diff --git a/nac3artiq/src/codegen.rs b/nac3artiq/src/codegen.rs
index ff1aba1..dca6adb 100644
--- a/nac3artiq/src/codegen.rs
+++ b/nac3artiq/src/codegen.rs
@@ -735,7 +735,9 @@ fn format_rpc_ret<'ctx>(
                 );
             }
 
-            ndarray.create_data(ctx, llvm_elem_ty, num_elements);
+            unsafe {
+                ndarray.create_data(generator, ctx, llvm_elem_ty, num_elements);
+            }
 
             let ndarray_data = ndarray.data().base_ptr(ctx, generator);
             let ndarray_data_i8 =
diff --git a/nac3core/src/codegen/expr.rs b/nac3core/src/codegen/expr.rs
index 1f92075..f96693c 100644
--- a/nac3core/src/codegen/expr.rs
+++ b/nac3core/src/codegen/expr.rs
@@ -2858,7 +2858,9 @@ fn gen_ndarray_subscript_expr<'ctx, G: CodeGenerator>(
                     .builder
                     .build_int_z_extend_or_bit_cast(ndarray_num_elems, sizeof_elem.get_type(), "")
                     .unwrap();
-                ndarray.create_data(ctx, llvm_ndarray_data_t, ndarray_num_elems);
+                unsafe {
+                    ndarray.create_data(generator, ctx, llvm_ndarray_data_t, ndarray_num_elems);
+                }
 
                 let v_data_src_ptr = v.data().ptr_offset(ctx, generator, &index_addr, None);
                 call_memcpy_generic(
@@ -3604,3 +3606,97 @@ pub fn gen_expr<'ctx, G: CodeGenerator>(
         _ => unimplemented!(),
     }))
 }
+
+/// Creates a function in the current module and inserts a `call` instruction into the LLVM IR.
+pub fn create_fn_and_call<'ctx>(
+    ctx: &CodeGenContext<'ctx, '_>,
+    fn_name: &str,
+    ret_type: Option<BasicTypeEnum<'ctx>>,
+    (params, is_var_args): (&[BasicTypeEnum<'ctx>], bool),
+    args: &[BasicValueEnum<'ctx>],
+    call_value_name: Option<&str>,
+    configure: Option<&dyn Fn(&FunctionValue<'ctx>)>,
+) -> Option<BasicValueEnum<'ctx>> {
+    let intrinsic_fn = ctx.module.get_function(fn_name).unwrap_or_else(|| {
+        let params = params.iter()
+            .copied()
+            .map(BasicTypeEnum::into)
+            .collect_vec();
+        let fn_type = if let Some(ret_type) = ret_type {
+            ret_type.fn_type(params.as_slice(), is_var_args)
+        } else {
+            ctx.ctx.void_type().fn_type(params.as_slice(), is_var_args)
+        };
+
+        ctx.module.add_function(fn_name, fn_type, None)
+    });
+
+    if let Some(configure) = configure {
+        configure(&intrinsic_fn);
+    }
+
+    let args = args.iter()
+        .copied()
+        .map(BasicValueEnum::into)
+        .collect_vec();
+    ctx.builder
+        .build_call(intrinsic_fn, args.as_slice(), call_value_name.unwrap_or_default())
+        .map(CallSiteValue::try_as_basic_value)
+        .map(Either::left)
+        .unwrap()
+}
+
+/// Creates a function in the current module and inserts a `call` instruction into the LLVM IR.
+///
+/// This is a wrapper around [`create_fn_and_call`] for non-vararg function. This function allows
+/// parameters and arguments to be specified as tuples to better indicate the expected type and 
+/// actual value of each parameter-argument pair of the call.
+pub fn create_and_call_function<'ctx>(
+    ctx: &CodeGenContext<'ctx, '_>,
+    fn_name: &str,
+    ret_type: Option<BasicTypeEnum<'ctx>>,
+    params: &[(BasicTypeEnum<'ctx>, BasicValueEnum<'ctx>)],
+    value_name: Option<&str>,
+    configure: Option<&dyn Fn(&FunctionValue<'ctx>)>,
+) -> Option<BasicValueEnum<'ctx>> {
+    let param_tys = params.iter().map(|(ty, _)| ty).copied().map(BasicTypeEnum::into).collect_vec();
+    let arg_values = params.iter().map(|(_, value)| value).copied().map(BasicValueEnum::into).collect_vec();
+
+    create_fn_and_call(
+        ctx,
+        fn_name,
+        ret_type,
+        (param_tys.as_slice(), false),
+        arg_values.as_slice(),
+        value_name,
+        configure,
+    )
+}
+
+/// Creates a function in the current module and inserts a `call` instruction into the LLVM IR.
+///
+/// This is a wrapper around [`create_fn_and_call`] for non-vararg function. This function allows
+/// only arguments to be specified and performs inference for the parameter types using
+/// [`BasicValueEnum::get_type`].
+pub fn infer_and_call_function<'ctx>(
+    ctx: &CodeGenContext<'ctx, '_>,
+    fn_name: &str,
+    ret_type: Option<BasicTypeEnum<'ctx>>,
+    args: &[BasicValueEnum<'ctx>],
+    value_name: Option<&str>,
+    configure: Option<&dyn Fn(&FunctionValue<'ctx>)>,
+) -> Option<BasicValueEnum<'ctx>> {
+    let param_tys = args.iter()
+        .map(BasicValueEnum::get_type)
+        .collect_vec();
+
+    create_fn_and_call(
+        ctx,
+        fn_name,
+        ret_type,
+        (param_tys.as_slice(), false),
+        args,
+        value_name,
+        configure,
+    )
+}
diff --git a/nac3core/src/codegen/irrt/mod.rs b/nac3core/src/codegen/irrt/mod.rs
index f6c4a1e..6361df2 100644
--- a/nac3core/src/codegen/irrt/mod.rs
+++ b/nac3core/src/codegen/irrt/mod.rs
@@ -60,6 +60,27 @@ pub fn load_irrt<'ctx>(ctx: &'ctx Context, symbol_resolver: &dyn SymbolResolver)
     irrt_mod
 }
 
