diff --git a/crates/dojo-core/src/database/storage.cairo b/crates/dojo-core/src/database/storage.cairo
index 18bb054260..648ccfbbed 100644
--- a/crates/dojo-core/src/database/storage.cairo
+++ b/crates/dojo-core/src/database/storage.cairo
@@ -60,129 +60,3 @@ fn set_many(address_domain: u32, keys: Span<felt252>, offset: u8, mut value: Spa
         };
     };
 }
-
-
-trait StorageSize<T> {
-    fn unpacked_size() -> usize;
-    fn packed_size() -> usize;
-}
-
-impl StorageSizeFelt252 of StorageSize<felt252> {
-    #[inline(always)]
-    fn unpacked_size() -> usize {
-        1
-    }
-
-    #[inline(always)]
-    fn packed_size() -> usize {
-        252
-    }
-}
-
-impl StorageSizeBool of StorageSize<bool> {
-    #[inline(always)]
-    fn unpacked_size() -> usize {
-        1
-    }
-
-    #[inline(always)]
-    fn packed_size() -> usize {
-        1
-    }
-}
-
-impl StorageSizeU8 of StorageSize<u8> {
-    #[inline(always)]
-    fn unpacked_size() -> usize {
-        1
-    }
-
-    #[inline(always)]
-    fn packed_size() -> usize {
-        8
-    }
-}
-
-impl StorageSizeU16 of StorageSize<u16> {
-    #[inline(always)]
-    fn unpacked_size() -> usize {
-        1
-    }
-
-    #[inline(always)]
-    fn packed_size() -> usize {
-        16
-    }
-}
-
-impl StorageSizeU32 of StorageSize<u32> {
-    #[inline(always)]
-    fn unpacked_size() -> usize {
-        1
-    }
-
-    #[inline(always)]
-    fn packed_size() -> usize {
-        32
-    }
-}
-
-impl StorageSizeU64 of StorageSize<u64> {
-    #[inline(always)]
-    fn unpacked_size() -> usize {
-        1
-    }
-
-    #[inline(always)]
-    fn packed_size() -> usize {
-        64
-    }
-}
-
-impl StorageSizeU128 of StorageSize<u128> {
-    #[inline(always)]
-    fn unpacked_size() -> usize {
-        1
-    }
-
-    #[inline(always)]
-    fn packed_size() -> usize {
-        128
-    }
-}
-
-impl StorageSizeU256 of StorageSize<u256> {
-    #[inline(always)]
-    fn unpacked_size() -> usize {
-        2
-    }
-
-    #[inline(always)]
-    fn packed_size() -> usize {
-        256
-    }
-}
-
-impl StorageSizeContractAddress of StorageSize<starknet::ContractAddress> {
-    #[inline(always)]
-    fn unpacked_size() -> usize {
-        1
-    }
-
-    #[inline(always)]
-    fn packed_size() -> usize {
-        256
-    }
-}
-
-impl StorageSizeClassHash of StorageSize<starknet::ClassHash> {
-    #[inline(always)]
-    fn unpacked_size() -> usize {
-        1
-    }
-
-    #[inline(always)]
-    fn packed_size() -> usize {
-        256
-    }
-}
diff --git a/crates/dojo-core/src/executor_test.cairo b/crates/dojo-core/src/executor_test.cairo
index 395ca322fb..f59fc68270 100644
--- a/crates/dojo-core/src/executor_test.cairo
+++ b/crates/dojo-core/src/executor_test.cairo
@@ -10,7 +10,7 @@ use starknet::class_hash::Felt252TryIntoClassHash;
 use dojo::executor::{executor, IExecutorDispatcher, IExecutorDispatcherTrait};
 use dojo::world::{Context, IWorldDispatcher};
 
