diff --git a/crates/wasm-backend-traits/Cargo.toml b/crates/wasm-backend-traits/Cargo.toml
index 8f55d4e1..55a90fad 100644
--- a/crates/wasm-backend-traits/Cargo.toml
+++ b/crates/wasm-backend-traits/Cargo.toml
@@ -14,4 +14,6 @@ wasmer-it = { package = "wasmer-interface-types-fl", version = "0.21.1" }
 wasmer-runtime = { package = "wasmer-runtime-fl", version = "=0.17.1" }
 # dynamicfunc-fat-closures allows using state inside DynamicFunc
 wasmer-core = { package = "wasmer-runtime-core-fl", version = "=0.17.1", features = ["dynamicfunc-fat-closures"] }
-wasmer-wasi = { package = "wasmer-wasi-fl", version = "0.17.1" }
\ No newline at end of file
+wasmer-wasi = { package = "wasmer-wasi-fl", version = "0.17.1" }
+
+tuple_list = "0.1.0"
\ No newline at end of file
diff --git a/crates/wasm-backend-traits/src/lib.rs b/crates/wasm-backend-traits/src/lib.rs
index d7c51dbc..331a4328 100644
--- a/crates/wasm-backend-traits/src/lib.rs
+++ b/crates/wasm-backend-traits/src/lib.rs
@@ -1,13 +1,93 @@
 //pub mod errors;
 //pub mod it_memory_traits;
+//pub mod wasm_type_list;
 
+//pub use wasm_type_list::WasmTypeList;
+use std::borrow::Cow;
+use std::fmt::Display;
 //use std::fmt::Display;
 use std::path::PathBuf;
 use thiserror::Error;
-use wasmer_core::types::FuncSig;
 use it_memory_traits::{SequentialMemoryView};
+//use wasmer_it::IValue;
 
-pub struct Value {}
+//use wasmer_core::types::FuncSig;
+use wasmer_core::error::CallResult;
+use wasmer_core::typed_func::WasmTypeList;
+use wasmer_core::types::WasmExternType;
+//use wasmer_core::typed_func::WasmTypeList;
+//use wasmer_core::types::FuncSig as Wasme;
+//pub use tuple_list::Tuple;
+
+#[derive(Debug, Clone, PartialEq)]
+pub enum WValue {
+    /// The `i32` type.
+    I32(i32),
+    /// The `i64` type.
+    I64(i64),
+    /// The `f32` type.
+    F32(f32),
+    /// The `f64` type.
+    F64(f64),
+    // /// The `v128` type.
+    //V128(u128),
+}
+
+impl From<i32> for WValue {
+    fn from(value: i32) -> Self {
+        WValue::I32(value)
+    }
+}
+
+impl From<i64> for WValue {
+    fn from(value: i64) -> Self {
+        WValue::I64(value)
+    }
+}
+
+impl From<f32> for WValue {
+    fn from(value: f32) -> Self {
+        WValue::F32(value)
+    }
+}
+
+impl From<f64> for WValue {
+    fn from(value: f64) -> Self {
+        WValue::F64(value)
+    }
+}
+
+#[derive(Debug, Clone, Copy, PartialEq, Eq, Hash)]
+pub enum WType {
+    /// The `i32` type.
+    I32,
+    /// The `i64` type.
+    I64,
+    /// The `f32` type.
+    F32,
+    /// The `f64` type.
+    F64,
+    // /// The `v128` type.
+    // V128,
+}
+
+impl WValue {
+    pub fn to_u128(&self) -> u128 {
+        match *self {
+            Self::I32(x) => x as u128,
+            Self::I64(x) => x as u128,
+            Self::F32(x) => f32::to_bits(x) as u128,
+            Self::F64(x) => f64::to_bits(x) as u128,
+            //Self::V128(x) => x,
+        }
+    }
+}
+
+impl std::fmt::Display for WType {
+    fn fmt(&self, f: &mut std::fmt::Formatter) -> std::fmt::Result {
+        write!(f, "{:?}", self)
+    }
+}
 
 #[derive(Debug, Error)]
 pub enum WasmBackendError {
@@ -31,7 +111,8 @@ pub trait WasmBackend: Clone + 'static {
     type I: Instance<Self>;
     type Wasi: WasiImplementation<Self>;
     type Namespace: Namespace<Self>;
-    type ExportContext: ExportContext<Self>;
+    type ExportContext: for<'c> ExportContext<'c, Self>;
+    type ExportedDynFunc: ExportedDynFunc<Self>;
 
     fn compile(wasm: &[u8]) -> WasmBackendResult<Self::M>;
 }
@@ -61,15 +142,17 @@ pub trait Instance<WB: WasmBackend> {
 }
 
 pub trait Exports<WB: WasmBackend> {
-    fn get<'a, T: wasmer_core::export::Exportable<'a>>(
+    fn get_func_no_args_no_rets<'a>(
         &'a self,
         name: &str,
-    ) -> wasmer_core::error::ResolveResult<T>;
+    ) -> wasmer_core::error::ResolveResult<
+        Box<dyn Fn() -> wasmer_core::error::RuntimeResult<()> + 'a>,
+    >;
 
-    fn get_func_no_args<'a, Rets: wasmer_core::typed_func::WasmTypeList + 'a>(
+    fn get_dyn_func<'a>(
         &'a self,
         name: &str,
-    ) -> wasmer_core::error::ResolveResult<Box<dyn Fn() -> wasmer_core::error::RuntimeResult<Rets> + 'a>>;
+    ) -> wasmer_core::error::ResolveResult<<WB as WasmBackend>::ExportedDynFunc>;
 }
 
 pub enum Export<M: MemoryExport, F: FunctionExport> {
@@ -125,13 +208,9 @@ pub trait Memory<WB: WasmBackend> {
 }
 
 pub trait DynamicFunc<'a, WB: WasmBackend> {
-    fn new<'c, F>(sig: std::sync::Arc<FuncSig>, func: F) -> Self
+    fn new<'c, F>(sig: FuncSig, func: F) -> Self
     where
-        F: Fn(
-                &mut <WB as WasmBackend>::ExportContext,
-                &[wasmer_core::types::Value],
-            ) -> Vec<wasmer_core::types::Value>
-            + 'static;
+        F: Fn(&mut <WB as WasmBackend>::ExportContext, &[WValue]) -> Vec<WValue> + 'static;
 }
 
 pub trait Namespace<WB: WasmBackend>: LikeNamespace<WB> {
@@ -142,14 +221,46 @@ pub trait Namespace<WB: WasmBackend>: LikeNamespace<WB> {
 
 pub trait LikeNamespace<WB: WasmBackend> {}
 
-pub trait ExportContext<WB: WasmBackend> {
+pub trait ExportContext<'c, WB: WasmBackend> {
     fn memory(&self, memory_index: u32) -> <WB as WasmBackend>::WITMemory;
 