+/// Returns the name of a function which contains variants for 32-bit and 64-bit `size_t`.
+///
+/// - When [`TypeContext::size_type`] is 32-bits, the function name is `fn_name}`.
+/// - When [`TypeContext::size_type`] is 64-bits, the function name is `{fn_name}64`.
+#[must_use]
+pub fn get_usize_dependent_function_name<G: CodeGenerator + ?Sized>(
+    generator: &mut G,
+    ctx: &CodeGenContext<'_, '_>,
+    name: &str,
+) -> String {
+    let mut name = name.to_owned();
+    match generator.get_size_type(ctx.ctx).get_bit_width() {
+        32 => {}
+        64 => name.push_str("64"),
+        bit_width => {
+            panic!("Unsupported int type bit width {bit_width}, must be either 32-bits or 64-bits")
+        }
+    }
+    name
+}
+
 /// NOTE: the output value of the end index of this function should be compared ***inclusively***,
 /// because python allows `a[2::-1]`, whose semantic is `[a[2], a[1], a[0]]`, which is equivalent to
 /// NO numeric slice in python.
diff --git a/nac3core/src/codegen/irrt/ndarray/basic.rs b/nac3core/src/codegen/irrt/ndarray/basic.rs
index e52031d..23e1afd 100644
--- a/nac3core/src/codegen/irrt/ndarray/basic.rs
+++ b/nac3core/src/codegen/irrt/ndarray/basic.rs
@@ -1,134 +1,258 @@
-use crate::codegen::{CodeGenContext, CodeGenerator};
+use inkwell::{
+    values::{BasicValueEnum, IntValue, PointerValue},
+    AddressSpace,
+};
 
-/// Returns the name of a function which contains variants for 32-bit and 64-bit `size_t`.
-///
-/// - When [`TypeContext::size_type`] is 32-bits, the function name is `fn_name}`.
-/// - When [`TypeContext::size_type`] is 64-bits, the function name is `{fn_name}64`.
-#[must_use]
-pub fn get_usize_dependent_function_name<G: CodeGenerator + ?Sized>(
+use crate::codegen::{
+    expr::create_and_call_function,
+    irrt::get_usize_dependent_function_name,
+    types::NDArrayType,
+    values::{NDArrayValue, ProxyValue},
+    CodeGenContext, CodeGenerator,
+};
+
+pub fn call_nac3_ndarray_util_assert_shape_no_negative<'ctx, G: CodeGenerator + ?Sized>(
     generator: &mut G,
-    ctx: &CodeGenContext<'_, '_>,
-    name: &str,
-) -> String {
-    let mut name = name.to_owned();
-    match generator.get_size_type(ctx.ctx).get_bit_width() {
-        32 => {}
-        64 => name.push_str("64"),
-        bit_width => {
-            panic!("Unsupported int type bit width {bit_width}, must be either 32-bits or 64-bits")
-        }
-    }
-    name
+    ctx: &mut CodeGenContext<'ctx, '_>,
+    ndims: IntValue<'ctx>,
+    shape: PointerValue<'ctx>,
+) {
+    let llvm_usize = generator.get_size_type(ctx.ctx);
+    let llvm_pusize = llvm_usize.ptr_type(AddressSpace::default());
+
+    let name = get_usize_dependent_function_name(
+        generator,
+        ctx,
+        "__nac3_ndarray_util_assert_shape_no_negative",
+    );
+
+    create_and_call_function(
+        ctx,
+        &name,
+        Some(llvm_usize.into()),
+        &[(llvm_usize.into(), ndims.into()), (llvm_pusize.into(), shape.into())],
+        None,
+        None,
+    );
 }
 