-#[derive(Component, Copy, Drop, Serde)]
+#[derive(Component, Copy, Drop, Serde, SerdeLen)]
 struct Foo {
     #[key]
     id: felt252,
diff --git a/crates/dojo-core/src/lib.cairo b/crates/dojo-core/src/lib.cairo
index 9a42520009..84541ee928 100644
--- a/crates/dojo-core/src/lib.cairo
+++ b/crates/dojo-core/src/lib.cairo
@@ -1,14 +1,12 @@
 mod database;
-use database::storage::StorageSize;
 #[cfg(test)]
 mod database_test;
 mod executor;
 #[cfg(test)]
 mod executor_test;
-mod component;
-mod packing;
-#[cfg(test)]
-mod packing_test;
+mod serde;
+use serde::SerdeLen;
+mod traits;
 mod world;
 #[cfg(test)]
 mod world_test;
diff --git a/crates/dojo-core/src/packing.cairo b/crates/dojo-core/src/packing.cairo
deleted file mode 100644
index e96304bd38..0000000000
--- a/crates/dojo-core/src/packing.cairo
+++ /dev/null
@@ -1,145 +0,0 @@
-use starknet::{ClassHash, ContractAddress};
-use array::{ArrayTrait, SpanTrait};
-use traits::{Into, TryInto};
-use integer::{U256BitAnd, U256BitOr, U256BitXor, upcast, downcast, BoundedInt};
-use option::OptionTrait;
-
-#[derive(Copy, Drop)]
-struct LayoutItem {
-    value: felt252,
-    size: u8
-}
-
-fn pack(ref unpacked: Array<LayoutItem>) -> Span<felt252> {
-    let mut packed: Array<felt252> = ArrayTrait::new();
-    let mut packing: felt252 = 0x0;
-    let mut offset: u8 = 0x0;
-    loop {
-        match unpacked.pop_front() {
-            Option::Some(s) => {
-                pack_inner(@s.value, s.size, ref packing, ref offset, ref packed);
-            },
-            Option::None(_) => {
-                break packed.span();
-            }
-        };
-    }
-}
-
-fn unpack(ref packed: Span<felt252>, ref layout: Span<u8>) -> Option<Span<felt252>> {
-    let mut unpacked: Array<felt252> = ArrayTrait::new();
-    let mut unpacking: felt252 = 0x0;
-    let mut offset: u8 = 251;
-    loop {
-        match layout.pop_front() {
-            Option::Some(s) => {
-                match unpack_inner(*s, ref packed, ref unpacking, ref offset) {
-                    Option::Some(u) => {
-                        unpacked.append(u);
-                    },
-                    Option::None(_) => {
-                        break Option::None(());
-                    }
-                }
-            },
-            Option::None(_) => {
-                break Option::Some(unpacked.span());
-            }
-        };
-    }
-}
-
-/// Pack the proposal fields into a single felt252.
-fn pack_inner(
-    self: @felt252,
-    size: u8,
-    ref packing: felt252,
-    ref packing_offset: u8,
-    ref packed: Array<felt252>
-) {
-    // Easier to work on u256 rather than felt252.
-    let self_256: u256 = (*self).into();
-
-    // Cannot use all 252 bits because some bit arrangements (eg. 11111...11111) are not valid felt252 values. 
-    // Thus only 251 bits are used.                               ^-252 times-^
-    // One could optimize by some conditional alligment mechanism, but it would be an at most 1/252 space-wise improvement.
-    let remaining_bits: u8 = (251 - packing_offset).into();
-
-    let mut packing_256: u256 = packing.into();
-
-    if remaining_bits < size {
-        let first_part = self_256 & (shl(1, remaining_bits) - 1);
-        let second_part = shr(self_256, remaining_bits);
-
-        // Pack the first part into the current felt
-        packing_256 = packing_256 | shl(first_part, packing_offset);
-        packed.append(packing_256.try_into().unwrap());
-
-        // Start a new felt and pack the second part into it
-        packing = second_part.try_into().unwrap();
-        packing_offset = size - remaining_bits;
-    } else {
-        // Pack the data into the current felt
-        packing_256 = packing_256 | shl(self_256, packing_offset);
-        packing = packing_256.try_into().unwrap();
-        packing_offset = packing_offset + size;
-    }
-}
-
-fn unpack_inner(
-    size: u8, ref packed: Span<felt252>, ref unpacking: felt252, ref unpacking_offset: u8
-) -> Option<felt252> {
-    let remaining_bits: u8 = (251 - unpacking_offset).into();
-
-    let mut unpacking_256: u256 = unpacking.into();
-
-    if remaining_bits < size {
-        match packed.pop_front() {
-            Option::Some(val) => {
-                let val_256: u256 = (*val).into();
-
-                // Get the first part
-                let first_part = shr(unpacking_256, unpacking_offset);
-                // Size of the remaining part
-                let second_size = size - remaining_bits;
-                let second_part = val_256 & (shl(1, second_size) - 1);
-                // Move the second part so it fits alongside the first part
-                let result = first_part | shl(second_part, remaining_bits);
-
-                unpacking = *val;
-                unpacking_offset = second_size;
-                return result.try_into();
-            },
-            Option::None(()) => {
-                return Option::None(());
-            },
-        }
-    } else {
-        let result = (shl(1, size) - 1) & shr(unpacking_256, unpacking_offset);
-        unpacking_offset = unpacking_offset + size;
-        return result.try_into();
-    }
-}
-
-fn fpow(x: u256, n: u8) -> u256 {
-    let y = x;
-    if n == 0 {
-        return 1;
-    }
-    if n == 1 {
-        return x;
-    }
-    let double = fpow(y * x, n / 2);
-    if (n % 2) == 1 {
-        return x * double;
-    }
-    return double;
-}
-
-fn shl(x: u256, n: u8) -> u256 {
-    x * fpow(2, n)
-}
-
-fn shr(x: u256, n: u8) -> u256 {
-    x / fpow(2, n)
-}
\ No newline at end of file
diff --git a/crates/dojo-core/src/packing_test.cairo b/crates/dojo-core/src/packing_test.cairo
deleted file mode 100644
index 2d4583acb7..0000000000
--- a/crates/dojo-core/src/packing_test.cairo
+++ /dev/null
@@ -1,25 +0,0 @@
-use array::{ArrayTrait, SpanTrait};
-use starknet::{ClassHash, ContractAddress, Felt252TryIntoContractAddress, Felt252TryIntoClassHash};
-use dojo::packing::{shl, shr, fpow};
-use integer::U256BitAnd;
-use option::OptionTrait;
-use debug::PrintTrait;
-use traits::{Into, TryInto};
-
-#[test]
-#[available_gas(9000000)]
-fn test_bit_fpow() {
-    assert(fpow(2, 250) == 1809251394333065553493296640760748560207343510400633813116524750123642650624_u256, '')
-}
-
-#[test]
-#[available_gas(9000000)]
-fn test_bit_shift() {
-    assert(1 == shl(1, 0), 'left == right');
-    assert(1 == shr(1, 0), 'left == right');
-
-    assert(16 == shl(1, 4), 'left == right');
-    assert(1 == shr(16, 4), 'left == right');
-
-    assert(shr(shl(1, 251), 251) == 1, 'left == right')
-}
diff --git a/crates/dojo-core/src/serde.cairo b/crates/dojo-core/src/serde.cairo
new file mode 100644
index 0000000000..6dd1ce0ec3
--- /dev/null
+++ b/crates/dojo-core/src/serde.cairo
@@ -0,0 +1,74 @@
+trait SerdeLen<T> {
+    fn len() -> usize;
+}
+
+impl SerdeLenFelt252 of SerdeLen<felt252> {
+    #[inline(always)]
+    fn len() -> usize {
+        1
+    }
+}
+
+impl SerdeLenBool of SerdeLen<bool> {
+    #[inline(always)]
+    fn len() -> usize {
+        1
+    }
+}
+
+impl SerdeLenU8 of SerdeLen<u8> {
+    #[inline(always)]
+    fn len() -> usize {
+        1
+    }
+}
+
+impl SerdeLenU16 of SerdeLen<u16> {
+    #[inline(always)]
+    fn len() -> usize {
+        1
+    }
+}
+
+impl SerdeLenU32 of SerdeLen<u32> {
+    #[inline(always)]
+    fn len() -> usize {
+        1
+    }
+}
+
+impl SerdeLenU64 of SerdeLen<u64> {
+    #[inline(always)]
+    fn len() -> usize {
+        1
+    }
+}
+
+impl SerdeLenU128 of SerdeLen<u128> {
+    #[inline(always)]
+    fn len() -> usize {
+        1
+    }
+}
+
+impl SerdeLenU256 of SerdeLen<u256> {
+    #[inline(always)]
+    fn len() -> usize {
+        2
+    }
+}
+
+impl SerdeLenContractAddress of SerdeLen<starknet::ContractAddress> {
+    #[inline(always)]
+    fn len() -> usize {
+        1
+    }
+}
+
+impl SerdeLenClassHash of SerdeLen<starknet::ClassHash> {
+    #[inline(always)]
+    fn len() -> usize {
+        1
+    }
+}
+
diff --git a/crates/dojo-core/src/component.cairo b/crates/dojo-core/src/traits.cairo
similarity index 100%
rename from crates/dojo-core/src/component.cairo
rename to crates/dojo-core/src/traits.cairo
diff --git a/crates/dojo-core/src/world.cairo b/crates/dojo-core/src/world.cairo
index 88592c514a..fea75d96a4 100644
--- a/crates/dojo-core/src/world.cairo
+++ b/crates/dojo-core/src/world.cairo
@@ -58,7 +58,7 @@ mod world {
 