-    unsafe fn get_export_func_by_name<'a, Args, Rets>(
-        &mut self,
+    unsafe fn get_export_func_by_name<Args, Rets>(
+        &'c mut self,
         name: &str,
-    ) -> Result<wasmer_runtime::Func<'a, Args, Rets>, wasmer_runtime::error::ResolveError>
+    ) -> Result<Box<dyn FnMut(Args) -> Result<Rets, wasmer_runtime::error::RuntimeError> + 'c>, wasmer_runtime::error::ResolveError>
     where
-        Args: wasmer_core::typed_func::WasmTypeList,
-        Rets: wasmer_core::typed_func::WasmTypeList;
+        Args: WasmTypeList,
+        Rets: WasmTypeList;
+}
+
+pub trait ExportedDynFunc<WB: WasmBackend> {
+    fn signature(&self) -> &FuncSig;
+
+    fn call(&self, args: &[WValue]) -> CallResult<Vec<WValue>>;
+}
+
+pub struct FuncSig {
+    params: Cow<'static, [WType]>,
+    returns: Cow<'static, [WType]>,
+}
+
+impl FuncSig {
+    pub fn new<Params, Returns>(params: Params, returns: Returns) -> Self
+    where
+        Params: Into<Cow<'static, [WType]>>,
+        Returns: Into<Cow<'static, [WType]>>,
+    {
+        Self {
+            params: params.into(),
+            returns: returns.into(),
+        }
+    }
+
+    pub fn params(&self) -> impl Iterator<Item = &WType> {
+        self.params.iter()
+    }
+
+    pub fn returns(&self) -> impl Iterator<Item = &WType> {
+        self.returns.iter()
+    }
 }
diff --git a/crates/wasm-backend-traits/src/wasm_type_list.rs b/crates/wasm-backend-traits/src/wasm_type_list.rs
new file mode 100644
index 00000000..b8638aa2
--- /dev/null
+++ b/crates/wasm-backend-traits/src/wasm_type_list.rs
@@ -0,0 +1,272 @@
+//use wasmer_core::types::NativeWasmType;
+use crate::WType;
+use crate::WValue;
+
+
+/// Represents a native wasm type.
+pub unsafe trait NativeWasmType: Copy + Into<WValue>
+    where
+        Self: Sized,
+{
+    /// Type for this `NativeWasmType`.
+    const TYPE: WType;
+
+    /// Convert from u64 bites to self.
+    fn from_binary(bits: u64) -> Self;
+
+    /// Convert self to u64 binary representation.
+    fn to_binary(self) -> u64;
+}
+
+unsafe impl NativeWasmType for i32 {
+    const TYPE: WType = WType::I32;
+
+    fn from_binary(bits: u64) -> Self {
+        bits as _
+    }
+
+    fn to_binary(self) -> u64 {
+        self as _
+    }
+}
+
+unsafe impl NativeWasmType for i64 {
+    const TYPE: WType = WType::I64;
+
+    fn from_binary(bits: u64) -> Self {
+        bits as _
+    }
+
+    fn to_binary(self) -> u64 {
+        self as _
+    }
+}
+
+unsafe impl NativeWasmType for f32 {
+    const TYPE: WType = WType::F32;
+
+    fn from_binary(bits: u64) -> Self {
+        f32::from_bits(bits as u32)
+    }
+
+    fn to_binary(self) -> u64 {
+        self.to_bits() as _
+    }
+}
+
+unsafe impl NativeWasmType for f64 {
+    const TYPE: WType = WType::F64;
+
+    fn from_binary(bits: u64) -> Self {
+        f64::from_bits(bits)
+    }
+
+    fn to_binary(self) -> u64 {
+        self.to_bits()
+    }
+}
+
+
+pub unsafe trait WasmExternType: Copy
+    where
+        Self: Sized,
+{
+    /// Native wasm type for this `WasmExternType`.
+    type Native: NativeWasmType;
+
+    /// Convert from given `Native` type to self.
+    fn from_native(native: Self::Native) -> Self;
+
+    /// Convert self to `Native` type.
+    fn to_native(self) -> Self::Native;
+}
+
+/// Represents a list of WebAssembly values.
+pub trait WasmTypeList {
+    /// CStruct type.
+    type CStruct;
+
+    /// Array of return values.
+    type RetArray: AsMut<[u64]>;
+
+    const NTypes: usize;
+    const Types: [WType];
+
+    /// Construct `Self` based on an array of returned values.
+    fn from_ret_array(array: Self::RetArray) -> Self;
+
+    /// Generates an empty array that will hold the returned values of
+    /// the WebAssembly function.
+    fn empty_ret_array() -> Self::RetArray;
+
+    /// Transforms C values into Rust values.
+    fn from_c_struct(c_struct: Self::CStruct) -> Self;
+
+    /// Transforms Rust values into C values.
+    fn into_c_struct(self) -> Self::CStruct;
+
+    /// Get types of the current values.
+    fn types() -> &'static [WType];
+
+    /*
+    /// This method is used to distribute the values onto a function,
+    /// e.g. `(1, 2).call(func, …)`. This form is unlikely to be used
+    /// directly in the code, see the `Func::call` implementation.
+    unsafe fn call<Rets>(
+        self,
+        f: std::ptr::NonNull<wasmer_core::vm::Func>,
+        wasm: wasmer_core::typed_func::Wasm,
+        ctx: *mut wasmer_core::vm::Ctx,
+    ) -> Result<Rets, wasmer_core::error::RuntimeError>
+        where
+            Rets: WasmTypeList;*/
+}
+
+
+macro_rules! impl_traits {
+    ( [$repr:ident] $struct_name:ident, $( $x:ident ),* ) => {
+        /// Struct for typed funcs.
+        #[repr($repr)]
+        pub struct $struct_name< $( $x ),* > ( $( <$x as WasmExternType>::Native ),* )
+        where
+            $( $x: WasmExternType ),*;
+
+        #[allow(unused_parens)]
+        impl< $( $x ),* > WasmTypeList for ( $( $x ),* )
+        where
+            $( $x: WasmExternType ),*
+        {
+            type CStruct = $struct_name<$( $x ),*>;
+
+            type RetArray = [u64; count_idents!( $( $x ),* )];
+
+            const NTypes: usize = count_idents!( $( $x ),* );
+            const Types: [WType] = [$( $x::Native::TYPE ),*];
+
+            fn from_ret_array(array: Self::RetArray) -> Self {
+                #[allow(non_snake_case)]
+                let [ $( $x ),* ] = array;
+
+                ( $( WasmExternType::from_native(NativeWasmType::from_binary($x)) ),* )
+            }
+
+            fn empty_ret_array() -> Self::RetArray {
+                [0; count_idents!( $( $x ),* )]
+            }
+
+            fn from_c_struct(c_struct: Self::CStruct) -> Self {
+                #[allow(non_snake_case)]
+                let $struct_name ( $( $x ),* ) = c_struct;
+
+                ( $( WasmExternType::from_native($x) ),* )
+            }
+
+            #[allow(unused_parens, non_snake_case)]
+            fn into_c_struct(self) -> Self::CStruct {
+                let ( $( $x ),* ) = self;
+
+                $struct_name ( $( WasmExternType::to_native($x) ),* )
+            }
+
+            fn types() -> &'static [WType] {
+                &Self::Types
+            }
+
+            /*
+            #[allow(unused_parens, non_snake_case)]
+            unsafe fn call<Rets>(
+                self,
+                f: NonNull<vm::Func>,
+                wasm: Wasm,
+                ctx: *mut vm::Ctx,
+            ) -> Result<Rets, RuntimeError>
+            where
+                Rets: WasmTypeList
+            {
+                let ( $( $x ),* ) = self;
+                let args = [ $( $x.to_native().to_binary()),* ];
+                let mut rets = Rets::empty_ret_array();
+                let mut error_out = None;
+
+                if (wasm.invoke)(
+                    wasm.trampoline,
+                    ctx,
+                    f,
+                    args.as_ptr(),
+                    rets.as_mut().as_mut_ptr(),
+                    &mut error_out,
+                    wasm.invoke_env
+                ) {
+                    Ok(Rets::from_ret_array(rets))
+                } else {
+                    Err(error_out.map_or_else(|| RuntimeError::InvokeError(InvokeError::FailedWithNoError), Into::into))
+                }
+            }*/
+        }
+    };
+}
+
+macro_rules! count_idents {
+    ( $($idents:ident),* ) => {{
+        #[allow(dead_code, non_camel_case_types)]
+        enum Idents { $($idents,)* __CountIdentsLast }
+        const COUNT: usize = Idents::__CountIdentsLast as usize;
+        COUNT
+    }};
+}
+
+macro_rules! wasm_extern_type {
+    ($type:ty => $native_type:ty) => {
+        unsafe impl WasmExternType for $type {
+            type Native = $native_type;
+
+            fn from_native(native: Self::Native) -> Self {
+                native as _
+            }
+
+            fn to_native(self) -> Self::Native {
+                self as _
+            }
+        }
+    };
+}
+
+wasm_extern_type!(i8 => i32);
+wasm_extern_type!(u8 => i32);
+wasm_extern_type!(i16 => i32);
+wasm_extern_type!(u16 => i32);
+wasm_extern_type!(i32 => i32);
+wasm_extern_type!(u32 => i32);
+wasm_extern_type!(i64 => i64);
+wasm_extern_type!(u64 => i64);
+wasm_extern_type!(f32 => f32);
+wasm_extern_type!(f64 => f64);
+
+impl_traits!([C] S0,);
+impl_traits!([transparent] S1, A);
+impl_traits!([C] S2, A, B);
+impl_traits!([C] S3, A, B, C);
+impl_traits!([C] S4, A, B, C, D);
+impl_traits!([C] S5, A, B, C, D, E);
+impl_traits!([C] S6, A, B, C, D, E, F);
+impl_traits!([C] S7, A, B, C, D, E, F, G);
+impl_traits!([C] S8, A, B, C, D, E, F, G, H);
+impl_traits!([C] S9, A, B, C, D, E, F, G, H, I);
+impl_traits!([C] S10, A, B, C, D, E, F, G, H, I, J);
+impl_traits!([C] S11, A, B, C, D, E, F, G, H, I, J, K);
+impl_traits!([C] S12, A, B, C, D, E, F, G, H, I, J, K, L);
+impl_traits!([C] S13, A, B, C, D, E, F, G, H, I, J, K, L, M);
+impl_traits!([C] S14, A, B, C, D, E, F, G, H, I, J, K, L, M, N);
+impl_traits!([C] S15, A, B, C, D, E, F, G, H, I, J, K, L, M, N, O);
+impl_traits!([C] S16, A, B, C, D, E, F, G, H, I, J, K, L, M, N, O, P);
+impl_traits!([C] S17, A, B, C, D, E, F, G, H, I, J, K, L, M, N, O, P, Q);
+impl_traits!([C] S18, A, B, C, D, E, F, G, H, I, J, K, L, M, N, O, P, Q, R);
+impl_traits!([C] S19, A, B, C, D, E, F, G, H, I, J, K, L, M, N, O, P, Q, R, S);
+impl_traits!([C] S20, A, B, C, D, E, F, G, H, I, J, K, L, M, N, O, P, Q, R, S, T);
+impl_traits!([C] S21, A, B, C, D, E, F, G, H, I, J, K, L, M, N, O, P, Q, R, S, T, U);
+impl_traits!([C] S22, A, B, C, D, E, F, G, H, I, J, K, L, M, N, O, P, Q, R, S, T, U, V);
+impl_traits!([C] S23, A, B, C, D, E, F, G, H, I, J, K, L, M, N, O, P, Q, R, S, T, U, V, W);
+impl_traits!([C] S24, A, B, C, D, E, F, G, H, I, J, K, L, M, N, O, P, Q, R, S, T, U, V, W, X);
+impl_traits!([C] S25, A, B, C, D, E, F, G, H, I, J, K, L, M, N, O, P, Q, R, S, T, U, V, W, X, Y);
+impl_traits!([C] S26, A, B, C, D, E, F, G, H, I, J, K, L, M, N, O, P, Q, R, S, T, U, V, W, X, Y, Z);
+
diff --git a/crates/wasmer-backend/src/lib.rs b/crates/wasmer-backend/src/lib.rs
index 88adc6ed..d6b7c0b6 100644
--- a/crates/wasmer-backend/src/lib.rs
+++ b/crates/wasmer-backend/src/lib.rs
@@ -1,7 +1,6 @@
+use std::marker::PhantomData;
 //use std::marker::PhantomData;
-use marine_wasm_backend_traits::{
-    DynamicFunc, Export, ExportContext, LikeNamespace, Memory, Namespace, Value, WasmBackend,
-};
+use marine_wasm_backend_traits::{DynamicFunc, Export, ExportContext, ExportedDynFunc, LikeNamespace, Memory, Namespace, WValue, WasmBackend};
 use marine_wasm_backend_traits::WasmBackendResult;
 use marine_wasm_backend_traits::WasmBackendError;
 use marine_wasm_backend_traits::Module;
@@ -11,27 +10,40 @@ use marine_wasm_backend_traits::FunctionExport;
 use marine_wasm_backend_traits::MemoryExport;
 use marine_wasm_backend_traits::Exports;
 use marine_wasm_backend_traits::WasiImplementation;
+use marine_wasm_backend_traits::FuncSig;
+use marine_wasm_backend_traits::Tuple;
+
 
