always)]
+    fn packed_size() -> usize {
+        match dojo::model::Model::<BadModelMultipleLayouts>::layout() {
+            dojo::model::ModelLayout::Serial(layout) => {
+                let mut layout = layout.clone();
+                dojo::packing::calculate_packed_size(ref layout)
+            },
+            _ => {
+                panic!("Unexpected error");
+                0
+            }
+        }
     }
 }
 
@@ -1100,15 +1196,15 @@ mod bad_model_multiple_layouts {
     #[abi(embed_v0)]
     impl DojoModelImpl of dojo::model::IModel<ContractState>{
         fn selector(self: @ContractState) -> felt252 {
-            selector!("BadModelMultipleLayouts")
+           dojo::model::Model::<BadModelMultipleLayouts>::selector()
         }
 
         fn name(self: @ContractState) -> ByteArray {
-            "BadModelMultipleLayouts"
+           dojo::model::Model::<BadModelMultipleLayouts>::name()
         }
 
         fn version(self: @ContractState) -> u8 {
-            1
+           dojo::model::Model::<BadModelMultipleLayouts>::version()
         }
 
         fn unpacked_size(self: @ContractState) -> usize {
@@ -1116,16 +1212,11 @@ mod bad_model_multiple_layouts {
         }
 
         fn packed_size(self: @ContractState) -> usize {
-            let mut layout = core::array::ArrayTrait::new();
-            dojo::database::introspect::Introspect::<BadModelMultipleLayouts>::layout(ref layout);
-            let mut layout_span = layout.span();
-            dojo::packing::calculate_packed_size(ref layout_span)
+            dojo::model::Model::<BadModelMultipleLayouts>::packed_size()
         }
 
-        fn layout(self: @ContractState) -> Span<u8> {
-            let mut layout = core::array::ArrayTrait::new();
-            dojo::database::introspect::Introspect::<BadModelMultipleLayouts>::layout(ref layout);
-            core::array::ArrayTrait::span(@layout)
+        fn layout(self: @ContractState) -> dojo::model::ModelLayout {
+            dojo::model::Model::<BadModelMultipleLayouts>::layout()
         }
 
         fn schema(self: @ContractState) -> dojo::database::introspect::Ty {
@@ -1141,7 +1232,7 @@ mod bad_model_multiple_layouts {
 }
 
 impl BadModelBadLayoutTypeModel of dojo::model::Model<BadModelBadLayoutType> {
-    fn entity(world: dojo::world::IWorldDispatcher, keys: Span<felt252>, layout: Span<u8>) -> BadModelBadLayoutType {
+    fn entity(world: dojo::world::IWorldDispatcher, keys: Span<felt252>, layout: dojo::model::ModelLayout) -> BadModelBadLayoutType {
         let values = dojo::world::IWorldDispatcherTrait::entity(world, selector!("BadModelBadLayoutType"), keys, layout);
 
         // TODO: Generate method to deserialize from keys / values directly to avoid
@@ -1163,20 +1254,25 @@ impl BadModelBadLayoutTypeModel of dojo::model::Model<BadModelBadLayoutType> {
     }
 
     #[inline(always)]
-    fn name(self: @BadModelBadLayoutType) -> ByteArray {
+    fn name() -> ByteArray {
         "BadModelBadLayoutType"
     }
 
     #[inline(always)]
-    fn version(self: @BadModelBadLayoutType) -> u8 {
+    fn version() -> u8 {
         1
     }
 
     #[inline(always)]
-    fn selector(self: @BadModelBadLayoutType) -> felt252 {
+    fn selector() -> felt252 {
         selector!("BadModelBadLayoutType")
     }
 
+    #[inline(always)]
+    fn instance_selector(self: @BadModelBadLayoutType) -> felt252 {
+        dojo::model::Model::<BadModelBadLayoutType>::selector()
+    }
+
     #[inline(always)]
     fn keys(self: @BadModelBadLayoutType) -> Span<felt252> {
         let mut serialized = core::array::ArrayTrait::new();
@@ -1192,16 +1288,29 @@ impl BadModelBadLayoutTypeModel of dojo::model::Model<BadModelBadLayoutType> {
     }
 
     #[inline(always)]
-    fn layout(self: @BadModelBadLayoutType) -> Span<u8> {
+    fn layout() -> dojo::model::ModelLayout {
         let mut layout = core::array::ArrayTrait::new();
         dojo::database::introspect::Introspect::<BadModelBadLayoutType>::layout(ref layout);
-        core::array::ArrayTrait::span(@layout)
+        dojo::model::ModelLayout::Serial(core::array::ArrayTrait::span(@layout))
     }
 
     #[inline(always)]
-    fn packed_size(self: @BadModelBadLayoutType) -> usize {
-        let mut layout = self.layout();
-        dojo::packing::calculate_packed_size(ref layout)
+    fn instance_layout(self: @BadModelBadLayoutType) -> dojo::model::ModelLayout {
+        dojo::model::Model::<BadModelBadLayoutType>::layout()
+    }
+
+    #[inline(always)]
+    fn packed_size() -> usize {
+        match dojo::model::Model::<BadModelBadLayoutType>::layout() {
+            dojo::model::ModelLayout::Serial(layout) => {
+                let mut layout = layout.clone();
+                dojo::packing::calculate_packed_size(ref layout)
+            },
+            _ => {
+                panic!("Unexpected error");
+                0
+            }
+        }
     }
 }
 
@@ -1221,15 +1330,15 @@ mod bad_model_bad_layout_type {
     #[abi(embed_v0)]
     impl DojoModelImpl of dojo::model::IModel<ContractState>{
         fn selector(self: @ContractState) -> felt252 {
-            selector!("BadModelBadLayoutType")
+           dojo::model::Model::<BadModelBadLayoutType>::selector()
         }
 
         fn name(self: @ContractState) -> ByteArray {
-            "BadModelBadLayoutType"
+           dojo::model::Model::<BadModelBadLayoutType>::name()
         }
 
         fn version(self: @ContractState) -> u8 {
-            1
+           dojo::model::Model::<BadModelBadLayoutType>::version()
         }
 
         fn unpacked_size(self: @ContractState) -> usize {
@@ -1237,16 +1346,11 @@ mod bad_model_bad_layout_type {
         }
 
         fn packed_size(self: @ContractState) -> usize {
-            let mut layout = core::array::ArrayTrait::new();
-            dojo::database::introspect::Introspect::<BadModelBadLayoutType>::layout(ref layout);
-            let mut layout_span = layout.span();
-            dojo::packing::calculate_packed_size(ref layout_span)
+            dojo::model::Model::<BadModelBadLayoutType>::packed_size()
         }
 
-        fn layout(self: @ContractState) -> Span<u8> {
-            let mut layout = core::array::ArrayTrait::new();
-            dojo::database::introspect::Introspect::<BadModelBadLayoutType>::layout(ref layout);
-            core::array::ArrayTrait::span(@layout)
+        fn layout(self: @ContractState) -> dojo::model::ModelLayout {
+            dojo::model::Model::<BadModelBadLayoutType>::layout()
         }
 
         fn schema(self: @ContractState) -> dojo::database::introspect::Ty {
@@ -1262,7 +1366,7 @@ mod bad_model_bad_layout_type {
 }
 
 impl BadModelNoLayoutValueModel of dojo::model::Model<BadModelNoLayoutValue> {
-    fn entity(world: dojo::world::IWorldDispatcher, keys: Span<felt252>, layout: Span<u8>) -> BadModelNoLayoutValue {
+    fn entity(world: dojo::world::IWorldDispatcher, keys: Span<felt252>, layout: dojo::model::ModelLayout) -> BadModelNoLayoutValue {
         let values = dojo::world::IWorldDispatcherTrait::entity(world, selector!("BadModelNoLayoutValue"), keys, layout);
 
         // TODO: Generate method to deserialize from keys / values directly to avoid
@@ -1284,20 +1388,25 @@ impl BadModelNoLayoutValueModel of dojo::model::Model<BadModelNoLayoutValue> {
     }
 
     #[inline(always)]
-    fn name(self: @BadModelNoLayoutValue) -> ByteArray {
+    fn name() -> ByteArray {
         "BadModelNoLayoutValue"
     }
 
     #[inline(always)]
-    fn version(self: @BadModelNoLayoutValue) -> u8 {
+    fn version() -> u8 {
         1
     }
 
     #[inline(always)]
-    fn selector(self: @BadModelNoLayoutValue) -> felt252 {
+    fn selector() -> felt252 {
         selector!("BadModelNoLayoutValue")
     }
 
+    #[inline(always)]
+    fn instance_selector(self: @BadModelNoLayoutValue) -> felt252 {
+        dojo::model::Model::<BadModelNoLayoutValue>::selector()
+    }
+
     #[inline(always)]
     fn keys(self: @BadModelNoLayoutValue) -> Span<felt252> {
         let mut serialized = core::array::ArrayTrait::new();
@@ -1313,16 +1422,29 @@ impl BadModelNoLayoutValueModel of dojo::model::Model<BadModelNoLayoutValue> {
     }
 
     #[inline(always)]
-    fn layout(self: @BadModelNoLayoutValue) -> Span<u8> {
+    fn layout() -> dojo::model::ModelLayout {
         let mut layout = core::array::ArrayTrait::new();
         dojo::database::introspect::Introspect::<BadModelNoLayoutValue>::layout(ref layout);
-        core::array::ArrayTrait::span(@layout)
+        dojo::model::ModelLayout::Serial(core::array::ArrayTrait::span(@layout))
     }
 
     #[inline(always)]
-    fn packed_size(self: @BadModelNoLayoutValue) -> usize {
-        let mut layout = self.layout();
-        dojo::packing::calculate_packed_size(ref layout)
+    fn instance_layout(self: @BadModelNoLayoutValue) -> dojo::model::ModelLayout {
+        dojo::model::Model::<BadModelNoLayoutValue>::layout()
+    }
+
+    #[inline(always)]
+    fn packed_size() -> usize {
+        match dojo::model::Model::<BadModelNoLayoutValue>::layout() {
+            dojo::model::ModelLayout::Serial(layout) => {
+                let mut layout = layout.clone();
+                dojo::packing::calculate_packed_size(ref layout)
+            },
+            _ => {
+                panic!("Unexpected error");
+                0
+            }
+        }
     }
 }
 