     use dojo::database;
     use dojo::executor::{IExecutorDispatcher, IExecutorDispatcherTrait};
-    use dojo::component::{INamedLibraryDispatcher, INamedDispatcherTrait, };
+    use dojo::traits::{INamedLibraryDispatcher, INamedDispatcherTrait, };
     use dojo::world::{IWorldDispatcher, IWorld};
 
     use super::Context;
diff --git a/crates/dojo-core/src/world_factory_test.cairo b/crates/dojo-core/src/world_factory_test.cairo
index 3c7bdf92f5..5ff581b9df 100644
--- a/crates/dojo-core/src/world_factory_test.cairo
+++ b/crates/dojo-core/src/world_factory_test.cairo
@@ -16,7 +16,7 @@ use dojo::world_factory::{IWorldFactoryDispatcher, IWorldFactoryDispatcherTrait,
 use dojo::world::{IWorldDispatcher, IWorldDispatcherTrait, world};
 
 
-#[derive(Component, Copy, Drop, Serde)]
+#[derive(Component, Copy, Drop, Serde, SerdeLen)]
 struct Foo {
     #[key]
     id: felt252,
diff --git a/crates/dojo-core/src/world_test.cairo b/crates/dojo-core/src/world_test.cairo
index 1b6f3e160f..25862edf7a 100644
--- a/crates/dojo-core/src/world_test.cairo
+++ b/crates/dojo-core/src/world_test.cairo
@@ -16,7 +16,7 @@ use dojo::world::{IWorldDispatcher, IWorldDispatcherTrait, library_call, world};
 
 // Components and Systems
 
-#[derive(Component, Copy, Drop, Serde)]
+#[derive(Component, Copy, Drop, Serde, SerdeLen)]
 struct Foo {
     #[key]
     caller: ContractAddress,
@@ -24,7 +24,7 @@ struct Foo {
     b: u128,
 }
 