 use std::path::PathBuf;
+use std::ptr::NonNull;
 use std::slice::Windows;
 use std::sync::Arc;
 use wasmer_core::backend::SigRegistry;
-use wasmer_core::error::{ResolveError, ResolveResult};
+use wasmer_core::error::{CallResult, ResolveError, ResolveResult, RuntimeError};
 use wasmer_core::fault::raw::longjmp;
-use wasmer_core::Func;
+use wasmer_core::{DynFunc, Func};
 use wasmer_core::module::ExportIndex;
-use wasmer_core::typed_func::WasmTypeList;
-//use wasmer_core::prelude::vm::Ctx;
-use wasmer_core::types::{FuncSig, LocalOrImport, WasmExternType};
+use wasmer_core::prelude::Type;
+use wasmer_core::prelude::vm::Ctx;
+use wasmer_core::typed_func::Wasm;
+use wasmer_core::types::{LocalOrImport, WasmExternType};
+use wasmer_core::types::FuncSig as WasmerFuncSig;
+use wasmer_core::typed_func::WasmTypeList as WasmerWasmTypeList;
 use wasmer_wasi::state::WasiState;
+use wasmer_it::IValue;
 
 mod memory_access;
 mod memory;
+mod type_converters;
+mod wasm_type_list;
 
 //use wasmer_it::interpreter::wasm::structures::{SequentialMemoryView, SequentialReader, SequentialWriter};
 use crate::memory::WITMemoryView;
 use crate::memory::WITMemory;
 use crate::memory_access::{WasmerSequentialReader, WasmerSequentialWriter};
+use crate::type_converters::{general_wval_to_wval, wval_to_general_wval};
+
+
 
 #[derive(Clone)]
 pub struct WasmerBackend /*<'a>*/ {
@@ -53,6 +65,7 @@ impl WasmBackend for WasmerBackend /*<'b>*/ {
     type DynamicFunc = WasmerDynamicFunc;
     type Namespace = WasmerNamespace;
     type ExportContext = WasmerExportContext<'static>;
+    type ExportedDynFunc = WasmerExportedDynFunc<'static>;
 
     fn compile(wasm: &[u8]) -> WasmBackendResult<WasmerModule> {
         wasmer_runtime::compile(wasm)
@@ -231,30 +244,31 @@ impl WasiImplementation<WasmerBackend> for WasmerWasiImplementation {
 }
 
 impl Exports<WasmerBackend> for WasmerInstance {
-    fn get<'a, T: wasmer_core::export::Exportable<'a>>(
-        &'a self,
-        name: &str,
-    ) -> wasmer_core::error::ResolveResult<T> {
-        self.instance.exports.get(name)
-    }
-
-    fn get_func_no_args<'a, Rets: WasmTypeList + 'a>(
+    fn get_func_no_args_no_rets<'a>(
         &'a self,
         name: &str,
     ) -> wasmer_core::error::ResolveResult<
-        Box<dyn Fn() -> wasmer_core::error::RuntimeResult<Rets> + 'a>,
+        Box<dyn Fn() -> wasmer_core::error::RuntimeResult<()> + 'a>,
     > {
+        self.instance.exports.get::<Func<'a>>(name).map(|func| {
+            let func: Box<dyn Fn() -> wasmer_core::error::RuntimeResult<()> + 'a> =
+                Box::new(move || -> wasmer_core::error::RuntimeResult<()> { func.call() });
+            func
+        })
+    }
+
+    fn get_dyn_func<'a>(
+        &'a self,
+        name: &str,
+    ) -> ResolveResult<<WasmerBackend as WasmBackend>::ExportedDynFunc> {
         self.instance
             .exports
-            .get::<Func<'a, (), Rets>>(name)
-            .map(|func| {
-                let func: Box<dyn Fn() -> wasmer_core::error::RuntimeResult<Rets> + 'a> =
-                    Box::new(
-                        move || -> wasmer_core::error::RuntimeResult<Rets> {
-                            func.call()
-                        },
-                    );
-                func
+            .get::<DynFunc<'_>>(name)
+            .map(|func| unsafe {
+                WasmerExportedDynFunc {
+                    sig: FuncSigConverter(func.signature()).into(),
+                    func: std::mem::transmute::<DynFunc<'_>, DynFunc<'static>>(func),
+                }
             })
     }
 }
@@ -320,16 +334,12 @@ pub struct WasmerDynamicFunc {
 }
 
 impl<'a> DynamicFunc<'a, WasmerBackend> for WasmerDynamicFunc {
-    fn new<F>(sig: Arc<FuncSig>, func: F) -> Self
+    fn new<F>(sig: FuncSig, func: F) -> Self
     where
-        F: Fn(
-                &mut WasmerExportContext<'static>,
-                &[wasmer_core::prelude::Value],
-            ) -> Vec<wasmer_core::prelude::Value>
-            + 'static,
+        F: Fn(&mut WasmerExportContext<'static>, &[WValue]) -> Vec<WValue> + 'static,
     {
         let func = wasmer_core::typed_func::DynamicFunc::new(
-            sig,
+            std::sync::Arc::new(FuncSigConverter(&sig).into()),
             move |ctx: &mut wasmer_core::vm::Ctx, args: &[wasmer_core::prelude::Value]| unsafe {
                 let mut ctx = WasmerExportContext {
                     ctx: std::mem::transmute::<
@@ -338,7 +348,11 @@ impl<'a> DynamicFunc<'a, WasmerBackend> for WasmerDynamicFunc {
                     >(ctx),
                 };
 
-                func(&mut ctx, args)
+                let args = args.iter().map(wval_to_general_wval).collect::<Vec<_>>();
+                func(&mut ctx, &args)
+                    .iter()
+                    .map(general_wval_to_wval)
+                    .collect()
             },
         );
 
@@ -374,18 +388,18 @@ pub struct WasmerExportContext<'c> {
     ctx: &'c mut wasmer_core::vm::Ctx,
 }
 
-impl<'c> ExportContext<WasmerBackend> for WasmerExportContext<'c> {
+impl<'c> ExportContext<'c, WasmerBackend> for WasmerExportContext<'static> {
     fn memory(&self, memory_index: u32) -> <WasmerBackend as WasmBackend>::WITMemory {
         WITMemory(self.ctx.memory(memory_index).clone())
     }
 