@@ -1342,15 +1464,15 @@ mod bad_model_no_layout_value {
     #[abi(embed_v0)]
     impl DojoModelImpl of dojo::model::IModel<ContractState>{
         fn selector(self: @ContractState) -> felt252 {
-            selector!("BadModelNoLayoutValue")
+           dojo::model::Model::<BadModelNoLayoutValue>::selector()
         }
 
         fn name(self: @ContractState) -> ByteArray {
-            "BadModelNoLayoutValue"
+           dojo::model::Model::<BadModelNoLayoutValue>::name()
         }
 
         fn version(self: @ContractState) -> u8 {
-            1
+           dojo::model::Model::<BadModelNoLayoutValue>::version()
         }
 
         fn unpacked_size(self: @ContractState) -> usize {
@@ -1358,16 +1480,11 @@ mod bad_model_no_layout_value {
         }
 
         fn packed_size(self: @ContractState) -> usize {
-            let mut layout = core::array::ArrayTrait::new();
-            dojo::database::introspect::Introspect::<BadModelNoLayoutValue>::layout(ref layout);
-            let mut layout_span = layout.span();
-            dojo::packing::calculate_packed_size(ref layout_span)
+            dojo::model::Model::<BadModelNoLayoutValue>::packed_size()
         }
 
-        fn layout(self: @ContractState) -> Span<u8> {
-            let mut layout = core::array::ArrayTrait::new();
-            dojo::database::introspect::Introspect::<BadModelNoLayoutValue>::layout(ref layout);
-            core::array::ArrayTrait::span(@layout)
+        fn layout(self: @ContractState) -> dojo::model::ModelLayout {
+            dojo::model::Model::<BadModelNoLayoutValue>::layout()
         }
 
         fn schema(self: @ContractState) -> dojo::database::introspect::Ty {
@@ -1383,7 +1500,7 @@ mod bad_model_no_layout_value {
 }
 
 impl BadModelNotSupportedLayoutModel of dojo::model::Model<BadModelNotSupportedLayout> {
-    fn entity(world: dojo::world::IWorldDispatcher, keys: Span<felt252>, layout: Span<u8>) -> BadModelNotSupportedLayout {
+    fn entity(world: dojo::world::IWorldDispatcher, keys: Span<felt252>, layout: dojo::model::ModelLayout) -> BadModelNotSupportedLayout {
         let values = dojo::world::IWorldDispatcherTrait::entity(world, selector!("BadModelNotSupportedLayout"), keys, layout);
 
         // TODO: Generate method to deserialize from keys / values directly to avoid
@@ -1405,20 +1522,25 @@ impl BadModelNotSupportedLayoutModel of dojo::model::Model<BadModelNotSupportedL
     }
 
     #[inline(always)]
-    fn name(self: @BadModelNotSupportedLayout) -> ByteArray {
+    fn name() -> ByteArray {
         "BadModelNotSupportedLayout"
     }
 
     #[inline(always)]
-    fn version(self: @BadModelNotSupportedLayout) -> u8 {
+    fn version() -> u8 {
         1
     }
 
     #[inline(always)]
-    fn selector(self: @BadModelNotSupportedLayout) -> felt252 {
+    fn selector() -> felt252 {
         selector!("BadModelNotSupportedLayout")
     }
 
+    #[inline(always)]
+    fn instance_selector(self: @BadModelNotSupportedLayout) -> felt252 {
+        dojo::model::Model::<BadModelNotSupportedLayout>::selector()
+    }
+
     #[inline(always)]
     fn keys(self: @BadModelNotSupportedLayout) -> Span<felt252> {
         let mut serialized = core::array::ArrayTrait::new();
@@ -1434,16 +1556,29 @@ impl BadModelNotSupportedLayoutModel of dojo::model::Model<BadModelNotSupportedL
     }
 
     #[inline(always)]
-    fn layout(self: @BadModelNotSupportedLayout) -> Span<u8> {
+    fn layout() -> dojo::model::ModelLayout {
         let mut layout = core::array::ArrayTrait::new();
         dojo::database::introspect::Introspect::<BadModelNotSupportedLayout>::layout(ref layout);
-        core::array::ArrayTrait::span(@layout)
+        dojo::model::ModelLayout::Serial(core::array::ArrayTrait::span(@layout))
+    }
+
+    #[inline(always)]
+    fn instance_layout(self: @BadModelNotSupportedLayout) -> dojo::model::ModelLayout {
+        dojo::model::Model::<BadModelNotSupportedLayout>::layout()
     }
 
     #[inline(always)]
-    fn packed_size(self: @BadModelNotSupportedLayout) -> usize {
-        let mut layout = self.layout();
-        dojo::packing::calculate_packed_size(ref layout)
+    fn packed_size() -> usize {
+        match dojo::model::Model::<BadModelNotSupportedLayout>::layout() {
+            dojo::model::ModelLayout::Serial(layout) => {
+                let mut layout = layout.clone();
+                dojo::packing::calculate_packed_size(ref layout)
+            },
+            _ => {
+                panic!("Unexpected error");
+                0
+            }
+        }
     }
 }
 
@@ -1463,15 +1598,15 @@ mod bad_model_not_supported_layout {
     #[abi(embed_v0)]
     impl DojoModelImpl of dojo::model::IModel<ContractState>{
         fn selector(self: @ContractState) -> felt252 {
-            selector!("BadModelNotSupportedLayout")
+           dojo::model::Model::<BadModelNotSupportedLayout>::selector()
         }
 
         fn name(self: @ContractState) -> ByteArray {
-            "BadModelNotSupportedLayout"
+           dojo::model::Model::<BadModelNotSupportedLayout>::name()
         }
 
         fn version(self: @ContractState) -> u8 {
-            1
+           dojo::model::Model::<BadModelNotSupportedLayout>::version()
         }
 
         fn unpacked_size(self: @ContractState) -> usize {
@@ -1479,16 +1614,11 @@ mod bad_model_not_supported_layout {
         }
 
         fn packed_size(self: @ContractState) -> usize {
-            let mut layout = core::array::ArrayTrait::new();
-            dojo::database::introspect::Introspect::<BadModelNotSupportedLayout>::layout(ref layout);
-            let mut layout_span = layout.span();
-            dojo::packing::calculate_packed_size(ref layout_span)
+            dojo::model::Model::<BadModelNotSupportedLayout>::packed_size()
         }
 
-        fn layout(self: @ContractState) -> Span<u8> {
-            let mut layout = core::array::ArrayTrait::new();
-            dojo::database::introspect::Introspect::<BadModelNotSupportedLayout>::layout(ref layout);
-            core::array::ArrayTrait::span(@layout)
+        fn layout(self: @ContractState) -> dojo::model::ModelLayout {
+            dojo::model::Model::<BadModelNotSupportedLayout>::layout()
         }
 
         fn schema(self: @ContractState) -> dojo::database::introspect::Ty {
@@ -1504,7 +1634,7 @@ mod bad_model_not_supported_layout {
 }
 
 impl Modelv0Model of dojo::model::Model<Modelv0> {
-    fn entity(world: dojo::world::IWorldDispatcher, keys: Span<felt252>, layout: Span<u8>) -> Modelv0 {
+    fn entity(world: dojo::world::IWorldDispatcher, keys: Span<felt252>, layout: dojo::model::ModelLayout) -> Modelv0 {
         let values = dojo::world::IWorldDispatcherTrait::entity(world, selector!("Modelv0"), keys, layout);
 
         // TODO: Generate method to deserialize from keys / values directly to avoid
@@ -1526,20 +1656,25 @@ impl Modelv0Model of dojo::model::Model<Modelv0> {
     }
 
     #[inline(always)]
-    fn name(self: @Modelv0) -> ByteArray {
+    fn name() -> ByteArray {
         "Modelv0"
     }
 
     #[inline(always)]
-    fn version(self: @Modelv0) -> u8 {
+    fn version() -> u8 {
         0
     }
 
     #[inline(always)]
-    fn selector(self: @Modelv0) -> felt252 {
+    fn selector() -> felt252 {
         "Modelv0"
     }
 
+    #[inline(always)]
+    fn instance_selector(self: @Modelv0) -> felt252 {
+        dojo::model::Model::<Modelv0>::selector()
+    }
+
     #[inline(always)]
     fn keys(self: @Modelv0) -> Span<felt252> {
         let mut serialized = core::array::ArrayTrait::new();
@@ -1555,16 +1690,29 @@ impl Modelv0Model of dojo::model::Model<Modelv0> {
     }
 
     #[inline(always)]
-    fn layout(self: @Modelv0) -> Span<u8> {
+    fn layout() -> dojo::model::ModelLayout {
         let mut layout = core::array::ArrayTrait::new();
         dojo::database::introspect::Introspect::<Modelv0>::layout(ref layout);
-        core::array::ArrayTrait::span(@layout)
+        dojo::model::ModelLayout::Serial(core::array::ArrayTrait::span(@layout))
+    }
+
+    #[inline(always)]
+    fn instance_layout(self: @Modelv0) -> dojo::model::ModelLayout {
+        dojo::model::Model::<Modelv0>::layout()
     }
 
     #[inline(always)]
-    fn packed_size(self: @Modelv0) -> usize {
-        let mut layout = self.layout();
-        dojo::packing::calculate_packed_size(ref layout)
+    fn packed_size() -> usize {
+        match dojo::model::Model::<Modelv0>::layout() {
+            dojo::model::ModelLayout::Serial(layout) => {
+                let mut layout = layout.clone();
+                dojo::packing::calculate_packed_size(ref layout)
+            },
+            _ => {
+                panic!("Unexpected error");
+                0
+            }
+        }
     }
 }
 
@@ -1584,15 +1732,15 @@ mod modelv_0 {
     #[abi(embed_v0)]
     impl DojoModelImpl of dojo::model::IModel<ContractState>{
         fn selector(self: @ContractState) -> felt252 {
-            "Modelv0"
+           dojo::model::Model::<Modelv0>::selector()
         }
 
         fn name(self: @ContractState) -> ByteArray {
-            "Modelv0"
+           dojo::model::Model::<Modelv0>::name()
         }
 
         fn version(self: @ContractState) -> u8 {
-            0
+           dojo::model::Model::<Modelv0>::version()
         }
 
         fn unpacked_size(self: @ContractState) -> usize {
@@ -1600,16 +1748,11 @@ mod modelv_0 {
         }
 
         fn packed_size(self: @ContractState) -> usize {
-            let mut layout = core::array::ArrayTrait::new();
-            dojo::database::introspect::Introspect::<Modelv0>::layout(ref layout);
-            let mut layout_span = layout.span();
-            dojo::packing::calculate_packed_size(ref layout_span)
+            dojo::model::Model::<Modelv0>::packed_size()
         }
 
-        fn layout(self: @ContractState) -> Span<u8> {
-            let mut layout = core::array::ArrayTrait::new();
-            dojo::database::introspect::Introspect::<Modelv0>::layout(ref layout);
-            core::array::ArrayTrait::span(@layout)
+        fn layout(self: @ContractState) -> dojo::model::ModelLayout {
+            dojo::model::Model::<Modelv0>::layout()
         }
 
         fn schema(self: @ContractState) -> dojo::database::introspect::Ty {
@@ -1625,7 +1768,7 @@ mod modelv_0 {
 }
 
 impl ModelSerialShortStringModel of dojo::model::Model<ModelSerialShortString> {
-    fn entity(world: dojo::world::IWorldDispatcher, keys: Span<felt252>, layout: Span<u8>) -> ModelSerialShortString {
+    fn entity(world: dojo::world::IWorldDispatcher, keys: Span<felt252>, layout: dojo::model::ModelLayout) -> ModelSerialShortString {
         let values = dojo::world::IWorldDispatcherTrait::entity(world, selector!("ModelSerialShortString"), keys, layout);
 