-#[derive(Component, Copy, Drop, Serde)]
+#[derive(Component, Copy, Drop, Serde, SerdeLen)]
 struct Fizz {
     #[key]
     caller: ContractAddress,
@@ -71,7 +71,7 @@ fn test_system() {
     let mut keys = ArrayTrait::new();
     keys.append(0);
 
-    let stored = world.entity('Foo', keys.span(), 0, dojo::StorageSize::<Foo>::unpacked_size());
+    let stored = world.entity('Foo', keys.span(), 0, dojo::SerdeLen::<Foo>::len());
     assert(*stored.snapshot.at(0) == 1337, 'data not stored');
 }
 
@@ -121,7 +121,7 @@ fn test_set_entity_admin() {
     data.append(420);
     data.append(1337);
     world.execute('bar', data);
-    let foo = world.entity('Foo', keys.span(), 0, dojo::StorageSize::<Foo>::unpacked_size());
+    let foo = world.entity('Foo', keys.span(), 0, dojo::SerdeLen::<Foo>::len());
     assert(*foo[0] == 420, 'data not stored');
     assert(*foo[1] == 1337, 'data not stored');
 }
@@ -407,8 +407,8 @@ fn test_execute_multiple_worlds() {
     world.execute('bar', data);
     another_world.execute('bar', another_data);
 
-    let stored = world.entity('Foo', keys.span(), 0, dojo::StorageSize::<Foo>::unpacked_size());
-    let another_stored = another_world.entity('Foo', keys.span(), 0, dojo::StorageSize::<Foo>::unpacked_size());
+    let stored = world.entity('Foo', keys.span(), 0, dojo::SerdeLen::<Foo>::len());
+    let another_stored = another_world.entity('Foo', keys.span(), 0, dojo::SerdeLen::<Foo>::len());
     assert(*stored.snapshot.at(0) == 1337, 'data not stored');
     assert(*another_stored.snapshot.at(0) == 7331, 'data not stored');
 }
diff --git a/crates/dojo-defi/src/market/components.cairo b/crates/dojo-defi/src/market/components.cairo
index f0fd6c05d5..0b9cbb7fd6 100644
--- a/crates/dojo-defi/src/market/components.cairo
+++ b/crates/dojo-defi/src/market/components.cairo
@@ -1,12 +1,14 @@
 use starknet::ContractAddress;
-use dojo::StorageSize;
+
+use dojo::serde::SerdeLen;
+
 
 // Cubit fixed point math library
 use cubit::f128::types::fixed::Fixed;
 
 const SCALING_FACTOR: u128 = 10000;
 
-impl StorageSizeFixed of StorageSize<Fixed> {
+impl SerdeLenFixed of SerdeLen<Fixed> {
     #[inline(always)]
     fn unpacked_size() -> usize {
         1
@@ -18,14 +20,14 @@ impl StorageSizeFixed of StorageSize<Fixed> {
     }
 }
 
-#[derive(Component, Copy, Drop, Serde)]
+#[derive(Component, Copy, Drop, Serde, SerdeLen)]
 struct Cash {
     #[key]
     player: ContractAddress,
     amount: u128,
 }
 
-#[derive(Component, Copy, Drop, Serde)]
+#[derive(Component, Copy, Drop, Serde, SerdeLen)]
 struct Item {
     #[key]
     player: ContractAddress,
@@ -34,7 +36,7 @@ struct Item {
     quantity: u128,
 }
 
-#[derive(Component, Copy, Drop, Serde)]
+#[derive(Component, Copy, Drop, Serde, SerdeLen)]
 struct Liquidity {
     #[key]
     player: ContractAddress,
@@ -43,7 +45,7 @@ struct Liquidity {
     shares: Fixed,
 }
 
-#[derive(Component, Copy, Drop, Serde)]
+#[derive(Component, Copy, Drop, Serde, SerdeLen)]
 struct Market {
     #[key]
     item_id: u32,
diff --git a/crates/dojo-erc/src/erc1155/components.cairo b/crates/dojo-erc/src/erc1155/components.cairo
index 0d5d73222a..9f0b7ecd18 100644
--- a/crates/dojo-erc/src/erc1155/components.cairo
+++ b/crates/dojo-erc/src/erc1155/components.cairo
@@ -12,7 +12,7 @@ use dojo_erc::erc_common::components::{operator_approval, OperatorApproval, Oper
 // Uri TODO: use BaseURI from erc_common
 //
 
-#[derive(Component, Copy, Drop, Serde)]
+#[derive(Component, Copy, Drop, Serde, SerdeLen)]
 struct Uri {
     #[key]
     token: ContractAddress,
@@ -23,7 +23,7 @@ struct Uri {
 // ERC1155Balance
 //
 
-#[derive(Component, Copy, Drop, Serde)]
+#[derive(Component, Copy, Drop, Serde, SerdeLen)]
 struct ERC1155Balance {
     #[key]
     token: ContractAddress,
diff --git a/crates/dojo-erc/src/erc20/components.cairo b/crates/dojo-erc/src/erc20/components.cairo
index 4266db3562..0a0b52ce51 100644
--- a/crates/dojo-erc/src/erc20/components.cairo
+++ b/crates/dojo-erc/src/erc20/components.cairo
@@ -1,6 +1,6 @@
 use starknet::ContractAddress;
 