-    unsafe fn get_export_func_by_name<'a, Args, Rets>(
-        &mut self,
+    unsafe fn get_export_func_by_name<Args, Rets>(
+        &'c mut self,
         name: &str,
-    ) -> Result<Func<'a, Args, Rets>, ResolveError>
+    ) -> Result<Box<dyn FnMut(Args) -> Result<Rets, RuntimeError> + 'c>, ResolveError>
     where
-        Args: wasmer_core::typed_func::WasmTypeList,
-        Rets: wasmer_core::typed_func::WasmTypeList,
+        Args: Tuple,
+        Rets: Tuple,
     {
         let ctx = &mut self.ctx;
         let module_inner = &(*ctx.module);
@@ -417,12 +431,14 @@ impl<'c> ExportContext<WasmerBackend> for WasmerExportContext<'c> {
         let export_func_signature = &module_inner.info.signatures[export_func_signature_idx];
         let export_func_signature_ref = SigRegistry.lookup_signature_ref(export_func_signature);
 
-        if export_func_signature_ref.params() != Args::types()
-            || export_func_signature_ref.returns() != Rets::types()
+        let arg_types = <Args::CStruct as wasmer_core::typed_func::WasmTypeList>::types();
+        let ret_types = <Rets::CStruct as wasmer_core::typed_func::WasmTypeList>::types();
+        if export_func_signature_ref.params() != arg_types//Args::types()
+            || export_func_signature_ref.returns() != ret_types//Rets::types()
         {
             return Err(ResolveError::Signature {
                 expected: (*export_func_signature).clone(),
-                found: Args::types().to_vec(),
+                found: /*Helper::<Args>::types()*/ret_types.to_vec(),
             });
         }
 
@@ -443,9 +459,78 @@ impl<'c> ExportContext<WasmerBackend> for WasmerExportContext<'c> {
             }
         };
 
+
         let typed_func: Func<'_, Args, Rets, wasmer_core::typed_func::Wasm> =
             Func::from_raw_parts(func_wasm_inner, export_func_ptr, None, (*ctx) as _);
 