         // TODO: Generate method to deserialize from keys / values directly to avoid
@@ -1647,20 +1790,25 @@ impl ModelSerialShortStringModel of dojo::model::Model<ModelSerialShortString> {
     }
 
     #[inline(always)]
-    fn name(self: @ModelSerialShortString) -> ByteArray {
+    fn name() -> ByteArray {
         "ModelSerialShortString"
     }
 
     #[inline(always)]
-    fn version(self: @ModelSerialShortString) -> u8 {
+    fn version() -> u8 {
         1
     }
 
     #[inline(always)]
-    fn selector(self: @ModelSerialShortString) -> felt252 {
+    fn selector() -> felt252 {
         selector!("ModelSerialShortString")
     }
 
+    #[inline(always)]
+    fn instance_selector(self: @ModelSerialShortString) -> felt252 {
+        dojo::model::Model::<ModelSerialShortString>::selector()
+    }
+
     #[inline(always)]
     fn keys(self: @ModelSerialShortString) -> Span<felt252> {
         let mut serialized = core::array::ArrayTrait::new();
@@ -1676,16 +1824,29 @@ impl ModelSerialShortStringModel of dojo::model::Model<ModelSerialShortString> {
     }
 
     #[inline(always)]
-    fn layout(self: @ModelSerialShortString) -> Span<u8> {
+    fn layout() -> dojo::model::ModelLayout {
         let mut layout = core::array::ArrayTrait::new();
         dojo::database::introspect::Introspect::<ModelSerialShortString>::layout(ref layout);
-        core::array::ArrayTrait::span(@layout)
+        dojo::model::ModelLayout::Serial(core::array::ArrayTrait::span(@layout))
+    }
+
+    #[inline(always)]
+    fn instance_layout(self: @ModelSerialShortString) -> dojo::model::ModelLayout {
+        dojo::model::Model::<ModelSerialShortString>::layout()
     }
 
     #[inline(always)]
-    fn packed_size(self: @ModelSerialShortString) -> usize {
-        let mut layout = self.layout();
-        dojo::packing::calculate_packed_size(ref layout)
+    fn packed_size() -> usize {
+        match dojo::model::Model::<ModelSerialShortString>::layout() {
+            dojo::model::ModelLayout::Serial(layout) => {
+                let mut layout = layout.clone();
+                dojo::packing::calculate_packed_size(ref layout)
+            },
+            _ => {
+                panic!("Unexpected error");
+                0
+            }
+        }
     }
 }
 
@@ -1705,15 +1866,15 @@ mod model_serial_short_string {
     #[abi(embed_v0)]
     impl DojoModelImpl of dojo::model::IModel<ContractState>{
         fn selector(self: @ContractState) -> felt252 {
-            selector!("ModelSerialShortString")
+           dojo::model::Model::<ModelSerialShortString>::selector()
         }
 
         fn name(self: @ContractState) -> ByteArray {
-            "ModelSerialShortString"
+           dojo::model::Model::<ModelSerialShortString>::name()
         }
 
         fn version(self: @ContractState) -> u8 {
-            1
+           dojo::model::Model::<ModelSerialShortString>::version()
         }
 
         fn unpacked_size(self: @ContractState) -> usize {
@@ -1721,16 +1882,11 @@ mod model_serial_short_string {
         }
 
         fn packed_size(self: @ContractState) -> usize {
-            let mut layout = core::array::ArrayTrait::new();
-            dojo::database::introspect::Introspect::<ModelSerialShortString>::layout(ref layout);
-            let mut layout_span = layout.span();
-            dojo::packing::calculate_packed_size(ref layout_span)
+            dojo::model::Model::<ModelSerialShortString>::packed_size()
         }
 
-        fn layout(self: @ContractState) -> Span<u8> {
-            let mut layout = core::array::ArrayTrait::new();
-            dojo::database::introspect::Introspect::<ModelSerialShortString>::layout(ref layout);
-            core::array::ArrayTrait::span(@layout)
+        fn layout(self: @ContractState) -> dojo::model::ModelLayout {
+            dojo::model::Model::<ModelSerialShortString>::layout()
         }
 
         fn schema(self: @ContractState) -> dojo::database::introspect::Ty {
@@ -1746,7 +1902,7 @@ mod model_serial_short_string {
 }
 
 impl ModelSerialStringModel of dojo::model::Model<ModelSerialString> {
-    fn entity(world: dojo::world::IWorldDispatcher, keys: Span<felt252>, layout: Span<u8>) -> ModelSerialString {
+    fn entity(world: dojo::world::IWorldDispatcher, keys: Span<felt252>, layout: dojo::model::ModelLayout) -> ModelSerialString {
         let values = dojo::world::IWorldDispatcherTrait::entity(world, selector!("ModelSerialString"), keys, layout);
 
         // TODO: Generate method to deserialize from keys / values directly to avoid
@@ -1768,20 +1924,25 @@ impl ModelSerialStringModel of dojo::model::Model<ModelSerialString> {
     }
 
     #[inline(always)]
-    fn name(self: @ModelSerialString) -> ByteArray {
+    fn name() -> ByteArray {
         "ModelSerialString"
     }
 
     #[inline(always)]
-    fn version(self: @ModelSerialString) -> u8 {
+    fn version() -> u8 {
         1
     }
 
     #[inline(always)]
-    fn selector(self: @ModelSerialString) -> felt252 {
+    fn selector() -> felt252 {
         selector!("ModelSerialString")
     }
 
+    #[inline(always)]
+    fn instance_selector(self: @ModelSerialString) -> felt252 {
+        dojo::model::Model::<ModelSerialString>::selector()
+    }
+
     #[inline(always)]
     fn keys(self: @ModelSerialString) -> Span<felt252> {
         let mut serialized = core::array::ArrayTrait::new();
@@ -1797,16 +1958,29 @@ impl ModelSerialStringModel of dojo::model::Model<ModelSerialString> {
     }
 
     #[inline(always)]
-    fn layout(self: @ModelSerialString) -> Span<u8> {
+    fn layout() -> dojo::model::ModelLayout {
         let mut layout = core::array::ArrayTrait::new();
         dojo::database::introspect::Introspect::<ModelSerialString>::layout(ref layout);
-        core::array::ArrayTrait::span(@layout)
+        dojo::model::ModelLayout::Serial(core::array::ArrayTrait::span(@layout))
     }
 
     #[inline(always)]
-    fn packed_size(self: @ModelSerialString) -> usize {
-        let mut layout = self.layout();
-        dojo::packing::calculate_packed_size(ref layout)
+    fn instance_layout(self: @ModelSerialString) -> dojo::model::ModelLayout {
+        dojo::model::Model::<ModelSerialString>::layout()
+    }
+
+    #[inline(always)]
+    fn packed_size() -> usize {
+        match dojo::model::Model::<ModelSerialString>::layout() {
+            dojo::model::ModelLayout::Serial(layout) => {
+                let mut layout = layout.clone();
+                dojo::packing::calculate_packed_size(ref layout)
+            },
+            _ => {
+                panic!("Unexpected error");
+                0
+            }
+        }
     }
 }
 
@@ -1826,15 +2000,15 @@ mod model_serial_string {
     #[abi(embed_v0)]
     impl DojoModelImpl of dojo::model::IModel<ContractState>{
         fn selector(self: @ContractState) -> felt252 {
-            selector!("ModelSerialString")
+           dojo::model::Model::<ModelSerialString>::selector()
         }
 
         fn name(self: @ContractState) -> ByteArray {
-            "ModelSerialString"
+           dojo::model::Model::<ModelSerialString>::name()
         }
 
         fn version(self: @ContractState) -> u8 {
-            1
+           dojo::model::Model::<ModelSerialString>::version()
         }
 
         fn unpacked_size(self: @ContractState) -> usize {
@@ -1842,16 +2016,11 @@ mod model_serial_string {
         }
 
         fn packed_size(self: @ContractState) -> usize {
-            let mut layout = core::array::ArrayTrait::new();
-            dojo::database::introspect::Introspect::<ModelSerialString>::layout(ref layout);
-            let mut layout_span = layout.span();
-            dojo::packing::calculate_packed_size(ref layout_span)
+            dojo::model::Model::<ModelSerialString>::packed_size()
         }
 
-        fn layout(self: @ContractState) -> Span<u8> {
-            let mut layout = core::array::ArrayTrait::new();
-            dojo::database::introspect::Introspect::<ModelSerialString>::layout(ref layout);
-            core::array::ArrayTrait::span(@layout)
+        fn layout(self: @ContractState) -> dojo::model::ModelLayout {
+            dojo::model::Model::<ModelSerialString>::layout()
         }
 
         fn schema(self: @ContractState) -> dojo::database::introspect::Ty {
@@ -1867,7 +2036,7 @@ mod model_serial_string {
 }
 
 impl PositionModel of dojo::model::Model<Position> {
-    fn entity(world: dojo::world::IWorldDispatcher, keys: Span<felt252>, layout: Span<u8>) -> Position {
+    fn entity(world: dojo::world::IWorldDispatcher, keys: Span<felt252>, layout: dojo::model::ModelLayout) -> Position {
         let values = dojo::world::IWorldDispatcherTrait::entity(world, selector!("Position"), keys, layout);
 
         // TODO: Generate method to deserialize from keys / values directly to avoid
@@ -1889,20 +2058,25 @@ impl PositionModel of dojo::model::Model<Position> {
     }
 
     #[inline(always)]
-    fn name(self: @Position) -> ByteArray {
+    fn name() -> ByteArray {
         "Position"
     }
 
     #[inline(always)]
-    fn version(self: @Position) -> u8 {
+    fn version() -> u8 {
         1
     }
 
     #[inline(always)]
-    fn selector(self: @Position) -> felt252 {
+    fn selector() -> felt252 {
         selector!("Position")
     }
 
+    #[inline(always)]
+    fn instance_selector(self: @Position) -> felt252 {
+        dojo::model::Model::<Position>::selector()
+    }
+
     #[inline(always)]
     fn keys(self: @Position) -> Span<felt252> {
         let mut serialized = core::array::ArrayTrait::new();
@@ -1918,16 +2092,29 @@ impl PositionModel of dojo::model::Model<Position> {
     }
 
     #[inline(always)]
-    fn layout(self: @Position) -> Span<u8> {
+    fn layout() -> dojo::model::ModelLayout {
         let mut layout = core::array::ArrayTrait::new();
         dojo::database::introspect::Introspect::<Position>::layout(ref layout);
-        core::array::ArrayTrait::span(@layout)
+        dojo::model::ModelLayout::Serial(core::array::ArrayTrait::span(@layout))
     }
 