-#[derive(Component, Copy, Drop, Serde)]
+#[derive(Component, Copy, Drop, Serde, SerdeLen)]
 struct Allowance {
     #[key]
     token: ContractAddress,
@@ -11,7 +11,7 @@ struct Allowance {
     amount: felt252,
 }
 
-#[derive(Component, Copy, Drop, Serde)]
+#[derive(Component, Copy, Drop, Serde, SerdeLen)]
 struct Balance {
     #[key]
     token: ContractAddress,
@@ -20,7 +20,7 @@ struct Balance {
     amount: felt252,
 }
 
-#[derive(Component, Copy, Drop, Serde)]
+#[derive(Component, Copy, Drop, Serde, SerdeLen)]
 struct Supply {
     #[key]
     token: ContractAddress,
diff --git a/crates/dojo-erc/src/erc721/components.cairo b/crates/dojo-erc/src/erc721/components.cairo
index 25d011fbd5..bb4284ceb0 100644
--- a/crates/dojo-erc/src/erc721/components.cairo
+++ b/crates/dojo-erc/src/erc721/components.cairo
@@ -14,7 +14,7 @@ use dojo_erc::erc_common::components::{
 // ERC721Owner
 //
 
-#[derive(Component, Copy, Drop, Serde)]
+#[derive(Component, Copy, Drop, Serde, SerdeLen)]
 struct ERC721Owner {
     #[key]
     token: ContractAddress,
@@ -56,7 +56,7 @@ impl ERC721OwnerImpl of ERC721OwnerTrait {
 // ERC721Balance
 //
 
-#[derive(Component, Copy, Drop, Serde)]
+#[derive(Component, Copy, Drop, Serde, SerdeLen)]
 struct ERC721Balance {
     #[key]
     token: ContractAddress,
@@ -133,7 +133,7 @@ impl ERC721BalanceImpl of ERC721BalanceTrait {
 // ERC721TokenApproval
 //
 
-#[derive(Component, Copy, Drop, Serde)]
+#[derive(Component, Copy, Drop, Serde, SerdeLen)]
 struct ERC721TokenApproval {
     #[key]
     token: ContractAddress,
diff --git a/crates/dojo-erc/src/erc_common/components/base_uri_component.cairo b/crates/dojo-erc/src/erc_common/components/base_uri_component.cairo
index 7c6a5fa876..39c0daafe8 100644
--- a/crates/dojo-erc/src/erc_common/components/base_uri_component.cairo
+++ b/crates/dojo-erc/src/erc_common/components/base_uri_component.cairo
@@ -1,7 +1,7 @@
 use starknet::ContractAddress;
 use dojo::world::{IWorldDispatcher, IWorldDispatcherTrait};
 
-#[derive(Component, Copy, Drop, Serde)]
+#[derive(Component, Copy, Drop, Serde, SerdeLen)]
 struct BaseUri {
     #[key]
     token: ContractAddress,
diff --git a/crates/dojo-erc/src/erc_common/components/operator_approval_component.cairo b/crates/dojo-erc/src/erc_common/components/operator_approval_component.cairo
index b8dd10f302..db792bbfb3 100644
--- a/crates/dojo-erc/src/erc_common/components/operator_approval_component.cairo
+++ b/crates/dojo-erc/src/erc_common/components/operator_approval_component.cairo
@@ -1,7 +1,7 @@
 use starknet::ContractAddress;
 use dojo::world::{IWorldDispatcher, IWorldDispatcherTrait};
 
-#[derive(Component, Copy, Drop, Serde)]
+#[derive(Component, Copy, Drop, Serde, SerdeLen)]
 struct OperatorApproval {
     #[key]
     token: ContractAddress,
diff --git a/crates/dojo-lang/src/component.rs b/crates/dojo-lang/src/component.rs
index 79a6a092c0..4328edbbdb 100644
--- a/crates/dojo-lang/src/component.rs
+++ b/crates/dojo-lang/src/component.rs
@@ -101,7 +101,7 @@ pub fn handle_component_struct(
                 $members$
             }
 
-            impl $type_name$Component of dojo::component::Component<$type_name$> {
+            impl $type_name$Component of dojo::traits::Component<$type_name$> {
                 #[inline(always)]
                 fn name(self: @$type_name$) -> felt252 {
                     '$type_name$'
@@ -122,18 +122,6 @@ pub fn handle_component_struct(
                 }
             }
 
-            impl $type_name$StorageSize of dojo::StorageSize<$type_name$> {
-                #[inline(always)]
-                fn unpacked_size() -> usize {
-                    $unpacked_size$
-                }
-
-                #[inline(always)]
-                fn packed_size() -> usize {
-                    $packed_size$
-                }
-            }
-
             #[cfg(test)]
             impl $type_name$PrintImpl of debug::PrintTrait<$type_name$> {
                 fn print(self: $type_name$) {
@@ -160,7 +148,7 @@ pub fn handle_component_struct(
 
                 #[external(v0)]
                 fn size(self: @ContractState) -> usize {
-                    dojo::StorageSize::<$type_name$>::unpacked_size()
+                    dojo::SerdeLen::<$type_name$>::len()
                 }
 