-        Ok(typed_func)
+        let result = Box::new(
+            move |args: Args| -> Result<Rets, RuntimeError> {
+                args.into_c_struct()
+                    .call::<Rets::CStruct>(export_func_ptr, func_wasm_inner, *ctx)
+                    .map(|rets: Rets| rets.0)
+            }
+        );
+
+        Ok(result)
+    }
+}
+
+pub struct WasmerExportedDynFunc<'a> {
+    func: DynFunc<'a>,
+    sig: FuncSig,
+}
+
+impl<'a> ExportedDynFunc<WasmerBackend> for WasmerExportedDynFunc<'a> {
+    fn signature(&self) -> &FuncSig {
+        &self.sig
+    }
+
+    fn call(&self, args: &[WValue]) -> CallResult<Vec<WValue>> {
+        use crate::type_converters::general_wval_to_wval;
+        use crate::type_converters::wval_to_general_wval;
+        self.func
+            .call(
+                &args
+                    .iter()
+                    .map(general_wval_to_wval)
+                    .collect::<Vec<wasmer_runtime::Value>>(),
+            )
+            .map(|rets| rets.iter().map(wval_to_general_wval).collect())
+    }
+}
+
+struct FuncSigConverter<'a, T>(&'a T);
+
+impl<'a> From<FuncSigConverter<'a, FuncSig>> for WasmerFuncSig {
+    fn from(sig: FuncSigConverter<'a, FuncSig>) -> Self {
+        let params = sig
+            .0
+            .params()
+            .map(type_converters::general_wtype_to_wtype)
+            .collect::<Vec<_>>();
+        let returns = sig
+            .0
+            .returns()
+            .map(type_converters::general_wtype_to_wtype)
+            .collect::<Vec<_>>();
+        Self::new(params, returns)
+    }
+}
+
+impl<'a> From<FuncSigConverter<'a, WasmerFuncSig>> for FuncSig {
+    fn from(sig: FuncSigConverter<'a, WasmerFuncSig>) -> Self {
+        let params = sig
+            .0
+            .params()
+            .iter()
+            .map(type_converters::wtype_to_general_wtype)
+            .collect::<Vec<_>>();
+        let returns = sig
+            .0
+            .returns()
+            .iter()
+            .map(type_converters::wtype_to_general_wtype)
+            .collect::<Vec<_>>();
+        Self::new(params, returns)
     }
 }
diff --git a/crates/wasmer-backend/src/type_converters.rs b/crates/wasmer-backend/src/type_converters.rs
new file mode 100644
index 00000000..35139f0c
--- /dev/null
+++ b/crates/wasmer-backend/src/type_converters.rs
@@ -0,0 +1,65 @@
+/*
+ * Copyright 2020 Fluence Labs Limited
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *     http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+/// Contains converters of types and values between Wasmer and wasmer_interface_types.
+use wasmer_runtime::Value as WValue;
+use wasmer_runtime::types::Type as WType;
+
+use marine_wasm_backend_traits::WValue as GeneralWValue;
+use marine_wasm_backend_traits::WType as GeneralWType;
+
+pub(super) fn wtype_to_general_wtype(ty: &WType) -> GeneralWType {
+    match ty {
+        WType::I32 => GeneralWType::I32,
+        WType::I64 => GeneralWType::I64,
+        WType::F32 => GeneralWType::F32,
+        WType::F64 => GeneralWType::F64,
+        WType::V128 => unimplemented!(),
+    }
+}
+
+pub(super) fn general_wtype_to_wtype(ty: &GeneralWType) -> WType {
+    match ty {
+        GeneralWType::I32 => WType::I32,
+        GeneralWType::I64 => WType::I64,
+        GeneralWType::F32 => WType::F32,
+        GeneralWType::F64 => WType::F64,
+        ty => {
+            eprintln!("trying to convert {:?}", ty);
+            unimplemented!()
+        }
+    }
+}
+
+pub(super) fn general_wval_to_wval(value: &GeneralWValue) -> WValue {
+    match value {
+        GeneralWValue::I32(v) => WValue::I32(*v),
+        GeneralWValue::I64(v) => WValue::I64(*v),
+        GeneralWValue::F32(v) => WValue::F32(*v),
+        GeneralWValue::F64(v) => WValue::F64(*v),
+        _ => unimplemented!(),
+    }
+}
+
+pub(super) fn wval_to_general_wval(value: &WValue) -> GeneralWValue {
+    match value {
+        WValue::I32(v) => GeneralWValue::I32(*v),
+        WValue::I64(v) => GeneralWValue::I64(*v),
+        WValue::F32(v) => GeneralWValue::F32(*v),
+        WValue::F64(v) => GeneralWValue::F64(*v),
+        _ => unimplemented!(),
+    }
+}
diff --git a/crates/wasmer-backend/src/wasm_type_list.rs b/crates/wasmer-backend/src/wasm_type_list.rs
new file mode 100644
index 00000000..51af0ffe
--- /dev/null
+++ b/crates/wasmer-backend/src/wasm_type_list.rs
@@ -0,0 +1,448 @@
+use std::ptr::NonNull;
+use wasmer_core::error::RuntimeError;
+use wasmer_core::typed_func::{Wasm};
+use wasmer_core::types::{NativeWasmType, Type};
+use wasmer_core::vm::Ctx;
+use marine_wasm_backend_traits::WType;
+use marine_wasm_backend_traits::WValue;
+use marine_wasm_backend_traits::Tuple;
+use marine_wasm_backend_traits::WasmTypeList;
+
+
+struct Helper<T: WasmTypeList> (T);
+
+
+
+impl<T: WasmTypeList> wasmer_core::typed_func::WasmTypeList for Helper<T> {
+    type CStruct = T::CStruct;
+    type RetArray = T::RetArray;
+
+    fn from_ret_array(array: Self::RetArray) -> Self {
+        Self(T::from_ret_array(array))
+    }
+
+    fn empty_ret_array() -> Self::RetArray {
+        T::empty_ret_array()
+    }
+
+    fn from_c_struct(c_struct: Self::CStruct) -> Self {
+        Self(T::from_c_struct(c_struct))
+    }
+
+    fn into_c_struct(self) -> Self::CStruct {
+        self.into_c_struct()
+    }
+
+    fn types() -> &'static [Type] {
+        T::types() /// how to convert?
+    }
+
+    unsafe fn call<Rets>(self,
+                         f: NonNull<wasmer_core::prelude::vm::Func>,
+                         wasm: Wasm,
+                         ctx: *mut Ctx
+    ) -> Result<Rets, RuntimeError> where Rets: wasmer_core::typed_func::WasmTypeList {
+        // how to implement?
+    }
+}
+/*
+const fn gen_types(wtypes: &'static [WType]) -> &'static [Type] {
+    let types = [Type::I32; wtypes.len()];
+    &types
+}
+
+macro_rules! impl_traits {
+    ( [$repr:ident] $struct_name:ident, $( $x:ident ),* ) => {
+        /// Struct for typed funcs.
+        #[repr($repr)]
+        pub struct $struct_name< $( $x ),* > ( $( <$x as WasmExternType>::Native ),* )
+        where
+            $( $x: WasmExternType ),*;
+
+        #[allow(unused_parens)]
+        impl< $( $x ),* > wasmer_core::typed_func::WasmTypeList for Helper<( $( $x ),* )>
+        where
+            $( $x: WasmExternType ),*
+        {
+            type CStruct = $struct_name<$( $x ),*>;
+
+            type RetArray = [u64; count_idents!( $( $x ),* )];
+
+            fn from_ret_array(array: Self::RetArray) -> Self {
+                #[allow(non_snake_case)]
+                let [ $( $x ),* ] = array;
+
+                ( $( WasmExternType::from_native(NativeWasmType::from_binary($x)) ),* )
+            }
+
+            fn empty_ret_array() -> Self::RetArray {
+                [0; count_idents!( $( $x ),* )]
+            }
+
+            fn from_c_struct(c_struct: Self::CStruct) -> Self {
+                #[allow(non_snake_case)]
+                let $struct_name ( $( $x ),* ) = c_struct;
+
+                ( $( WasmExternType::from_native($x) ),* )
+            }
+
+            #[allow(unused_parens, non_snake_case)]
+            fn into_c_struct(self) -> Self::CStruct {
+                let ( $( $x ),* ) = self;
+
+                $struct_name ( $( WasmExternType::to_native($x) ),* )
+            }
+
+            fn types() -> &'static [Type] {
+                &[$( $x::Native::WTYPE ),*]
+            }
+
+            /*
+            #[allow(unused_parens, non_snake_case)]
+            unsafe fn call<Rets>(
+                self,
+                f: NonNull<vm::Func>,
+                wasm: Wasm,
+                ctx: *mut vm::Ctx,
+            ) -> Result<Rets, RuntimeError>
+            where
+                Rets: WasmTypeList
+            {
+                let ( $( $x ),* ) = self;
+                let args = [ $( $x.to_native().to_binary()),* ];
+                let mut rets = Rets::empty_ret_array();
+                let mut error_out = None;
+
+                if (wasm.invoke)(
+                    wasm.trampoline,
+                    ctx,
+                    f,
+                    args.as_ptr(),
+                    rets.as_mut().as_mut_ptr(),
+                    &mut error_out,
+                    wasm.invoke_env
+                ) {
+                    Ok(Rets::from_ret_array(rets))
+                } else {
+                    Err(error_out.map_or_else(|| RuntimeError::InvokeError(InvokeError::FailedWithNoError), Into::into))
+                }
+            }*/
+        }
+/*
+        #[allow(unused_parens)]
+        impl< $( $x, )* Rets, Trap, FN > HostFunction<ExplicitVmCtx, ( $( $x ),* ), Rets> for FN
+        where
+            $( $x: WasmExternType, )*
+            Rets: WasmTypeList,
+            Trap: TrapEarly<Rets>,
+            FN: Fn(&mut vm::Ctx $( , $x )*) -> Trap + 'static + Send,
+        {
+            #[allow(non_snake_case)]
+            fn to_raw(self) -> (NonNull<vm::Func>, Option<NonNull<vm::FuncEnv>>) {
+                // The `wrap` function is a wrapper around the
+                // imported function. It manages the argument passed
+                // to the imported function (in this case, the
+                // `vmctx` along with the regular WebAssembly
+                // arguments), and it manages the trapping.
+                //
+                // It is also required for the LLVM backend to be
+                // able to unwind through this function.
+                extern fn wrap<$( $x, )* Rets, Trap, FN>(
+                    vmctx: &vm::Ctx $( , $x: <$x as WasmExternType>::Native )*
+                ) -> Rets::CStruct
+                where
+                    $( $x: WasmExternType, )*
+                    Rets: WasmTypeList,
+                    Trap: TrapEarly<Rets>,
+                    FN: Fn(&mut vm::Ctx, $( $x, )*) -> Trap,
+                {
+                    // Get the pointer to this `wrap` function.
+                    let self_pointer = wrap::<$( $x, )* Rets, Trap, FN> as *const vm::Func;
+
+                    // Get the collection of imported functions.
+                    let vm_imported_functions = unsafe { &(*vmctx.import_backing).vm_functions };
+
+                    // Retrieve the `vm::FuncCtx`.
+                    let mut func_ctx: NonNull<vm::FuncCtx> = vm_imported_functions
+                        .iter()
+                        .find_map(|(_, imported_func)| {
+                            if imported_func.func == self_pointer {
+                                Some(imported_func.func_ctx)
+                            } else {
+                                None
+                            }
+                        })
+                        .expect("Import backing is not well-formed, cannot find `func_ctx`.");
+                    let func_ctx = unsafe { func_ctx.as_mut() };
+
+                    // Extract `vm::Ctx` from `vm::FuncCtx`. The
+                    // pointer is always non-null.
+                    let vmctx = unsafe { func_ctx.vmctx.as_mut() };
+
+                    // Extract `vm::FuncEnv` from `vm::FuncCtx`.
+                    let func_env = func_ctx.func_env;
+
+                    let func: &FN = match func_env {
+                        // The imported function is a regular
+                        // function, a closure without a captured
+                        // environment, or a closure with a captured
+                        // environment.
+                        Some(func_env) => unsafe {
+                            let func: NonNull<FN> = func_env.cast();
+
+                            &*func.as_ptr()
+                        },