     #[inline(always)]
-    fn packed_size(self: @Position) -> usize {
-        let mut layout = self.layout();
-        dojo::packing::calculate_packed_size(ref layout)
+    fn instance_layout(self: @Position) -> dojo::model::ModelLayout {
+        dojo::model::Model::<Position>::layout()
+    }
+
+    #[inline(always)]
+    fn packed_size() -> usize {
+        match dojo::model::Model::<Position>::layout() {
+            dojo::model::ModelLayout::Serial(layout) => {
+                let mut layout = layout.clone();
+                dojo::packing::calculate_packed_size(ref layout)
+            },
+            _ => {
+                panic!("Unexpected error");
+                0
+            }
+        }
     }
 }
 
@@ -1947,15 +2134,15 @@ mod position {
     #[abi(embed_v0)]
     impl DojoModelImpl of dojo::model::IModel<ContractState>{
         fn selector(self: @ContractState) -> felt252 {
-            selector!("Position")
+           dojo::model::Model::<Position>::selector()
         }
 
         fn name(self: @ContractState) -> ByteArray {
-            "Position"
+           dojo::model::Model::<Position>::name()
         }
 
         fn version(self: @ContractState) -> u8 {
-            1
+           dojo::model::Model::<Position>::version()
         }
 
         fn unpacked_size(self: @ContractState) -> usize {
@@ -1963,16 +2150,11 @@ mod position {
         }
 
         fn packed_size(self: @ContractState) -> usize {
-            let mut layout = core::array::ArrayTrait::new();
-            dojo::database::introspect::Introspect::<Position>::layout(ref layout);
-            let mut layout_span = layout.span();
-            dojo::packing::calculate_packed_size(ref layout_span)
+            dojo::model::Model::<Position>::packed_size()
         }
 
-        fn layout(self: @ContractState) -> Span<u8> {
-            let mut layout = core::array::ArrayTrait::new();
-            dojo::database::introspect::Introspect::<Position>::layout(ref layout);
-            core::array::ArrayTrait::span(@layout)
+        fn layout(self: @ContractState) -> dojo::model::ModelLayout {
+            dojo::model::Model::<Position>::layout()
         }
 
         fn schema(self: @ContractState) -> dojo::database::introspect::Ty {
@@ -1988,7 +2170,7 @@ mod position {
 }
 
 impl RolesModel of dojo::model::Model<Roles> {
-    fn entity(world: dojo::world::IWorldDispatcher, keys: Span<felt252>, layout: Span<u8>) -> Roles {
+    fn entity(world: dojo::world::IWorldDispatcher, keys: Span<felt252>, layout: dojo::model::ModelLayout) -> Roles {
         let values = dojo::world::IWorldDispatcherTrait::entity(world, selector!("Roles"), keys, layout);
 
         // TODO: Generate method to deserialize from keys / values directly to avoid
@@ -2010,20 +2192,25 @@ impl RolesModel of dojo::model::Model<Roles> {
     }
 
     #[inline(always)]
-    fn name(self: @Roles) -> ByteArray {
+    fn name() -> ByteArray {
         "Roles"
     }
 
     #[inline(always)]
-    fn version(self: @Roles) -> u8 {
+    fn version() -> u8 {
         1
     }
 
     #[inline(always)]
-    fn selector(self: @Roles) -> felt252 {
+    fn selector() -> felt252 {
         selector!("Roles")
     }
 
+    #[inline(always)]
+    fn instance_selector(self: @Roles) -> felt252 {
+        dojo::model::Model::<Roles>::selector()
+    }
+
     #[inline(always)]
     fn keys(self: @Roles) -> Span<felt252> {
         let mut serialized = core::array::ArrayTrait::new();
@@ -2039,16 +2226,29 @@ impl RolesModel of dojo::model::Model<Roles> {
     }
 
     #[inline(always)]
-    fn layout(self: @Roles) -> Span<u8> {
+    fn layout() -> dojo::model::ModelLayout {
         let mut layout = core::array::ArrayTrait::new();
         dojo::database::introspect::Introspect::<Roles>::layout(ref layout);
-        core::array::ArrayTrait::span(@layout)
+        dojo::model::ModelLayout::Serial(core::array::ArrayTrait::span(@layout))
+    }
+
+    #[inline(always)]
+    fn instance_layout(self: @Roles) -> dojo::model::ModelLayout {
+        dojo::model::Model::<Roles>::layout()
     }
 
     #[inline(always)]
-    fn packed_size(self: @Roles) -> usize {
-        let mut layout = self.layout();
-        dojo::packing::calculate_packed_size(ref layout)
+    fn packed_size() -> usize {
+        match dojo::model::Model::<Roles>::layout() {
+            dojo::model::ModelLayout::Serial(layout) => {
+                let mut layout = layout.clone();
+                dojo::packing::calculate_packed_size(ref layout)
+            },
+            _ => {
+                panic!("Unexpected error");
+                0
+            }
+        }
     }
 }
 
@@ -2068,15 +2268,15 @@ mod roles {
     #[abi(embed_v0)]
     impl DojoModelImpl of dojo::model::IModel<ContractState>{
         fn selector(self: @ContractState) -> felt252 {
-            selector!("Roles")
+           dojo::model::Model::<Roles>::selector()
         }
 
         fn name(self: @ContractState) -> ByteArray {
-            "Roles"
+           dojo::model::Model::<Roles>::name()
         }
 
         fn version(self: @ContractState) -> u8 {
-            1
+           dojo::model::Model::<Roles>::version()
         }
 
         fn unpacked_size(self: @ContractState) -> usize {
@@ -2084,16 +2284,11 @@ mod roles {
         }
 
         fn packed_size(self: @ContractState) -> usize {
-            let mut layout = core::array::ArrayTrait::new();
-            dojo::database::introspect::Introspect::<Roles>::layout(ref layout);
-            let mut layout_span = layout.span();
-            dojo::packing::calculate_packed_size(ref layout_span)
+            dojo::model::Model::<Roles>::packed_size()
         }
 
-        fn layout(self: @ContractState) -> Span<u8> {
-            let mut layout = core::array::ArrayTrait::new();
-            dojo::database::introspect::Introspect::<Roles>::layout(ref layout);
-            core::array::ArrayTrait::span(@layout)
+        fn layout(self: @ContractState) -> dojo::model::ModelLayout {
+            dojo::model::Model::<Roles>::layout()
         }
 
         fn schema(self: @ContractState) -> dojo::database::introspect::Ty {
@@ -2109,7 +2304,7 @@ mod roles {
 }
 
 impl OnlyKeyModelModel of dojo::model::Model<OnlyKeyModel> {
-    fn entity(world: dojo::world::IWorldDispatcher, keys: Span<felt252>, layout: Span<u8>) -> OnlyKeyModel {
+    fn entity(world: dojo::world::IWorldDispatcher, keys: Span<felt252>, layout: dojo::model::ModelLayout) -> OnlyKeyModel {
         let values = dojo::world::IWorldDispatcherTrait::entity(world, selector!("OnlyKeyModel"), keys, layout);
 
         // TODO: Generate method to deserialize from keys / values directly to avoid
@@ -2131,20 +2326,25 @@ impl OnlyKeyModelModel of dojo::model::Model<OnlyKeyModel> {
     }
 
     #[inline(always)]
-    fn name(self: @OnlyKeyModel) -> ByteArray {
+    fn name() -> ByteArray {
         "OnlyKeyModel"
     }
 
     #[inline(always)]
-    fn version(self: @OnlyKeyModel) -> u8 {
+    fn version() -> u8 {
         1
     }
 
     #[inline(always)]
-    fn selector(self: @OnlyKeyModel) -> felt252 {
+    fn selector() -> felt252 {
         selector!("OnlyKeyModel")
     }
 
+    #[inline(always)]
+    fn instance_selector(self: @OnlyKeyModel) -> felt252 {
+        dojo::model::Model::<OnlyKeyModel>::selector()
+    }
+
     #[inline(always)]
     fn keys(self: @OnlyKeyModel) -> Span<felt252> {
         let mut serialized = core::array::ArrayTrait::new();
@@ -2160,16 +2360,29 @@ impl OnlyKeyModelModel of dojo::model::Model<OnlyKeyModel> {
     }
 
     #[inline(always)]
-    fn layout(self: @OnlyKeyModel) -> Span<u8> {
+    fn layout() -> dojo::model::ModelLayout {
         let mut layout = core::array::ArrayTrait::new();
         dojo::database::introspect::Introspect::<OnlyKeyModel>::layout(ref layout);
-        core::array::ArrayTrait::span(@layout)
+        dojo::model::ModelLayout::Serial(core::array::ArrayTrait::span(@layout))
     }
 
     #[inline(always)]
-    fn packed_size(self: @OnlyKeyModel) -> usize {
-        let mut layout = self.layout();
-        dojo::packing::calculate_packed_size(ref layout)
+    fn instance_layout(self: @OnlyKeyModel) -> dojo::model::ModelLayout {
+        dojo::model::Model::<OnlyKeyModel>::layout()
+    }
+
+    #[inline(always)]
+    fn packed_size() -> usize {
+        match dojo::model::Model::<OnlyKeyModel>::layout() {
+            dojo::model::ModelLayout::Serial(layout) => {
+                let mut layout = layout.clone();
+                dojo::packing::calculate_packed_size(ref layout)
+            },
+            _ => {
+                panic!("Unexpected error");
+                0
+            }
+        }
     }
 }
 
@@ -2189,15 +2402,15 @@ mod only_key_model {
     #[abi(embed_v0)]
     impl DojoModelImpl of dojo::model::IModel<ContractState>{
         fn selector(self: @ContractState) -> felt252 {
-            selector!("OnlyKeyModel")
+           dojo::model::Model::<OnlyKeyModel>::selector()
         }
 
         fn name(self: @ContractState) -> ByteArray {
-            "OnlyKeyModel"
+           dojo::model::Model::<OnlyKeyModel>::name()
         }
 
         fn version(self: @ContractState) -> u8 {
-            1
+           dojo::model::Model::<OnlyKeyModel>::version()
         }
 
         fn unpacked_size(self: @ContractState) -> usize {
@@ -2205,16 +2418,11 @@ mod only_key_model {
         }
 
         fn packed_size(self: @ContractState) -> usize {
-            let mut layout = core::array::ArrayTrait::new();
-            dojo::database::introspect::Introspect::<OnlyKeyModel>::layout(ref layout);
-            let mut layout_span = layout.span();
-            dojo::packing::calculate_packed_size(ref layout_span)
+            dojo::model::Model::<OnlyKeyModel>::packed_size()
         }
 