                 #[external(v0)]
@@ -193,46 +181,6 @@ pub fn handle_component_struct(
                 ("serialized_values".to_string(), RewriteNode::new_modified(serialized_values)),
                 ("schema".to_string(), RewriteNode::new_modified(schema)),
                 ("print".to_string(), RewriteNode::Text(prints.join("\n"))),
-                (
-                    "unpacked_size".to_string(),
-                    RewriteNode::Text(
-                        struct_ast
-                            .members(db)
-                            .elements(db)
-                            .iter()
-                            .filter_map(|member| {
-                                if member.has_attr(db, "key") {
-                                    return None;
-                                }
-
-                                Some(format!(
-                                    "dojo::StorageSize::<{}>::unpacked_size()",
-                                    member.type_clause(db).ty(db).as_syntax_node().get_text(db),
-                                ))
-                            })
-                            .join(" + "),
-                    ),
-                ),
-                (
-                    "packed_size".to_string(),
-                    RewriteNode::Text(
-                        struct_ast
-                            .members(db)
-                            .elements(db)
-                            .iter()
-                            .filter_map(|member| {
-                                if member.has_attr(db, "key") {
-                                    return None;
-                                }
-
-                                Some(format!(
-                                    "dojo::StorageSize::<{}>::packed_size()",
-                                    member.type_clause(db).ty(db).as_syntax_node().get_text(db),
-                                ))
-                            })
-                            .join(" + "),
-                    ),
-                ),
             ]),
         ),
         diagnostics,
diff --git a/crates/dojo-lang/src/inline_macros/get.rs b/crates/dojo-lang/src/inline_macros/get.rs
index b593352b48..445f14a012 100644
--- a/crates/dojo-lang/src/inline_macros/get.rs
+++ b/crates/dojo-lang/src/inline_macros/get.rs
@@ -86,7 +86,7 @@ impl InlineMacroExprPlugin for GetMacro {
 
             builder.add_str(&format!(
                 "\n            let __{component}_values__ = {}.entity('{component}', \
-                 __get_macro_keys__, 0_u8, dojo::StorageSize::<{component}>::unpacked_size());
+                 __get_macro_keys__, 0_u8, dojo::SerdeLen::<{component}>::len());
                  let mut __{component}_component__ = array::ArrayTrait::new();
                  array::serialize_array_helper(__get_macro_keys__, ref __{component}_component__);
                  array::serialize_array_helper(__{component}_values__, ref \
diff --git a/crates/dojo-lang/src/inline_macros/set.rs b/crates/dojo-lang/src/inline_macros/set.rs
index 08d476d4b5..7a58c7b3b3 100644
--- a/crates/dojo-lang/src/inline_macros/set.rs
+++ b/crates/dojo-lang/src/inline_macros/set.rs
@@ -77,9 +77,9 @@ impl InlineMacroExprPlugin for SetMacro {
         for entity in bundle {
             builder.add_str(&format!(
                 "\n            let __set_macro_value__ = {};
-                {}.set_entity(dojo::component::Component::name(@__set_macro_value__), \
-                 dojo::component::Component::keys(@__set_macro_value__), 0_u8, \
-                 dojo::component::Component::values(@__set_macro_value__));",
+                {}.set_entity(dojo::traits::Component::name(@__set_macro_value__), \
+                 dojo::traits::Component::keys(@__set_macro_value__), 0_u8, \
+                 dojo::traits::Component::values(@__set_macro_value__));",
                 entity,
                 world.as_syntax_node().get_text(db),
             ));
diff --git a/crates/dojo-lang/src/lib.rs b/crates/dojo-lang/src/lib.rs
index 1e2f7ef81c..7ac2ee7600 100644
--- a/crates/dojo-lang/src/lib.rs
+++ b/crates/dojo-lang/src/lib.rs
@@ -8,5 +8,6 @@ pub mod component;
 pub mod inline_macros;
 mod manifest;
 pub mod plugin;
+mod serde;
 pub mod system;
 pub(crate) mod version;
diff --git a/crates/dojo-lang/src/plugin.rs b/crates/dojo-lang/src/plugin.rs
index b779561d42..85b0cedca8 100644
--- a/crates/dojo-lang/src/plugin.rs
+++ b/crates/dojo-lang/src/plugin.rs
@@ -25,6 +25,7 @@ use crate::component::handle_component_struct;
 use crate::inline_macros::emit::EmitMacro;
 use crate::inline_macros::get::GetMacro;
 use crate::inline_macros::set::SetMacro;
+use crate::serde::handle_serde_len_struct;
 use crate::system::System;
 
 const SYSTEM_ATTR: &str = "system";
@@ -158,6 +159,9 @@ impl MacroPlugin for DojoPlugin {
                                 rewrite_nodes.push(component_rewrite_nodes);
                                 diagnostics.extend(component_diagnostics);
                             }
+                            "SerdeLen" => {
+                                rewrite_nodes.push(handle_serde_len_struct(db, struct_ast.clone()));
+                            }
                             _ => continue,
                         }
                     }
diff --git a/crates/dojo-lang/src/plugin_test_data/component b/crates/dojo-lang/src/plugin_test_data/component
index 2f7f610300..0a04308700 100644
--- a/crates/dojo-lang/src/plugin_test_data/component
+++ b/crates/dojo-lang/src/plugin_test_data/component
@@ -6,7 +6,7 @@ test_expand_plugin
 //! > cairo_code
 use serde::Serde;
 