+
+                        // This branch is supposed to be unreachable.
+                        None => unreachable!()
+                    };
+
+                    // Catch unwind in case of errors.
+                    let err = match panic::catch_unwind(
+                        panic::AssertUnwindSafe(
+                            || {
+                                func(vmctx $( , WasmExternType::from_native($x) )* ).report()
+                                //   ^^^^^ The imported function
+                                //         expects `vm::Ctx` as first
+                                //         argument; provide it.
+                            }
+                        )
+                    ) {
+                        Ok(Ok(returns)) => return returns.into_c_struct(),
+                        Ok(Err(err)) => {
+                            let b: Box<_> = err.into();
+                            RuntimeError::User(b as Box<dyn Any + Send>)
+                        },
+                        // TODO(blocking): this line is wrong!
+                        Err(err) => RuntimeError::User(err),
+                    };
+
+                    // At this point, there is an error that needs to
+                    // be trapped.
+                    unsafe {
+                        (&*vmctx.module).runnable_module.do_early_trap(err)
+                    }
+                }
+
+                // Extract the captured environment of the imported
+                // function if any.
+                let func_env: Option<NonNull<vm::FuncEnv>> =
+                    // `FN` is a function pointer, or a closure
+                    // _without_ a captured environment.
+                    if mem::size_of::<Self>() == 0 {
+                        NonNull::new(&self as *const _ as *mut vm::FuncEnv)
+                    }
+                    // `FN` is a closure _with_ a captured
+                    // environment.
+                    else {
+                        NonNull::new(Box::into_raw(Box::new(self))).map(NonNull::cast)
+                    };
+
+                (
+                    NonNull::new(wrap::<$( $x, )* Rets, Trap, Self> as *mut vm::Func).unwrap(),
+                    func_env
+                )
+            }
+        }
+
+        #[allow(unused_parens)]
+        impl< $( $x, )* Rets, Trap, FN > HostFunction<ImplicitVmCtx, ( $( $x ),* ), Rets> for FN
+        where
+            $( $x: WasmExternType, )*
+            Rets: WasmTypeList,
+            Trap: TrapEarly<Rets>,
+            FN: Fn($( $x, )*) -> Trap + 'static + Send,
+        {
+            #[allow(non_snake_case)]
+            fn to_raw(self) -> (NonNull<vm::Func>, Option<NonNull<vm::FuncEnv>>) {
+                // The `wrap` function is a wrapper around the
+                // imported function. It manages the argument passed
+                // to the imported function (in this case, only the
+                // regular WebAssembly arguments), and it manages the
+                // trapping.
+                //
+                // It is also required for the LLVM backend to be
+                // able to unwind through this function.
+                extern fn wrap<$( $x, )* Rets, Trap, FN>(
+                    vmctx: &vm::Ctx $( , $x: <$x as WasmExternType>::Native )*
+                ) -> Rets::CStruct
+                where
+                    $( $x: WasmExternType, )*
+                    Rets: WasmTypeList,
+                    Trap: TrapEarly<Rets>,
+                    FN: Fn($( $x, )*) -> Trap,
+                {
+                    // Get the pointer to this `wrap` function.
+                    let self_pointer = wrap::<$( $x, )* Rets, Trap, FN> as *const vm::Func;
+
+                    // Get the collection of imported functions.
+                    let vm_imported_functions = unsafe { &(*vmctx.import_backing).vm_functions };
+
+                    // Retrieve the `vm::FuncCtx`.
+                    let mut func_ctx: NonNull<vm::FuncCtx> = vm_imported_functions
+                        .iter()
+                        .find_map(|(_, imported_func)| {
+                            if imported_func.func == self_pointer {
+                                Some(imported_func.func_ctx)
+                            } else {
+                                None
+                            }
+                        })
+                        .expect("Import backing is not well-formed, cannot find `func_ctx`.");
+                    let func_ctx = unsafe { func_ctx.as_mut() };
+
+                    // Extract `vm::Ctx` from `vm::FuncCtx`. The
+                    // pointer is always non-null.
+                    let vmctx = unsafe { func_ctx.vmctx.as_mut() };
+
+                    // Extract `vm::FuncEnv` from `vm::FuncCtx`.
+                    let func_env = func_ctx.func_env;
+
+                    let func: &FN = match func_env {
+                        // The imported function is a regular
+                        // function, a closure without a captured
+                        // environment, or a closure with a captured
+                        // environment.
+                        Some(func_env) => unsafe {
+                            let func: NonNull<FN> = func_env.cast();
+
+                            &*func.as_ptr()
+                        },
+
+                        // This branch is supposed to be unreachable.
+                        None => unreachable!()
+                    };
+
+                    // Catch unwind in case of errors.
+                    let err = match panic::catch_unwind(
+                        panic::AssertUnwindSafe(
+                            || {
+                                func($( WasmExternType::from_native($x), )* ).report()
+                            }
+                        )
+                    ) {
+                        Ok(Ok(returns)) => return returns.into_c_struct(),
+                        Ok(Err(err)) => {
+                            let b: Box<_> = err.into();
+                            RuntimeError::User(b as Box<dyn Any + Send>)
+                        },
+                        // TODO(blocking): this line is wrong!
+                        Err(err) => RuntimeError::User(err),
+                    };
+
+                    // At this point, there is an error that needs to
+                    // be trapped.
+                    unsafe {
+                        (&*vmctx.module).runnable_module.do_early_trap(err)
+                    }
+                }
+
+                // Extract the captured environment of the imported
+                // function if any.
+                let func_env: Option<NonNull<vm::FuncEnv>> =
+                    // `FN` is a function pointer, or a closure
+                    // _without_ a captured environment.
+                    if mem::size_of::<Self>() == 0 {
+                        NonNull::new(&self as *const _ as *mut vm::FuncEnv)
+                    }
+                    // `FN` is a closure _with_ a captured
+                    // environment.
+                    else {
+                        NonNull::new(Box::into_raw(Box::new(self))).map(NonNull::cast)
+                    };
+
+                (
+                    NonNull::new(wrap::<$( $x, )* Rets, Trap, Self> as *mut vm::Func).unwrap(),
+                    func_env
+                )
+            }
+        }
+
+        #[allow(unused_parens)]
+        impl<'a $( , $x )*, Rets> Func<'a, ( $( $x ),* ), Rets, Wasm>
+        where
+            $( $x: WasmExternType, )*
+            Rets: WasmTypeList,
+        {
+            /// Call the typed func and return results.
+            #[allow(non_snake_case, clippy::too_many_arguments)]
+            pub fn call(&self, $( $x: $x, )* ) -> Result<Rets, RuntimeError> {
+                #[allow(unused_parens)]
+                unsafe {
+                    <( $( $x ),* ) as WasmTypeList>::call(
+                        ( $( $x ),* ),
+                        self.func,
+                        self.inner,
+                        self.vmctx
+                    )
+                }
+            }
+        }*/
+    };
+}
+
+macro_rules! count_idents {
+    ( $($idents:ident),* ) => {{
+        #[allow(dead_code, non_camel_case_types)]
+        enum Idents { $($idents,)* __CountIdentsLast }
+        const COUNT: usize = Idents::__CountIdentsLast as usize;
+        COUNT
+    }};
+}
+
+macro_rules! wasm_extern_type {
+    ($type:ty => $native_type:ty) => {
+        unsafe impl WasmExternType for $type {
+            type Native = $native_type;
+
+            fn from_native(native: Self::Native) -> Self {
+                native as _
+            }
+
+            fn to_native(self) -> Self::Native {
+                self as _
+            }
+        }
+    };
+}
+
+wasm_extern_type!(i8 => i32);
+wasm_extern_type!(u8 => i32);
+wasm_extern_type!(i16 => i32);
+wasm_extern_type!(u16 => i32);
+wasm_extern_type!(i32 => i32);
+wasm_extern_type!(u32 => i32);
+wasm_extern_type!(i64 => i64);
+wasm_extern_type!(u64 => i64);
+wasm_extern_type!(f32 => f32);
+wasm_extern_type!(f64 => f64);
+
+impl_traits!([C] S0,);
+impl_traits!([transparent] S1, A);
+impl_traits!([C] S2, A, B);
+impl_traits!([C] S3, A, B, C);
+impl_traits!([C] S4, A, B, C, D);
+impl_traits!([C] S5, A, B, C, D, E);
+impl_traits!([C] S6, A, B, C, D, E, F);
+impl_traits!([C] S7, A, B, C, D, E, F, G);
+impl_traits!([C] S8, A, B, C, D, E, F, G, H);
+impl_traits!([C] S9, A, B, C, D, E, F, G, H, I);
+impl_traits!([C] S10, A, B, C, D, E, F, G, H, I, J);
+impl_traits!([C] S11, A, B, C, D, E, F, G, H, I, J, K);
+impl_traits!([C] S12, A, B, C, D, E, F, G, H, I, J, K, L);
+impl_traits!([C] S13, A, B, C, D, E, F, G, H, I, J, K, L, M);
+impl_traits!([C] S14, A, B, C, D, E, F, G, H, I, J, K, L, M, N);
+impl_traits!([C] S15, A, B, C, D, E, F, G, H, I, J, K, L, M, N, O);
+impl_traits!([C] S16, A, B, C, D, E, F, G, H, I, J, K, L, M, N, O, P);
+impl_traits!([C] S17, A, B, C, D, E, F, G, H, I, J, K, L, M, N, O, P, Q);
+impl_traits!([C] S18, A, B, C, D, E, F, G, H, I, J, K, L, M, N, O, P, Q, R);
+impl_traits!([C] S19, A, B, C, D, E, F, G, H, I, J, K, L, M, N, O, P, Q, R, S);
+impl_traits!([C] S20, A, B, C, D, E, F, G, H, I, J, K, L, M, N, O, P, Q, R, S, T);
+impl_traits!([C] S21, A, B, C, D, E, F, G, H, I, J, K, L, M, N, O, P, Q, R, S, T, U);
+impl_traits!([C] S22, A, B, C, D, E, F, G, H, I, J, K, L, M, N, O, P, Q, R, S, T, U, V);
+impl_traits!([C] S23, A, B, C, D, E, F, G, H, I, J, K, L, M, N, O, P, Q, R, S, T, U, V, W);
+impl_traits!([C] S24, A, B, C, D, E, F, G, H, I, J, K, L, M, N, O, P, Q, R, S, T, U, V, W, X);
+impl_traits!([C] S25, A, B, C, D, E, F, G, H, I, J, K, L, M, N, O, P, Q, R, S, T, U, V, W, X, Y);
+impl_traits!([C] S26, A, B, C, D, E, F, G, H, I, J, K, L, M, N, O, P, Q, R, S, T, U, V, W, X, Y, Z);
+
+*/
\ No newline at end of file
diff --git a/runtime/src/host_imports/imports.rs b/runtime/src/host_imports/imports.rs
index f753ac8c..d3308789 100644
--- a/runtime/src/host_imports/imports.rs
+++ b/runtime/src/host_imports/imports.rs
@@ -31,8 +31,8 @@ use crate::HostImportDescriptor;
 //use wasmer_core::Func;
 //use wasmer_core::vm::Ctx;
 //use wasmer_core::typed_func::DynamicFunc;
-use wasmer_core::types::Value as WValue;
-use wasmer_core::types::FuncSig;
+//use wasmer_core::types::Value as WValue;
+//use wasmer_core::types::FuncSig;
 use it_lilo::lifter::ILifter;
 use it_lilo::lowerer::ILowerer;
 use it_memory_traits::Memory as ITMemory;
@@ -40,7 +40,7 @@ use it_memory_traits::Memory as ITMemory;
 use std::cell::RefCell;
 use std::rc::Rc;
 