-        fn layout(self: @ContractState) -> Span<u8> {
-            let mut layout = core::array::ArrayTrait::new();
-            dojo::database::introspect::Introspect::<OnlyKeyModel>::layout(ref layout);
-            core::array::ArrayTrait::span(@layout)
+        fn layout(self: @ContractState) -> dojo::model::ModelLayout {
+            dojo::model::Model::<OnlyKeyModel>::layout()
         }
 
         fn schema(self: @ContractState) -> dojo::database::introspect::Ty {
@@ -2230,7 +2438,7 @@ mod only_key_model {
 }
 
 impl U256KeyModelModel of dojo::model::Model<U256KeyModel> {
-    fn entity(world: dojo::world::IWorldDispatcher, keys: Span<felt252>, layout: Span<u8>) -> U256KeyModel {
+    fn entity(world: dojo::world::IWorldDispatcher, keys: Span<felt252>, layout: dojo::model::ModelLayout) -> U256KeyModel {
         let values = dojo::world::IWorldDispatcherTrait::entity(world, selector!("U256KeyModel"), keys, layout);
 
         // TODO: Generate method to deserialize from keys / values directly to avoid
@@ -2252,20 +2460,25 @@ impl U256KeyModelModel of dojo::model::Model<U256KeyModel> {
     }
 
     #[inline(always)]
-    fn name(self: @U256KeyModel) -> ByteArray {
+    fn name() -> ByteArray {
         "U256KeyModel"
     }
 
     #[inline(always)]
-    fn version(self: @U256KeyModel) -> u8 {
+    fn version() -> u8 {
         1
     }
 
     #[inline(always)]
-    fn selector(self: @U256KeyModel) -> felt252 {
+    fn selector() -> felt252 {
         selector!("U256KeyModel")
     }
 
+    #[inline(always)]
+    fn instance_selector(self: @U256KeyModel) -> felt252 {
+        dojo::model::Model::<U256KeyModel>::selector()
+    }
+
     #[inline(always)]
     fn keys(self: @U256KeyModel) -> Span<felt252> {
         let mut serialized = core::array::ArrayTrait::new();
@@ -2281,16 +2494,29 @@ impl U256KeyModelModel of dojo::model::Model<U256KeyModel> {
     }
 
     #[inline(always)]
-    fn layout(self: @U256KeyModel) -> Span<u8> {
+    fn layout() -> dojo::model::ModelLayout {
         let mut layout = core::array::ArrayTrait::new();
         dojo::database::introspect::Introspect::<U256KeyModel>::layout(ref layout);
-        core::array::ArrayTrait::span(@layout)
+        dojo::model::ModelLayout::Serial(core::array::ArrayTrait::span(@layout))
     }
 
     #[inline(always)]
-    fn packed_size(self: @U256KeyModel) -> usize {
-        let mut layout = self.layout();
-        dojo::packing::calculate_packed_size(ref layout)
+    fn instance_layout(self: @U256KeyModel) -> dojo::model::ModelLayout {
+        dojo::model::Model::<U256KeyModel>::layout()
+    }
+
+    #[inline(always)]
+    fn packed_size() -> usize {
+        match dojo::model::Model::<U256KeyModel>::layout() {
+            dojo::model::ModelLayout::Serial(layout) => {
+                let mut layout = layout.clone();
+                dojo::packing::calculate_packed_size(ref layout)
+            },
+            _ => {
+                panic!("Unexpected error");
+                0
+            }
+        }
     }
 }
 
@@ -2310,15 +2536,15 @@ mod u_256_key_model {
     #[abi(embed_v0)]
     impl DojoModelImpl of dojo::model::IModel<ContractState>{
         fn selector(self: @ContractState) -> felt252 {
-            selector!("U256KeyModel")
+           dojo::model::Model::<U256KeyModel>::selector()
         }
 
         fn name(self: @ContractState) -> ByteArray {
-            "U256KeyModel"
+           dojo::model::Model::<U256KeyModel>::name()
         }
 
         fn version(self: @ContractState) -> u8 {
-            1
+           dojo::model::Model::<U256KeyModel>::version()
         }
 
         fn unpacked_size(self: @ContractState) -> usize {
@@ -2326,16 +2552,11 @@ mod u_256_key_model {
         }
 
         fn packed_size(self: @ContractState) -> usize {
-            let mut layout = core::array::ArrayTrait::new();
-            dojo::database::introspect::Introspect::<U256KeyModel>::layout(ref layout);
-            let mut layout_span = layout.span();
-            dojo::packing::calculate_packed_size(ref layout_span)
+            dojo::model::Model::<U256KeyModel>::packed_size()
         }
 
-        fn layout(self: @ContractState) -> Span<u8> {
-            let mut layout = core::array::ArrayTrait::new();
-            dojo::database::introspect::Introspect::<U256KeyModel>::layout(ref layout);
-            core::array::ArrayTrait::span(@layout)
+        fn layout(self: @ContractState) -> dojo::model::ModelLayout {
+            dojo::model::Model::<U256KeyModel>::layout()
         }
 
         fn schema(self: @ContractState) -> dojo::database::introspect::Ty {
@@ -2351,7 +2572,7 @@ mod u_256_key_model {
 }
 
 impl PlayerModel of dojo::model::Model<Player> {
-    fn entity(world: dojo::world::IWorldDispatcher, keys: Span<felt252>, layout: Span<u8>) -> Player {
+    fn entity(world: dojo::world::IWorldDispatcher, keys: Span<felt252>, layout: dojo::model::ModelLayout) -> Player {
         let values = dojo::world::IWorldDispatcherTrait::entity(world, selector!("Player"), keys, layout);
 
         // TODO: Generate method to deserialize from keys / values directly to avoid
@@ -2373,20 +2594,25 @@ impl PlayerModel of dojo::model::Model<Player> {
     }
 
     #[inline(always)]
-    fn name(self: @Player) -> ByteArray {
+    fn name() -> ByteArray {
         "Player"
     }
 
     #[inline(always)]
-    fn version(self: @Player) -> u8 {
+    fn version() -> u8 {
         1
     }
 
     #[inline(always)]
-    fn selector(self: @Player) -> felt252 {
+    fn selector() -> felt252 {
         selector!("Player")
     }
 
+    #[inline(always)]
+    fn instance_selector(self: @Player) -> felt252 {
+        dojo::model::Model::<Player>::selector()
+    }
+
     #[inline(always)]
     fn keys(self: @Player) -> Span<felt252> {
         let mut serialized = core::array::ArrayTrait::new();
@@ -2402,16 +2628,29 @@ impl PlayerModel of dojo::model::Model<Player> {
     }
 
     #[inline(always)]
-    fn layout(self: @Player) -> Span<u8> {
+    fn layout() -> dojo::model::ModelLayout {
         let mut layout = core::array::ArrayTrait::new();
         dojo::database::introspect::Introspect::<Player>::layout(ref layout);
-        core::array::ArrayTrait::span(@layout)
+        dojo::model::ModelLayout::Serial(core::array::ArrayTrait::span(@layout))
     }
 
     #[inline(always)]
-    fn packed_size(self: @Player) -> usize {
-        let mut layout = self.layout();
-        dojo::packing::calculate_packed_size(ref layout)
+    fn instance_layout(self: @Player) -> dojo::model::ModelLayout {
+        dojo::model::Model::<Player>::layout()
+    }
+
+    #[inline(always)]
+    fn packed_size() -> usize {
+        match dojo::model::Model::<Player>::layout() {
+            dojo::model::ModelLayout::Serial(layout) => {
+                let mut layout = layout.clone();
+                dojo::packing::calculate_packed_size(ref layout)
+            },
+            _ => {
+                panic!("Unexpected error");
+                0
+            }
+        }
     }
 }
 
@@ -2431,15 +2670,15 @@ mod player {
     #[abi(embed_v0)]
     impl DojoModelImpl of dojo::model::IModel<ContractState>{
         fn selector(self: @ContractState) -> felt252 {
-            selector!("Player")
+           dojo::model::Model::<Player>::selector()
         }
 
         fn name(self: @ContractState) -> ByteArray {
-            "Player"
+           dojo::model::Model::<Player>::name()
         }
 
         fn version(self: @ContractState) -> u8 {
-            1
+           dojo::model::Model::<Player>::version()
         }
 
         fn unpacked_size(self: @ContractState) -> usize {
@@ -2447,16 +2686,11 @@ mod player {
         }
 
         fn packed_size(self: @ContractState) -> usize {
-            let mut layout = core::array::ArrayTrait::new();
-            dojo::database::introspect::Introspect::<Player>::layout(ref layout);
-            let mut layout_span = layout.span();
-            dojo::packing::calculate_packed_size(ref layout_span)
+            dojo::model::Model::<Player>::packed_size()
         }
 
-        fn layout(self: @ContractState) -> Span<u8> {
-            let mut layout = core::array::ArrayTrait::new();
-            dojo::database::introspect::Introspect::<Player>::layout(ref layout);
-            core::array::ArrayTrait::span(@layout)
+        fn layout(self: @ContractState) -> dojo::model::ModelLayout {
+            dojo::model::Model::<Player>::layout()
         }
 
         fn schema(self: @ContractState) -> dojo::database::introspect::Ty {
@@ -2553,361 +2787,361 @@ struct U256KeyModel {
        ^**********^
 
 error: Unsupported attribute.
- --> test_src/lib.cairo[BadModelMultipleVersions]:72:1
+ --> test_src/lib.cairo[BadModelMultipleVersions]:90:1
 #[starknet::contract]
 ^*******************^
 
 error: Unsupported attribute.
- --> test_src/lib.cairo[BadModelBadVersionType]:72:1
+ --> test_src/lib.cairo[BadModelBadVersionType]:90:1
 #[starknet::contract]
 ^*******************^
 
 error: Unsupported attribute.
- --> test_src/lib.cairo[BadModelNoVersionValue]:72:1
+ --> test_src/lib.cairo[BadModelNoVersionValue]:90:1
 #[starknet::contract]
 ^*******************^
 
 error: Unsupported attribute.
- --> test_src/lib.cairo[BadModelUnexpectedArgWithValue]:72:1
+ --> test_src/lib.cairo[BadModelUnexpectedArgWithValue]:90:1
 #[starknet::contract]
 ^*******************^
 
 error: Unsupported attribute.
- --> test_src/lib.cairo[BadModelUnexpectedArg]:72:1
+ --> test_src/lib.cairo[BadModelUnexpectedArg]:90:1
 #[starknet::contract]
 ^*******************^
 
 error: Unsupported attribute.
- --> test_src/lib.cairo[BadModelNotSupportedVersion]:72:1
+ --> test_src/lib.cairo[BadModelNotSupportedVersion]:90:1
 #[starknet::contract]
 ^*******************^
 
 error: Unsupported attribute.
- --> test_src/lib.cairo[BadModelMultipleLayouts]:72:1
+ --> test_src/lib.cairo[BadModelMultipleLayouts]:90:1
 #[starknet::contract]
 ^*******************^
 
 error: Unsupported attribute.
- --> test_src/lib.cairo[BadModelBadLayoutType]:72:1
+ --> test_src/lib.cairo[BadModelBadLayoutType]:90:1
 #[starknet::contract]
 ^*******************^
 