-#[derive(Component, Copy, Drop, Serde)]
+#[derive(Component, Copy, Drop, Serde, SerdeLen)]
 struct Position {
     #[key]
     id: felt252,
@@ -38,9 +38,16 @@ struct Roles {
     role_ids: Array<u8>
 }
 
+impl RolesSerdeLen of dojo::SerdeLen<Roles> {
+    #[inline(always)]
+    fn len() -> usize {
+        5
+    }
+}
+
 use starknet::ContractAddress;
 
-#[derive(Component, Copy, Drop, Serde)]
+#[derive(Component, Copy, Drop, Serde, SerdeLen)]
 struct Player {
     #[key]
     game: felt252,
@@ -60,7 +67,7 @@ struct Position {
     y: felt252
 }
 
-impl PositionComponent of dojo::component::Component<Position> {
+impl PositionComponent of dojo::traits::Component<Position> {
     #[inline(always)]
     fn name(self: @Position) -> felt252 {
         'Position'
@@ -84,19 +91,6 @@ impl PositionComponent of dojo::component::Component<Position> {
     }
 }
 
-impl PositionStorageSize of dojo::StorageSize<Position> {
-    #[inline(always)]
-    fn unpacked_size() -> usize {
-        dojo::StorageSize::<felt252>::unpacked_size()
-            + dojo::StorageSize::<felt252>::unpacked_size()
-    }
-
-    #[inline(always)]
-    fn packed_size() -> usize {
-        dojo::StorageSize::<felt252>::packed_size() + dojo::StorageSize::<felt252>::packed_size()
-    }
-}
-
 #[cfg(test)]
 impl PositionPrintImpl of debug::PrintTrait<Position> {
     fn print(self: Position) {
@@ -128,7 +122,7 @@ mod position {
 
     #[external(v0)]
     fn size(self: @ContractState) -> usize {
-        dojo::StorageSize::<Position>::unpacked_size()
+        dojo::SerdeLen::<Position>::len()
     }
 
     #[external(v0)]
@@ -141,6 +135,13 @@ mod position {
     }
 }
 
+impl SerdeLenPosition of dojo::SerdeLen<Position> {
+    #[inline(always)]
+    fn len() -> usize {
+        dojo::SerdeLen::<felt252>::len() + dojo::SerdeLen::<felt252>::len()
+    }
+}
+
 
 
 trait PositionTrait {
@@ -166,7 +167,7 @@ struct Roles {
     role_ids: Array<u8>
 }
 
-impl RolesComponent of dojo::component::Component<Roles> {
+impl RolesComponent of dojo::traits::Component<Roles> {
     #[inline(always)]
     fn name(self: @Roles) -> felt252 {
         'Roles'
@@ -187,18 +188,6 @@ impl RolesComponent of dojo::component::Component<Roles> {
     }
 }
 
-impl RolesStorageSize of dojo::StorageSize<Roles> {
-    #[inline(always)]
-    fn unpacked_size() -> usize {
-        dojo::StorageSize::<Array<u8>>::unpacked_size()
-    }
-
-    #[inline(always)]
-    fn packed_size() -> usize {
-        dojo::StorageSize::<Array<u8>>::packed_size()
-    }
-}
-
 #[cfg(test)]
 impl RolesPrintImpl of debug::PrintTrait<Roles> {
     fn print(self: Roles) {
@@ -226,7 +215,7 @@ mod roles {
 
     #[external(v0)]
     fn size(self: @ContractState) -> usize {
-        dojo::StorageSize::<Roles>::unpacked_size()
+        dojo::SerdeLen::<Roles>::len()
     }
 
     #[external(v0)]
@@ -239,6 +228,14 @@ mod roles {
 
 
 
+impl RolesSerdeLen of dojo::SerdeLen<Roles> {
+    #[inline(always)]
+    fn len() -> usize {
+        5
+    }
+}
+
+
 use starknet::ContractAddress;
 
 struct Player {
@@ -249,7 +246,7 @@ struct Player {
     name: felt252,
 }
 
-impl PlayerComponent of dojo::component::Component<Player> {
+impl PlayerComponent of dojo::traits::Component<Player> {
     #[inline(always)]
     fn name(self: @Player) -> felt252 {
         'Player'
@@ -272,18 +269,6 @@ impl PlayerComponent of dojo::component::Component<Player> {
     }
 }
 
-impl PlayerStorageSize of dojo::StorageSize<Player> {
-    #[inline(always)]
-    fn unpacked_size() -> usize {
-        dojo::StorageSize::<felt252>::unpacked_size()
-    }
-
-    #[inline(always)]
-    fn packed_size() -> usize {
-        dojo::StorageSize::<felt252>::packed_size()
-    }
-}
-
 #[cfg(test)]
 impl PlayerPrintImpl of debug::PrintTrait<Player> {
     fn print(self: Player) {
@@ -315,7 +300,7 @@ mod player {
 
     #[external(v0)]
     fn size(self: @ContractState) -> usize {
-        dojo::StorageSize::<Player>::unpacked_size()
+        dojo::SerdeLen::<Player>::len()
     }
 