-use marine_wasm_backend_traits::WasmBackend;
+use marine_wasm_backend_traits::{FuncSig, WasmBackend};
 use marine_wasm_backend_traits::DynamicFunc;
 use marine_wasm_backend_traits::ExportContext;
 
@@ -159,10 +159,7 @@ pub(crate) fn create_host_import_func<WB: WasmBackend>(
             }
         };
 
-    <WB as WasmBackend>::DynamicFunc::new(
-        std::sync::Arc::new(FuncSig::new(raw_args, raw_output)),
-        func,
-    )
+    <WB as WasmBackend>::DynamicFunc::new(FuncSig::new(raw_args, raw_output), func)
 }
 
 fn default_error_handler(err: &HostImportError) -> Option<crate::IValue> {
diff --git a/runtime/src/host_imports/mod.rs b/runtime/src/host_imports/mod.rs
index 58590b55..1aec60c6 100644
--- a/runtime/src/host_imports/mod.rs
+++ b/runtime/src/host_imports/mod.rs
@@ -26,8 +26,11 @@ use wasmer_core::Func;
 pub use errors::HostImportError;
 pub(crate) use imports::create_host_import_func;
 
-pub(self) use wasmer_core::types::Value as WValue;
-pub(self) use wasmer_core::types::Type as WType;
+//pub(self) use wasmer_core::types::Value as WValue;
+//pub(self) use wasmer_core::types::Type as WType;
+
+pub(self) use marine_wasm_backend_traits::WValue;
+pub(self) use marine_wasm_backend_traits::WType;
 
 pub(self) type HostImportResult<T> = std::result::Result<T, HostImportError>;
 pub(self) type WasmModuleFunc<Args, Rets> = Box<RefCell<Option<Func<'static, Args, Rets>>>>;
diff --git a/runtime/src/module/marine_module.rs b/runtime/src/module/marine_module.rs
index 39ffd940..de7fe3a5 100644
--- a/runtime/src/module/marine_module.rs
+++ b/runtime/src/module/marine_module.rs
@@ -46,6 +46,8 @@ use std::convert::TryInto;
 use std::mem::MaybeUninit;
 use std::sync::Arc;
 use std::rc::Rc;
+//use wasmer_core::types::FuncSig;
+use marine_wasm_backend_traits::FuncSig;
 
 type ITInterpreter<WB> = Interpreter<
     ITInstance<WB>,
@@ -148,7 +150,7 @@ impl<WB: WasmBackend> MModule<WB> {
 
         // call _start to populate the WASI state of the module
         #[rustfmt::skip]
-        if let Ok(start_func) = wasmer_instance.exports().get_func_no_args::<'_,  ()>("_start") {
+        if let Ok(start_func) = wasmer_instance.exports().get_func_no_args_no_rets("_start") {
             start_func()?;
         }
 
@@ -326,15 +328,12 @@ impl<WB: WasmBackend> MModule<WB> {
             I1: Iterator<Item = &'a IType>,
             I2: Iterator<Item = &'b IType>,
         {
-            use wasmer_core::types::FuncSig;
+            //use wasmer_core::types::FuncSig;
             use super::type_converters::itype_to_wtype;
 
             let inputs = inputs.map(itype_to_wtype).collect::<Vec<_>>();
             let outputs = outputs.map(itype_to_wtype).collect::<Vec<_>>();
-            <WB as WasmBackend>::DynamicFunc::new(
-                Arc::new(FuncSig::new(inputs, outputs)),
-                raw_import,
-            )
+            <WB as WasmBackend>::DynamicFunc::new(FuncSig::new(inputs, outputs), raw_import)
         }
 
         // creates a closure that is represent a IT module import
diff --git a/runtime/src/module/memory.rs b/runtime/src/module/memory.rs
deleted file mode 100644
index 88bb8c01..00000000
--- a/runtime/src/module/memory.rs
+++ /dev/null
@@ -1,108 +0,0 @@
-/*
- * Copyright 2020 Fluence Labs Limited
- *
- * Licensed under the Apache License, Version 2.0 (the "License");
- * you may not use this file except in compliance with the License.
- * You may obtain a copy of the License at
- *
- *     http://www.apache.org/licenses/LICENSE-2.0
- *
- * Unless required by applicable law or agreed to in writing, software
- * distributed under the License is distributed on an "AS IS" BASIS,
- * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
- * See the License for the specific language governing permissions and
- * limitations under the License.
- */
-
-use std::cell::Cell;
-use std::ops::Deref;
-use wasmer_it::interpreter::wasm;
-use wasmer_core::memory::{Memory, MemoryView};
-use wasmer_core::vm::LocalMemory;
-use crate::module::WasmerSequentialReader;
-
-use crate::module::WasmerSequentialWriter;
-
-use it_memory_traits::{MemoryAccessError};
-
-pub(crate) struct WITMemoryView<'a>(pub(crate) MemoryView<'a, u8>);
-
-#[derive(Clone)]
-pub(crate) struct WITMemory(pub(super) Memory);
-impl std::ops::Deref for WITMemory {
-    type Target = Memory;
-
-    fn deref(&self) -> &Self::Target {
-        &self.0
-    }
-}
-
-impl WITMemoryView<'_> {
-    fn check_bounds(
-        &self,
-        offset: usize,
-        size: usize,
-        memory_size: usize,
-    ) -> Result<(), MemoryAccessError> {
-        if offset + size >= memory_size {
-            Err(MemoryAccessError::OutOfBounds {
-                offset,
-                size,
-                memory_size,
-            })
-        } else {
-            Ok(())
-        }
-    }
-}
-
-impl<'s, 'v> wasm::structures::SequentialMemoryView<'v> for WITMemoryView<'s> {
-    type SR = WasmerSequentialReader<'v>;
-    type SW = WasmerSequentialWriter<'v>;
-
-    fn sequential_writer(
-        &'v self,
-        offset: usize,
-        size: usize,
-    ) -> Result<Self::SW, MemoryAccessError> {
-        let view = &self.0;
-        let slice = view.deref();
-
-        self.check_bounds(offset, size, slice.len())?;
-
-        let writer = WasmerSequentialWriter {
-            offset,
-            slice,
-            current_offset: Cell::new(offset),
-        };
-
-        Ok(writer)
-    }
-
-    fn sequential_reader(
-        &'v self,
-        offset: usize,
-        size: usize,
-    ) -> Result<Self::SR, MemoryAccessError> {
-        let view = &self.0;
-        let slice: &[Cell<u8>] = view.deref();
-
-        self.check_bounds(offset, size, slice.len())?;
-
-        let reader = WasmerSequentialReader {
-            memory: slice,
-            offset: Cell::new(offset),
-        };
-
-        Ok(reader)
-    }
-}
-
-impl<'a> wasm::structures::Memory<WITMemoryView<'a>> for WITMemory {
-    fn view(&self) -> WITMemoryView<'a> {
-        let LocalMemory { base, .. } = unsafe { *self.0.vm_local_memory() };
-        let length = self.0.size().bytes().0 / std::mem::size_of::<u8>();
-
-        unsafe { WITMemoryView(MemoryView::new(base as _, length as u32)) }
-    }
-}
diff --git a/runtime/src/module/memory_access.rs b/runtime/src/module/memory_access.rs
deleted file mode 100644
index 354d6a2b..00000000
--- a/runtime/src/module/memory_access.rs
+++ /dev/null
@@ -1,137 +0,0 @@
-use std::cell::Cell;
-use it_memory_traits::{SequentialReader, SequentialWriter};
-
-#[macro_export]
-macro_rules! value_der {
-    ($self:expr, $offset:expr, @seq_start $($ids:tt),* @seq_end) => {
-        [$($self.memory[$offset + $ids].get()),+]
-    };
-
-    ($self:expr, $offset:expr, 1) => {
-        crate::value_der!($self, $offset, @seq_start 0 @seq_end);
-    };
-
-    ($self:expr, $offset:expr, 2) => {
-        crate::value_der!($self, $offset, @seq_start 0, 1 @seq_end);
-    };
-
-    ($self:expr, $offset:expr, 4) => {
-        crate::value_der!($self, $offset, @seq_start 0, 1, 2, 3 @seq_end);
-    };
-
-    ($self:expr, $offset:expr, 8) => {
-        crate::value_der!($self, $offset, @seq_start 0, 1, 2, 3, 4, 5, 6, 7 @seq_end);
-    };
-
-    ($self:expr, $offset:expr, 16) => {
-        crate::value_der!($self, $offset, @seq_start 0, 1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15 @seq_end);
-    };
-}
-
-#[macro_export]
-macro_rules! read_ty {
-    ($func_name:ident, $ty:ty, 1) => {
-        fn $func_name(&self) -> $ty {
-            let offset = self.offset.get();
-            let result = <$ty>::from_le_bytes(crate::value_der!(self, offset, 1));
-
-            self.offset.set(offset + 1);
-            result
-        }
-    };
-
-    ($func_name:ident, $ty:ty, 2) => {
-        fn $func_name(&self) -> $ty {
-            let offset = self.offset.get();
-            let result = <$ty>::from_le_bytes(crate::value_der!(self, offset, 2));
-
-            self.offset.set(offset + 2);
-            result
-        }
-    };
-
-    ($func_name:ident, $ty:ty, 4) => {
-        fn $func_name(&self) -> $ty {
-            let offset = self.offset.get();
-            let result = <$ty>::from_le_bytes(crate::value_der!(self, offset, 4));
-
-            self.offset.set(offset + 4);
-            result
-        }
-    };
-
-    ($func_name:ident, $ty:ty, 8) => {
-        fn $func_name(&self) -> $ty {
-            let offset = self.offset.get();
-            let result = <$ty>::from_le_bytes(crate::value_der!(self, offset, 8));
-
-            self.offset.set(offset + 8);
-            result
-        }
-    };
-
-    ($func_name:ident, $ty:ty, 16) => {
-        fn $func_name(&self) -> $ty {
-            let offset = self.offset.get();
-            let result = <$ty>::from_le_bytes(crate::value_der!(self, offset, 16));
-
-            self.offset.set(offset + 16);
-            result
-        }
-    };
-}
-
-pub(crate) struct WasmerSequentialReader<'s> {
-    pub memory: &'s [Cell<u8>],
-    pub offset: Cell<usize>,
-}
-
-pub(crate) struct WasmerSequentialWriter<'s> {
-    pub offset: usize,
-    pub slice: &'s [Cell<u8>],
-    pub current_offset: Cell<usize>,
-}
-
-impl SequentialReader for WasmerSequentialReader<'_> {
-    fn read_byte(&self) -> u8 {
-        let offset = self.offset.get();
-        let result = self.memory[offset].get();
-        self.offset.set(offset + 1);
-        result
-    }
-
-    // needed because clippy suggests using an iterator which looks worse
-    #[allow(clippy::needless_range_loop)]
-    fn read_bytes<const COUNT: usize>(&self) -> [u8; COUNT] {
-        let offset = self.offset.get();
-        let mut result = [0u8; COUNT];
-        for index in 0..COUNT {
-            result[index] = self.memory[offset + index].get();
-        }
-
-        self.offset.set(offset + COUNT);
-        result
-    }
-}
-
-impl SequentialWriter for WasmerSequentialWriter<'_> {
-    fn start_offset(&self) -> usize {
-        self.offset
-    }
-
-    fn write_u8(&self, value: u8) {
-        let offset = self.current_offset.get();
-        self.slice[offset].set(value);
-        self.current_offset.set(offset + 1);
-    }
-
-    fn write_u32(&self, value: u32) {
-        self.write_bytes(&value.to_le_bytes());
-    }
-
-    fn write_bytes(&self, bytes: &[u8]) {
-        for byte in bytes {
-            self.write_u8(*byte)
-        }
-    }
-}
diff --git a/runtime/src/module/mod.rs b/runtime/src/module/mod.rs
index 724fa375..cd22990d 100644
--- a/runtime/src/module/mod.rs
+++ b/runtime/src/module/mod.rs
@@ -46,8 +46,10 @@ pub struct MFunctionSignature {
 }
 