 error: Unsupported attribute.
- --> test_src/lib.cairo[BadModelNoLayoutValue]:72:1
+ --> test_src/lib.cairo[BadModelNoLayoutValue]:90:1
 #[starknet::contract]
 ^*******************^
 
 error: Unsupported attribute.
- --> test_src/lib.cairo[BadModelNotSupportedLayout]:72:1
+ --> test_src/lib.cairo[BadModelNotSupportedLayout]:90:1
 #[starknet::contract]
 ^*******************^
 
 error: Unsupported attribute.
- --> test_src/lib.cairo[Modelv0]:72:1
+ --> test_src/lib.cairo[Modelv0]:90:1
 #[starknet::contract]
 ^*******************^
 
 error: Unsupported attribute.
- --> test_src/lib.cairo[ModelSerialShortString]:72:1
+ --> test_src/lib.cairo[ModelSerialShortString]:90:1
 #[starknet::contract]
 ^*******************^
 
 error: Unsupported attribute.
- --> test_src/lib.cairo[ModelSerialString]:72:1
+ --> test_src/lib.cairo[ModelSerialString]:90:1
 #[starknet::contract]
 ^*******************^
 
 error: Unsupported attribute.
- --> test_src/lib.cairo[Position]:72:1
+ --> test_src/lib.cairo[Position]:90:1
 #[starknet::contract]
 ^*******************^
 
 error: Unsupported attribute.
- --> test_src/lib.cairo[Roles]:72:1
+ --> test_src/lib.cairo[Roles]:90:1
 #[starknet::contract]
 ^*******************^
 
 error: Unsupported attribute.
- --> test_src/lib.cairo[OnlyKeyModel]:72:1
+ --> test_src/lib.cairo[OnlyKeyModel]:90:1
 #[starknet::contract]
 ^*******************^
 
 error: Unsupported attribute.
- --> test_src/lib.cairo[U256KeyModel]:72:1
+ --> test_src/lib.cairo[U256KeyModel]:90:1
 #[starknet::contract]
 ^*******************^
 
 error: Unsupported attribute.
- --> test_src/lib.cairo[Player]:72:1
+ --> test_src/lib.cairo[Player]:90:1
 #[starknet::contract]
 ^*******************^
 
 error: Unsupported attribute.
- --> test_src/lib.cairo[BadModelMultipleVersions]:77:5
+ --> test_src/lib.cairo[BadModelMultipleVersions]:95:5
     #[storage]
     ^********^
 
 error: Unsupported attribute.
- --> test_src/lib.cairo[BadModelMultipleVersions]:80:5
+ --> test_src/lib.cairo[BadModelMultipleVersions]:98:5
     #[abi(embed_v0)]
     ^**************^
 
 error: Unsupported attribute.
- --> test_src/lib.cairo[BadModelMultipleVersions]:116:5
+ --> test_src/lib.cairo[BadModelMultipleVersions]:129:5
     #[abi(embed_v0)]
     ^**************^
 
 error: Unsupported attribute.
- --> test_src/lib.cairo[BadModelBadVersionType]:77:5
+ --> test_src/lib.cairo[BadModelBadVersionType]:95:5
     #[storage]
     ^********^
 
 error: Unsupported attribute.
- --> test_src/lib.cairo[BadModelBadVersionType]:80:5
+ --> test_src/lib.cairo[BadModelBadVersionType]:98:5
     #[abi(embed_v0)]
     ^**************^
 
 error: Unsupported attribute.
- --> test_src/lib.cairo[BadModelBadVersionType]:116:5
+ --> test_src/lib.cairo[BadModelBadVersionType]:129:5
     #[abi(embed_v0)]
     ^**************^
 
 error: Unsupported attribute.
- --> test_src/lib.cairo[BadModelNoVersionValue]:77:5
+ --> test_src/lib.cairo[BadModelNoVersionValue]:95:5
     #[storage]
     ^********^
 
 error: Unsupported attribute.
- --> test_src/lib.cairo[BadModelNoVersionValue]:80:5
+ --> test_src/lib.cairo[BadModelNoVersionValue]:98:5
     #[abi(embed_v0)]
     ^**************^
 
 error: Unsupported attribute.
- --> test_src/lib.cairo[BadModelNoVersionValue]:116:5
+ --> test_src/lib.cairo[BadModelNoVersionValue]:129:5
     #[abi(embed_v0)]
     ^**************^
 
 error: Unsupported attribute.
- --> test_src/lib.cairo[BadModelUnexpectedArgWithValue]:77:5
+ --> test_src/lib.cairo[BadModelUnexpectedArgWithValue]:95:5
     #[storage]
     ^********^
 
 error: Unsupported attribute.
- --> test_src/lib.cairo[BadModelUnexpectedArgWithValue]:80:5
+ --> test_src/lib.cairo[BadModelUnexpectedArgWithValue]:98:5
     #[abi(embed_v0)]
     ^**************^
 
 error: Unsupported attribute.
- --> test_src/lib.cairo[BadModelUnexpectedArgWithValue]:116:5
+ --> test_src/lib.cairo[BadModelUnexpectedArgWithValue]:129:5
     #[abi(embed_v0)]
     ^**************^
 
 error: Unsupported attribute.
- --> test_src/lib.cairo[BadModelUnexpectedArg]:77:5
+ --> test_src/lib.cairo[BadModelUnexpectedArg]:95:5
     #[storage]
     ^********^
 
 error: Unsupported attribute.
- --> test_src/lib.cairo[BadModelUnexpectedArg]:80:5
+ --> test_src/lib.cairo[BadModelUnexpectedArg]:98:5
     #[abi(embed_v0)]
     ^**************^
 
 error: Unsupported attribute.
- --> test_src/lib.cairo[BadModelUnexpectedArg]:116:5
+ --> test_src/lib.cairo[BadModelUnexpectedArg]:129:5
     #[abi(embed_v0)]
     ^**************^
 
 error: Unsupported attribute.
- --> test_src/lib.cairo[BadModelNotSupportedVersion]:77:5
+ --> test_src/lib.cairo[BadModelNotSupportedVersion]:95:5
     #[storage]
     ^********^
 
 error: Unsupported attribute.
- --> test_src/lib.cairo[BadModelNotSupportedVersion]:80:5
+ --> test_src/lib.cairo[BadModelNotSupportedVersion]:98:5
     #[abi(embed_v0)]
     ^**************^
 
 error: Unsupported attribute.
- --> test_src/lib.cairo[BadModelNotSupportedVersion]:116:5
+ --> test_src/lib.cairo[BadModelNotSupportedVersion]:129:5
     #[abi(embed_v0)]
     ^**************^
 
 error: Unsupported attribute.
- --> test_src/lib.cairo[BadModelMultipleLayouts]:77:5
+ --> test_src/lib.cairo[BadModelMultipleLayouts]:95:5
     #[storage]
     ^********^
 
 error: Unsupported attribute.
- --> test_src/lib.cairo[BadModelMultipleLayouts]:80:5
+ --> test_src/lib.cairo[BadModelMultipleLayouts]:98:5
     #[abi(embed_v0)]
     ^**************^
 
 error: Unsupported attribute.
- --> test_src/lib.cairo[BadModelMultipleLayouts]:116:5
+ --> test_src/lib.cairo[BadModelMultipleLayouts]:129:5
     #[abi(embed_v0)]
     ^**************^
 
 error: Unsupported attribute.
- --> test_src/lib.cairo[BadModelBadLayoutType]:77:5
+ --> test_src/lib.cairo[BadModelBadLayoutType]:95:5
     #[storage]
     ^********^
 
 error: Unsupported attribute.
- --> test_src/lib.cairo[BadModelBadLayoutType]:80:5
+ --> test_src/lib.cairo[BadModelBadLayoutType]:98:5
     #[abi(embed_v0)]
     ^**************^
 
 error: Unsupported attribute.
- --> test_src/lib.cairo[BadModelBadLayoutType]:116:5
+ --> test_src/lib.cairo[BadModelBadLayoutType]:129:5
     #[abi(embed_v0)]
     ^**************^
 
 error: Unsupported attribute.
- --> test_src/lib.cairo[BadModelNoLayoutValue]:77:5
+ --> test_src/lib.cairo[BadModelNoLayoutValue]:95:5
     #[storage]
     ^********^
 
 error: Unsupported attribute.
- --> test_src/lib.cairo[BadModelNoLayoutValue]:80:5
+ --> test_src/lib.cairo[BadModelNoLayoutValue]:98:5
     #[abi(embed_v0)]
     ^**************^
 
 error: Unsupported attribute.
- --> test_src/lib.cairo[BadModelNoLayoutValue]:116:5
+ --> test_src/lib.cairo[BadModelNoLayoutValue]:129:5
     #[abi(embed_v0)]
     ^**************^
 
 error: Unsupported attribute.
- --> test_src/lib.cairo[BadModelNotSupportedLayout]:77:5
+ --> test_src/lib.cairo[BadModelNotSupportedLayout]:95:5
     #[storage]
     ^********^
 
 error: Unsupported attribute.
- --> test_src/lib.cairo[BadModelNotSupportedLayout]:80:5
+ --> test_src/lib.cairo[BadModelNotSupportedLayout]:98:5
     #[abi(embed_v0)]
     ^**************^
 
 error: Unsupported attribute.
- --> test_src/lib.cairo[BadModelNotSupportedLayout]:116:5
+ --> test_src/lib.cairo[BadModelNotSupportedLayout]:129:5
     #[abi(embed_v0)]
     ^**************^
 
 error: Unsupported attribute.
- --> test_src/lib.cairo[Modelv0]:77:5
+ --> test_src/lib.cairo[Modelv0]:95:5
     #[storage]
     ^********^
 
 error: Unsupported attribute.
- --> test_src/lib.cairo[Modelv0]:80:5
+ --> test_src/lib.cairo[Modelv0]:98:5
     #[abi(embed_v0)]
     ^**************^
 
 error: Unsupported attribute.
- --> test_src/lib.cairo[Modelv0]:116:5
+ --> test_src/lib.cairo[Modelv0]:129:5
     #[abi(embed_v0)]
     ^**************^
 
 error: Unsupported attribute.
- --> test_src/lib.cairo[ModelSerialShortString]:77:5
+ --> test_src/lib.cairo[ModelSerialShortString]:95:5
     #[storage]
     ^********^
 
 error: Unsupported attribute.
- --> test_src/lib.cairo[ModelSerialShortString]:80:5
+ --> test_src/lib.cairo[ModelSerialShortString]:98:5
     #[abi(embed_v0)]
     ^**************^
 
 error: Unsupported attribute.
- --> test_src/lib.cairo[ModelSerialShortString]:116:5
+ --> test_src/lib.cairo[ModelSerialShortString]:129:5
     #[abi(embed_v0)]
     ^**************^
 