     #[external(v0)]
@@ -328,6 +313,13 @@ mod player {
     }
 }
 
+impl SerdeLenPlayer of dojo::SerdeLen<Player> {
+    #[inline(always)]
+    fn len() -> usize {
+        dojo::SerdeLen::<felt252>::len()
+    }
+}
+
 //! > expected_diagnostics
 error: Component must define atleast one #[key] attribute
  --> dummy_file.cairo:31:8
diff --git a/crates/dojo-lang/src/serde.rs b/crates/dojo-lang/src/serde.rs
new file mode 100644
index 0000000000..6cb1eb14d7
--- /dev/null
+++ b/crates/dojo-lang/src/serde.rs
@@ -0,0 +1,50 @@
+use cairo_lang_defs::patcher::RewriteNode;
+use cairo_lang_syntax::node::ast::ItemStruct;
+use cairo_lang_syntax::node::db::SyntaxGroup;
+use cairo_lang_syntax::node::helpers::QueryAttrs;
+use cairo_lang_syntax::node::TypedSyntaxNode;
+use cairo_lang_utils::unordered_hash_map::UnorderedHashMap;
+use itertools::Itertools;
+
+/// A handler for Dojo code derives SerdeLen for a struct
+/// Parameters:
+/// * db: The semantic database.
+/// * struct_ast: The AST of the struct.
+/// Returns:
+/// * A RewriteNode containing the generated code.
+pub fn handle_serde_len_struct(db: &dyn SyntaxGroup, struct_ast: ItemStruct) -> RewriteNode {
+    RewriteNode::interpolate_patched(
+        "
+        impl SerdeLen$name$ of dojo::SerdeLen<$type$> {
+            #[inline(always)]
+            fn len() -> usize {
+                $len$
+            }
+        }
+        ",
+        UnorderedHashMap::from([
+            ("name".to_string(), RewriteNode::new_trimmed(struct_ast.name(db).as_syntax_node())),
+            ("type".to_string(), RewriteNode::new_trimmed(struct_ast.name(db).as_syntax_node())),
+            (
+                "len".to_string(),
+                RewriteNode::Text(
+                    struct_ast
+                        .members(db)
+                        .elements(db)
+                        .iter()
+                        .filter_map(|member| {
+                            if member.has_attr(db, "key") {
+                                return None;
+                            }
+
+                            Some(format!(
+                                "dojo::SerdeLen::<{}>::len()",
+                                member.type_clause(db).ty(db).as_syntax_node().get_text(db),
+                            ))
+                        })
+                        .join(" + "),
+                ),
+            ),
+        ]),
+    )
+}
diff --git a/examples/ecs/src/components.cairo b/examples/ecs/src/components.cairo
index 398db8b7c1..f392d60765 100644
--- a/examples/ecs/src/components.cairo
+++ b/examples/ecs/src/components.cairo
@@ -11,16 +11,11 @@ enum Direction {
     Down: (),
 }
 
-impl DirectionStorageSizeImpl of dojo::StorageSize<Direction> {
+impl SerdeLenDirection of dojo::SerdeLen<Direction> {
     #[inline(always)]
-    fn unpacked_size() -> usize {
+    fn len() -> usize {
         1
     }
-
-    #[inline(always)]
-    fn packed_size() -> usize {
-        2
-    }
 }
 
 impl DirectionPrintImpl of PrintTrait<Direction> {
@@ -47,7 +42,7 @@ impl DirectionIntoFelt252 of Into<Direction, felt252> {
     }
 }
 
-#[derive(Component, Copy, Drop, Serde)]
+#[derive(Component, Copy, Drop, Serde, SerdeLen)]
 struct Moves {
     #[key]
     player: ContractAddress,
@@ -55,7 +50,7 @@ struct Moves {
     last_direction: Direction
 }
 
-#[derive(Component, Copy, Drop, Serde)]
+#[derive(Component, Copy, Drop, Serde, SerdeLen)]
 struct Position {
     #[key]
     player: ContractAddress,
diff --git a/examples/ecs/src/systems.cairo b/examples/ecs/src/systems.cairo
index 46fda78a45..f234d2a93f 100644
--- a/examples/ecs/src/systems.cairo
+++ b/examples/ecs/src/systems.cairo
@@ -125,11 +125,11 @@ mod tests {
         let mut keys = array::ArrayTrait::new();
         keys.append(caller.into());
 
-        let moves = world.entity('Moves', keys.span(), 0, dojo::StorageSize::<Moves>::unpacked_size());
+        let moves = world.entity('Moves', keys.span(), 0, dojo::SerdeLen::<Moves>::len());
         assert(*moves[0] == 9, 'moves is wrong');
         assert(*moves[1] == move::Direction::Right(()).into(), 'last direction is wrong');
         let new_position = world
-            .entity('Position', keys.span(), 0, dojo::StorageSize::<Position>::unpacked_size());
+            .entity('Position', keys.span(), 0, dojo::SerdeLen::<Position>::len());
         assert(*new_position[0] == 11, 'position x is wrong');
         assert(*new_position[1] == 10, 'position y is wrong');
     }