 pub(crate) use marine_module::MModule;
-pub(self) use wasmer_core::types::Type as WType;
-pub(self) use wasmer_core::types::Value as WValue;
+//pub(self) use wasmer_core::types::Type as WType;
+//pub(self) use wasmer_core::types::Value as WValue;
+//pub(self) use marine_wasm_backend_traits::WType;
+pub(self) use marine_wasm_backend_traits::WValue;
 
 // types that often used together
 pub(crate) mod wit_prelude {
diff --git a/runtime/src/module/type_converters.rs b/runtime/src/module/type_converters.rs
index 6c1a1730..e00afdb3 100644
--- a/runtime/src/module/type_converters.rs
+++ b/runtime/src/module/type_converters.rs
@@ -15,7 +15,10 @@
  */
 
 /// Contains converters of types and values between Wasmer and wasmer_interface_types.
-use super::{WType, WValue, IType, IValue};
+use super::{IType, IValue};
+
+use marine_wasm_backend_traits::WType;
+use marine_wasm_backend_traits::WValue;
 
 pub(super) fn wtype_to_itype(ty: &WType) -> IType {
     match ty {
@@ -23,7 +26,7 @@ pub(super) fn wtype_to_itype(ty: &WType) -> IType {
         WType::I64 => IType::I64,
         WType::F32 => IType::F32,
         WType::F64 => IType::F64,
-        WType::V128 => unimplemented!(),
+        //WType::V128 => unimplemented!(),
     }
 }
 
@@ -64,6 +67,6 @@ pub(super) fn wval_to_ival(value: &WValue) -> IValue {
         WValue::I64(v) => IValue::I64(*v),
         WValue::F32(v) => IValue::F32(*v),
         WValue::F64(v) => IValue::F64(*v),
-        _ => unimplemented!(),
+        //_ => unimplemented!(),
     }
 }
diff --git a/runtime/src/module/wit_function.rs b/runtime/src/module/wit_function.rs
index 1b342b94..cb0df5fc 100644
--- a/runtime/src/module/wit_function.rs
+++ b/runtime/src/module/wit_function.rs
@@ -15,14 +15,14 @@
  */
 
 use super::marine_module::MModule;
-use super::{IType, IFunctionArg, IValue, WValue};
+use super::{IType, IFunctionArg, IValue};
 use super::marine_module::Callable;
 use crate::MResult;
 
-use marine_wasm_backend_traits::WasmBackend;
+use marine_wasm_backend_traits::{WasmBackend, WValue};
+use marine_wasm_backend_traits::ExportedDynFunc;
 
 use wasmer_it::interpreter::wasm;
-use wasmer_core::instance::DynFunc;
 
 // use std::sync::Arc;
 use std::rc::Rc;
@@ -30,7 +30,7 @@ use std::rc::Rc;
 #[derive(Clone)]
 enum WITFunctionInner<WB: WasmBackend> {
     Export {
-        func: Rc<DynFunc<'static>>,
+        func: Rc<<WB as WasmBackend>::ExportedDynFunc>,
     },
     Import {
         // TODO: use dyn Callable here
@@ -49,24 +49,22 @@ pub(super) struct WITFunction<WB: WasmBackend> {
 
 impl<WB: WasmBackend> WITFunction<WB> {
     /// Creates functions from a "usual" (not IT) module export.
-    pub(super) fn from_export(dyn_func: DynFunc<'static>, name: String) -> MResult<Self> {
+    pub(super) fn from_export(
+        dyn_func: <WB as WasmBackend>::ExportedDynFunc,
+        name: String,
+    ) -> MResult<Self> {
         use super::type_converters::wtype_to_itype;
 
         let signature = dyn_func.signature();
         let arguments = signature
             .params()
-            .iter()
             .map(|wtype| IFunctionArg {
                 // here it's considered as an anonymous arguments
                 name: String::new(),
                 ty: wtype_to_itype(wtype),
             })
             .collect::<Vec<_>>();
-        let outputs = signature
-            .returns()
-            .iter()
-            .map(wtype_to_itype)
-            .collect::<Vec<_>>();
+        let outputs = signature.returns().map(wtype_to_itype).collect::<Vec<_>>();
 
         let inner = WITFunctionInner::Export {
             func: Rc::new(dyn_func),
@@ -128,14 +126,20 @@ impl<WB: WasmBackend> wasm::structures::LocalImport for WITFunction<WB> {
     }
 
     fn call(&self, arguments: &[IValue]) -> std::result::Result<Vec<IValue>, ()> {
-        use super::type_converters::{ival_to_wval, wval_to_ival};
-
+        use super::type_converters::wval_to_ival;
+        use super::type_converters::ival_to_wval;
         match &self.inner {
             WITFunctionInner::Export { func, .. } => func
                 .as_ref()
-                .call(&arguments.iter().map(ival_to_wval).collect::<Vec<WValue>>())
-                .map(|result| result.iter().map(wval_to_ival).collect())
-                .map_err(|_| ()),
+                .call(
+                    arguments
+                        .iter()
+                        .map(ival_to_wval)
+                        .collect::<Vec<WValue>>()
+                        .as_slice(),
+                )
+                .map_err(|_| ())
+                .map(|results| results.iter().map(wval_to_ival).collect()),
             WITFunctionInner::Import { callable, .. } => Rc::make_mut(&mut callable.clone())
                 .call(arguments)
                 .map_err(|_| ()),
diff --git a/runtime/src/module/wit_instance.rs b/runtime/src/module/wit_instance.rs
index abec2314..92bffdd1 100644
--- a/runtime/src/module/wit_instance.rs
+++ b/runtime/src/module/wit_instance.rs
@@ -78,24 +78,16 @@ impl<WB: WasmBackend> ITInstance<WB> {
         wasmer_instance: &<WB as WasmBackend>::I,
         it: &MITInterfaces<'_>,
     ) -> MResult<HashMap<usize, WITFunction<WB>>> {
-        use wasmer_core::DynFunc;
-
         let module_exports = &wasmer_instance.exports();
 
         it.exports()
             .enumerate()
             .map(|(export_id, export)| {
-                let export_func = module_exports.get(export.name)?;
-                unsafe {
-                    // TODO: refactor this with new Wasmer API when it is ready
-                    // here it is safe because dyn func is never lives WITInstance
-                    let export_func =
-                        std::mem::transmute::<DynFunc<'_>, DynFunc<'static>>(export_func);
-                    Ok((
-                        export_id,
-                        WITFunction::from_export(export_func, export.name.to_string())?,
-                    ))
-                }
+                let export_func = module_exports.get_dyn_func(export.name)?;
+                Ok((
+                    export_id,
+                    WITFunction::from_export(export_func, export.name.to_string())?,
+                ))
             })
             .collect()
     }