 error: Unsupported attribute.
- --> test_src/lib.cairo[ModelSerialString]:77:5
+ --> test_src/lib.cairo[ModelSerialString]:95:5
     #[storage]
     ^********^
 
 error: Unsupported attribute.
- --> test_src/lib.cairo[ModelSerialString]:80:5
+ --> test_src/lib.cairo[ModelSerialString]:98:5
     #[abi(embed_v0)]
     ^**************^
 
 error: Unsupported attribute.
- --> test_src/lib.cairo[ModelSerialString]:116:5
+ --> test_src/lib.cairo[ModelSerialString]:129:5
     #[abi(embed_v0)]
     ^**************^
 
 error: Unsupported attribute.
- --> test_src/lib.cairo[Position]:77:5
+ --> test_src/lib.cairo[Position]:95:5
     #[storage]
     ^********^
 
 error: Unsupported attribute.
- --> test_src/lib.cairo[Position]:80:5
+ --> test_src/lib.cairo[Position]:98:5
     #[abi(embed_v0)]
     ^**************^
 
 error: Unsupported attribute.
- --> test_src/lib.cairo[Position]:116:5
+ --> test_src/lib.cairo[Position]:129:5
     #[abi(embed_v0)]
     ^**************^
 
 error: Unsupported attribute.
- --> test_src/lib.cairo[Roles]:77:5
+ --> test_src/lib.cairo[Roles]:95:5
     #[storage]
     ^********^
 
 error: Unsupported attribute.
- --> test_src/lib.cairo[Roles]:80:5
+ --> test_src/lib.cairo[Roles]:98:5
     #[abi(embed_v0)]
     ^**************^
 
 error: Unsupported attribute.
- --> test_src/lib.cairo[Roles]:116:5
+ --> test_src/lib.cairo[Roles]:129:5
     #[abi(embed_v0)]
     ^**************^
 
 error: Unsupported attribute.
- --> test_src/lib.cairo[OnlyKeyModel]:77:5
+ --> test_src/lib.cairo[OnlyKeyModel]:95:5
     #[storage]
     ^********^
 
 error: Unsupported attribute.
- --> test_src/lib.cairo[OnlyKeyModel]:80:5
+ --> test_src/lib.cairo[OnlyKeyModel]:98:5
     #[abi(embed_v0)]
     ^**************^
 
 error: Unsupported attribute.
- --> test_src/lib.cairo[OnlyKeyModel]:116:5
+ --> test_src/lib.cairo[OnlyKeyModel]:129:5
     #[abi(embed_v0)]
     ^**************^
 
 error: Unsupported attribute.
- --> test_src/lib.cairo[U256KeyModel]:77:5
+ --> test_src/lib.cairo[U256KeyModel]:95:5
     #[storage]
     ^********^
 
 error: Unsupported attribute.
- --> test_src/lib.cairo[U256KeyModel]:80:5
+ --> test_src/lib.cairo[U256KeyModel]:98:5
     #[abi(embed_v0)]
     ^**************^
 
 error: Unsupported attribute.
- --> test_src/lib.cairo[U256KeyModel]:116:5
+ --> test_src/lib.cairo[U256KeyModel]:129:5
     #[abi(embed_v0)]
     ^**************^
 
 error: Unsupported attribute.
- --> test_src/lib.cairo[Player]:77:5
+ --> test_src/lib.cairo[Player]:95:5
     #[storage]
     ^********^
 
 error: Unsupported attribute.
- --> test_src/lib.cairo[Player]:80:5
+ --> test_src/lib.cairo[Player]:98:5
     #[abi(embed_v0)]
     ^**************^
 
 error: Unsupported attribute.
- --> test_src/lib.cairo[Player]:116:5
+ --> test_src/lib.cairo[Player]:129:5
     #[abi(embed_v0)]
     ^**************^
diff --git a/crates/dojo-lang/src/plugin_test_data/system b/crates/dojo-lang/src/plugin_test_data/system
index e9ce18bde4..6673499c1e 100644
--- a/crates/dojo-lang/src/plugin_test_data/system
+++ b/crates/dojo-lang/src/plugin_test_data/system
@@ -400,162 +400,162 @@ error: Unsupported attribute.
     ^********^
 
 error: Unknown inline item macro: 'component'.
- --> test_src/lib.cairo[spawn]:10:21
+ --> test_src/lib.cairo[spawn]:11:21
                     component!(path: dojo::components::upgradeable::upgradeable, storage: upgradeable, event: UpgradeableEvent);
                     ^**********************************************************************************************************^
 
 error: Unsupported attribute.
- --> test_src/lib.cairo[spawn]:12:21
+ --> test_src/lib.cairo[spawn]:13:21
                     #[abi(embed_v0)]
                     ^**************^
 
 error: Unsupported attribute.
- --> test_src/lib.cairo[spawn]:19:21
+ --> test_src/lib.cairo[spawn]:20:21
                     #[abi(embed_v0)]
                     ^**************^
 
 error: Unsupported attribute.
- --> test_src/lib.cairo[spawn]:26:21
+ --> test_src/lib.cairo[spawn]:27:21
                     #[abi(embed_v0)]
                     ^**************^
 
 error: Unsupported attribute.
- --> test_src/lib.cairo[spawn]:36:13
+ --> test_src/lib.cairo[spawn]:37:13
             #[event]
             ^******^
 
 error: Unsupported attribute.
- --> test_src/lib.cairo[spawn]:42:13
+ --> test_src/lib.cairo[spawn]:43:13
             #[storage]
             ^********^
 
 error: Unsupported attribute.
- --> test_src/lib.cairo[spawn]:45:17
+ --> test_src/lib.cairo[spawn]:46:17
                 #[substorage(v0)]
                 ^***************^
 
 error: Unknown inline item macro: 'component'.
- --> test_src/lib.cairo[proxy]:10:21
+ --> test_src/lib.cairo[proxy]:11:21
                     component!(path: dojo::components::upgradeable::upgradeable, storage: upgradeable, event: UpgradeableEvent);
                     ^**********************************************************************************************************^
 
 error: Unsupported attribute.
- --> test_src/lib.cairo[proxy]:12:21
+ --> test_src/lib.cairo[proxy]:13:21
                     #[abi(embed_v0)]
                     ^**************^
 
 error: Unsupported attribute.
- --> test_src/lib.cairo[proxy]:19:21
+ --> test_src/lib.cairo[proxy]:20:21
                     #[abi(embed_v0)]
                     ^**************^
 
 error: Unsupported attribute.
- --> test_src/lib.cairo[proxy]:26:21
+ --> test_src/lib.cairo[proxy]:27:21
                     #[abi(embed_v0)]
                     ^**************^
 
 error: Unsupported attribute.
- --> test_src/lib.cairo[proxy]:33:13
+ --> test_src/lib.cairo[proxy]:34:13
             #[event]
             ^******^
 
 error: Unsupported attribute.
- --> test_src/lib.cairo[proxy]:39:13
+ --> test_src/lib.cairo[proxy]:40:13
             #[storage]
             ^********^
 
 error: Unsupported attribute.
- --> test_src/lib.cairo[proxy]:42:17
+ --> test_src/lib.cairo[proxy]:43:17
                 #[substorage(v0)]
                 ^***************^
 
 error: Unknown inline item macro: 'component'.
- --> test_src/lib.cairo[ctxnamed]:10:21
+ --> test_src/lib.cairo[ctxnamed]:11:21
                     component!(path: dojo::components::upgradeable::upgradeable, storage: upgradeable, event: UpgradeableEvent);
                     ^**********************************************************************************************************^
 
 error: Unsupported attribute.
- --> test_src/lib.cairo[ctxnamed]:12:21
+ --> test_src/lib.cairo[ctxnamed]:13:21
                     #[abi(embed_v0)]
                     ^**************^
 
 error: Unsupported attribute.
- --> test_src/lib.cairo[ctxnamed]:19:21
+ --> test_src/lib.cairo[ctxnamed]:20:21
                     #[abi(embed_v0)]
                     ^**************^
 
 error: Unsupported attribute.
- --> test_src/lib.cairo[ctxnamed]:26:21
+ --> test_src/lib.cairo[ctxnamed]:27:21
                     #[abi(embed_v0)]
                     ^**************^
 
 error: Unsupported attribute.
- --> test_src/lib.cairo[ctxnamed]:36:13
+ --> test_src/lib.cairo[ctxnamed]:37:13
             #[event]
             ^******^
 
 error: Unsupported attribute.
- --> test_src/lib.cairo[ctxnamed]:42:13
+ --> test_src/lib.cairo[ctxnamed]:43:13
             #[storage]
             ^********^
 
 error: Unsupported attribute.
- --> test_src/lib.cairo[ctxnamed]:45:17
+ --> test_src/lib.cairo[ctxnamed]:46:17
                 #[substorage(v0)]
                 ^***************^
 
 error: Unknown inline item macro: 'component'.
- --> test_src/lib.cairo[withevent]:10:21
+ --> test_src/lib.cairo[withevent]:11:21
                     component!(path: dojo::components::upgradeable::upgradeable, storage: upgradeable, event: UpgradeableEvent);
                     ^**********************************************************************************************************^
 
 error: Unsupported attribute.
- --> test_src/lib.cairo[withevent]:12:21
+ --> test_src/lib.cairo[withevent]:13:21
                     #[abi(embed_v0)]
                     ^**************^
 
 error: Unsupported attribute.
- --> test_src/lib.cairo[withevent]:19:21
+ --> test_src/lib.cairo[withevent]:20:21
                     #[abi(embed_v0)]
                     ^**************^
 
 error: Unsupported attribute.
- --> test_src/lib.cairo[withevent]:26:21
+ --> test_src/lib.cairo[withevent]:27:21
                     #[abi(embed_v0)]
                     ^**************^
 
 error: Unsupported attribute.
- --> test_src/lib.cairo[withevent]:30:13
+ --> test_src/lib.cairo[withevent]:31:13
             #[event]
             ^******^
 
 error: Unsupported attribute.
- --> test_src/lib.cairo[withevent]:42:13
+ --> test_src/lib.cairo[withevent]:43:13
             #[storage]
             ^********^
 
 error: Unsupported attribute.
- --> test_src/lib.cairo[withevent]:45:17
+ --> test_src/lib.cairo[withevent]:46:17
                 #[substorage(v0)]
                 ^***************^
 
 error: Unknown inline item macro: 'component'.
- --> test_src/lib.cairo[withcomponent]:10:21
+ --> test_src/lib.cairo[withcomponent]:11:21
                     component!(path: dojo::components::upgradeable::upgradeable, storage: upgradeable, event: UpgradeableEvent);
                     ^**********************************************************************************************************^
 
 error: Unsupported attribute.
- --> test_src/lib.cairo[withcomponent]:12:21
+ --> test_src/lib.cairo[withcomponent]:13:21
                     #[abi(embed_v0)]
                     ^**************^
 
 error: Unsupported attribute.
- --> test_src/lib.cairo[withcomponent]:19:21
+ --> test_src/lib.cairo[withcomponent]:20:21
                     #[abi(embed_v0)]
                     ^**************^
 
 error: Unsupported attribute.
- --> test_src/lib.cairo[withcomponent]:26:21
+ --> test_src/lib.cairo[withcomponent]:27:21
                     #[abi(embed_v0)]
                     ^**************^
 
@@ -570,52 +570,52 @@ error: Unknown inline item macro: 'component'.
     ^*********************************************************************************************^
 
 error: Unsupported attribute.
- --> test_src/lib.cairo[withcomponent]:32:13
+ --> test_src/lib.cairo[withcomponent]:33:13
             #[storage]
             ^********^
 
 error: Unsupported attribute.
- --> test_src/lib.cairo[withcomponent]:35:17
+ --> test_src/lib.cairo[withcomponent]:36:17
                 #[substorage(v0)]
                 ^***************^
 
 error: Unsupported attribute.
- --> test_src/lib.cairo[withcomponent]:37:25
+ --> test_src/lib.cairo[withcomponent]:38:25
                         #[substorage(v0)]
                         ^***************^
 
 error: Unsupported attribute.
- --> test_src/lib.cairo[withcomponent]:39:9
+ --> test_src/lib.cairo[withcomponent]:40:9
         #[substorage(v0)]
         ^***************^
 
 error: Unsupported attribute.
- --> test_src/lib.cairo[withcomponent]:43:13
+ --> test_src/lib.cairo[withcomponent]:44:13
             #[event]
             ^******^
 
 error: Unsupported attribute.
- --> test_src/lib.cairo[withcomponent]:47:25
+ --> test_src/lib.cairo[withcomponent]:48:25
                         #[flat]
                         ^*****^
 
 error: Unknown inline item macro: 'component'.
- --> test_src/lib.cairo[MyFaultyContract]:10:21
+ --> test_src/lib.cairo[MyFaultyContract]:11:21
                     component!(path: dojo::components::upgradeable::upgradeable, storage: upgradeable, event: UpgradeableEvent);
                     ^**********************************************************************************************************^
 
 error: Unsupported attribute.
- --> test_src/lib.cairo[MyFaultyContract]:12:21
+ --> test_src/lib.cairo[MyFaultyContract]:13:21
                     #[abi(embed_v0)]
                     ^**************^
 
 error: Unsupported attribute.
- --> test_src/lib.cairo[MyFaultyContract]:19:21
+ --> test_src/lib.cairo[MyFaultyContract]:20:21
                     #[abi(embed_v0)]
                     ^**************^
 
 error: Unsupported attribute.
- --> test_src/lib.cairo[MyFaultyContract]:26:21
+ --> test_src/lib.cairo[MyFaultyContract]:27:21
                     #[abi(embed_v0)]
                     ^**************^
 
@@ -625,37 +625,37 @@ error: Unsupported attribute.
     ^**************^
 
 error: Unsupported attribute.
- --> test_src/lib.cairo[MyFaultyContract]:60:13
+ --> test_src/lib.cairo[MyFaultyContract]:61:13
             #[event]
             ^******^
 
 error: Unsupported attribute.
- --> test_src/lib.cairo[MyFaultyContract]:66:13
+ --> test_src/lib.cairo[MyFaultyContract]:67:13
             #[storage]
             ^********^
 
 error: Unsupported attribute.
- --> test_src/lib.cairo[MyFaultyContract]:69:17
+ --> test_src/lib.cairo[MyFaultyContract]:70:17
                 #[substorage(v0)]
                 ^***************^
 
 error: Unknown inline item macro: 'component'.
- --> test_src/lib.cairo[MyNominalContract]:10:21
+ --> test_src/lib.cairo[MyNominalContract]:11:21
                     component!(path: dojo::components::upgradeable::upgradeable, storage: upgradeable, event: UpgradeableEvent);
                     ^**********************************************************************************************************^
 
 error: Unsupported attribute.
- --> test_src/lib.cairo[MyNominalContract]:12:21
+ --> test_src/lib.cairo[MyNominalContract]:13:21
                     #[abi(embed_v0)]
                     ^**************^
 
 error: Unsupported attribute.
- --> test_src/lib.cairo[MyNominalContract]:19:21
+ --> test_src/lib.cairo[MyNominalContract]:20:21
                     #[abi(embed_v0)]
                     ^**************^
 
 error: Unsupported attribute.
- --> test_src/lib.cairo[MyNominalContract]:26:21
+ --> test_src/lib.cairo[MyNominalContract]:27:21
                     #[abi(embed_v0)]
                     ^**************^
 
@@ -665,17 +665,17 @@ error: Unsupported attribute.
     ^**************^
 
 error: Unsupported attribute.
- --> test_src/lib.cairo[MyNominalContract]:64:13
+ --> test_src/lib.cairo[MyNominalContract]:65:13
             #[event]
             ^******^
 
 error: Unsupported attribute.
- --> test_src/lib.cairo[MyNominalContract]:70:13
+ --> test_src/lib.cairo[MyNominalContract]:71:13
             #[storage]
             ^********^
 
 error: Unsupported attribute.
- --> test_src/lib.cairo[MyNominalContract]:73:17
+ --> test_src/lib.cairo[MyNominalContract]:74:17
                 #[substorage(v0)]
                 ^***************^
 
diff --git a/crates/dojo-lang/src/semantics/test_data/get b/crates/dojo-lang/src/semantics/test_data/get
index e25825b0b4..71e1714908 100644
--- a/crates/dojo-lang/src/semantics/test_data/get
+++ b/crates/dojo-lang/src/semantics/test_data/get
@@ -198,49 +198,9 @@ Block(
                     ),
                     expr: FunctionCall(
                         ExprFunctionCall {
-                            function: ?7::new,
+                            function: ?7::layout,
                             args: [],
-                            ty: core::array::Array::<?8>,
-                        },
-                    ),
-                },
-            ),
-            Expr(
-                StatementExpr {
-                    expr: FunctionCall(
-                        ExprFunctionCall {
-                            function: ?8::layout,
-                            args: [
-                                Reference(
-                                    LocalVarId(test::__Health_layout__),
-                                ),
-                            ],
-                            ty: (),
-                        },
-                    ),
-                },
-            ),
-            Let(
-                StatementLet {
-                    pattern: Variable(
-                        __Health_layout_span__,
-                    ),
-                    expr: FunctionCall(
-                        ExprFunctionCall {
-                            function: ?9::span,
-                            args: [
-                                Value(
-                                    Snapshot(
-                                        ExprSnapshot {
-                                            inner: Var(
-                                                LocalVarId(test::__Health_layout__),
-                                            ),
-                                            ty: @core::array::Array::<core::integer::u8>,
-                                        },
-                                    ),
-                                ),
-                            ],
-                            ty: core::array::Span::<?9>,
+                            ty: dojo::model::ModelLayout,
                         },
                     ),
                 },
@@ -252,7 +212,7 @@ Block(
                     ),
                     expr: FunctionCall(
                         ExprFunctionCall {
-                            function: ?10::entity,
+                            function: ?8::entity,
                             args: [
                                 Value(
                                     Var(
@@ -266,11 +226,11 @@ Block(
                                 ),
                                 Value(
                                     Var(
-                                        LocalVarId(test::__Health_layout_span__),
+                                        LocalVarId(test::__Health_layout__),
                                     ),
                                 ),
                             ],
-                            ty: ?10,
+                            ty: ?8,
                         },
                     ),
                 },
@@ -287,6 +247,6 @@ Block(
 
 //! > semantic_diagnostics
 error: Trait has no implementation in context: dojo::model::Model::<test::Health>
- --> lib.cairo[get_inline_macro]:9:61
-                 let __Health: Health = dojo::model::Model::entity(world, __get_macro_keys__, __Health_layout_span__);
-                                                            ^****^
+ --> lib.cairo[get_inline_macro]:7:71
+                let __Health_layout__ = dojo::model::Model::<Health>::layout();
+                                                                      ^****^
diff --git a/crates/dojo-lang/src/semantics/test_data/set b/crates/dojo-lang/src/semantics/test_data/set
index dcd45073cd..6ac01efbb3 100644
--- a/crates/dojo-lang/src/semantics/test_data/set
+++ b/crates/dojo-lang/src/semantics/test_data/set
@@ -84,7 +84,7 @@ Block(
             Let(
                 StatementLet {
                     pattern: Variable(
-                        __set_macro_value__,
+                        __set_model_instance__,
                     ),
                     expr: StructCtor(
                         ExprStructCtor {
@@ -129,13 +129,13 @@ Block(
                                 Value(
                                     FunctionCall(
                                         ExprFunctionCall {
-                                            function: ?7::selector,
+                                            function: ?7::instance_selector,
                                             args: [
                                                 Value(
                                                     Snapshot(
                                                         ExprSnapshot {
                                                             inner: Var(
-                                                                LocalVarId(test::__set_macro_value__),
+                                                                LocalVarId(test::__set_model_instance__),
                                                             ),
                                                             ty: @test::Health,
                                                         },
@@ -155,7 +155,7 @@ Block(
                                                     Snapshot(
                                                         ExprSnapshot {
                                                             inner: Var(
-                                                                LocalVarId(test::__set_macro_value__),
+                                                                LocalVarId(test::__set_model_instance__),
                                                             ),
                                                             ty: @test::Health,
                                                         },
@@ -175,7 +175,7 @@ Block(
                                                     Snapshot(
                                                         ExprSnapshot {
                                                             inner: Var(
-                                                                LocalVarId(test::__set_macro_value__),
+                                                                LocalVarId(test::__set_model_instance__),
                                                             ),
                                                             ty: @test::Health,
                                                         },
@@ -189,20 +189,20 @@ Block(
                                 Value(
                                     FunctionCall(
                                         ExprFunctionCall {
-                                            function: ?10::layout,
+                                            function: ?10::instance_layout,
                                             args: [
                                                 Value(
                                                     Snapshot(
                                                         ExprSnapshot {
                                                             inner: Var(
-                                                                LocalVarId(test::__set_macro_value__),
+                                                                LocalVarId(test::__set_model_instance__),
                                                             ),
                                                             ty: @test::Health,
                                                         },
                                                     ),
                                                 ),
                                             ],
-                                            ty: core::array::Span::<core::integer::u8>,
+                                            ty: dojo::model::ModelLayout,
                                         },
                                     ),
                                 ),
@@ -225,6 +225,6 @@ fn test_func() { let key: felt252 = 0xb0b;
                      ^*^
 
 error: Trait has no implementation in context: dojo::model::Model::<test::Health>
- --> lib.cairo[set_inline_macro]:3:54
-                world.set_entity(dojo::model::Model::selector(@__set_macro_value__),
-                                                     ^******^
+ --> lib.cairo[set_inline_macro]:4:41
+                    dojo::model::Model::instance_selector(@__set_model_instance__),
+                                        ^***************^