-// pub fn call_nac3_ndarray_util_assert_shape_no_negative<'ctx, G: CodeGenerator + ?Sized>(
-//     generator: &mut G,
-//     ctx: &mut CodeGenContext<'ctx, '_>,
-//     ndims: Instance<'ctx, Int<SizeT>>,
-//     shape: Instance<'ctx, Ptr<Int<SizeT>>>,
-// ) {
-//     let name = get_usize_dependent_function_name(
-//         generator,
-//         ctx,
-//         "__nac3_ndarray_util_assert_shape_no_negative",
-//     );
-//     FnCall::builder(generator, ctx, &name).arg(ndims).arg(shape).returning_void();
-// }
-//
-// pub fn call_nac3_ndarray_util_assert_output_shape_same<'ctx, G: CodeGenerator + ?Sized>(
-//     generator: &mut G,
-//     ctx: &mut CodeGenContext<'ctx, '_>,
-//     ndarray_ndims: Instance<'ctx, Int<SizeT>>,
-//     ndarray_shape: Instance<'ctx, Ptr<Int<SizeT>>>,
-//     output_ndims: Instance<'ctx, Int<SizeT>>,
-//     output_shape: Instance<'ctx, Ptr<Int<SizeT>>>,
-// ) {
-//     let name = get_usize_dependent_function_name(
-//         generator,
-//         ctx,
-//         "__nac3_ndarray_util_assert_output_shape_same",
-//     );
-//     FnCall::builder(generator, ctx, &name)
-//         .arg(ndarray_ndims)
-//         .arg(ndarray_shape)
-//         .arg(output_ndims)
-//         .arg(output_shape)
-//         .returning_void();
-// }
-//
-// pub fn call_nac3_ndarray_size<'ctx, G: CodeGenerator + ?Sized>(
-//     generator: &mut G,
-//     ctx: &mut CodeGenContext<'ctx, '_>,
-//     ndarray: Instance<'ctx, Ptr<Struct<NDArray>>>,
-// ) -> Instance<'ctx, Int<SizeT>> {
-//     let name = get_usize_dependent_function_name(generator, ctx, "__nac3_ndarray_size");
-//     FnCall::builder(generator, ctx, &name).arg(ndarray).returning_auto("size")
-// }
-//
-// pub fn call_nac3_ndarray_nbytes<'ctx, G: CodeGenerator + ?Sized>(
-//     generator: &mut G,
-//     ctx: &mut CodeGenContext<'ctx, '_>,
-//     ndarray: Instance<'ctx, Ptr<Struct<NDArray>>>,
-// ) -> Instance<'ctx, Int<SizeT>> {
-//     let name = get_usize_dependent_function_name(generator, ctx, "__nac3_ndarray_nbytes");
-//     FnCall::builder(generator, ctx, &name).arg(ndarray).returning_auto("nbytes")
-// }
-//
-// pub fn call_nac3_ndarray_len<'ctx, G: CodeGenerator + ?Sized>(
-//     generator: &mut G,
-//     ctx: &mut CodeGenContext<'ctx, '_>,
-//     ndarray: Instance<'ctx, Ptr<Struct<NDArray>>>,
-// ) -> Instance<'ctx, Int<SizeT>> {
-//     let name = get_usize_dependent_function_name(generator, ctx, "__nac3_ndarray_len");
-//     FnCall::builder(generator, ctx, &name).arg(ndarray).returning_auto("len")
-// }
-//
-// pub fn call_nac3_ndarray_is_c_contiguous<'ctx, G: CodeGenerator + ?Sized>(
-//     generator: &mut G,
-//     ctx: &mut CodeGenContext<'ctx, '_>,
-//     ndarray: Instance<'ctx, Ptr<Struct<NDArray>>>,
-// ) -> Instance<'ctx, Int<Bool>> {
-//     let name = get_usize_dependent_function_name(generator, ctx, "__nac3_ndarray_is_c_contiguous");
-//     FnCall::builder(generator, ctx, &name).arg(ndarray).returning_auto("is_c_contiguous")
-// }
-//
-// pub fn call_nac3_ndarray_get_nth_pelement<'ctx, G: CodeGenerator + ?Sized>(
-//     generator: &mut G,
-//     ctx: &mut CodeGenContext<'ctx, '_>,
-//     ndarray: Instance<'ctx, Ptr<Struct<NDArray>>>,
-//     index: Instance<'ctx, Int<SizeT>>,
-// ) -> Instance<'ctx, Ptr<Int<Byte>>> {
-//     let name = get_usize_dependent_function_name(generator, ctx, "__nac3_ndarray_get_nth_pelement");
-//     FnCall::builder(generator, ctx, &name).arg(ndarray).arg(index).returning_auto("pelement")
-// }
-//
-// pub fn call_nac3_ndarray_get_pelement_by_indices<'ctx, G: CodeGenerator + ?Sized>(
-//     generator: &mut G,
-//     ctx: &mut CodeGenContext<'ctx, '_>,
-//     ndarray: Instance<'ctx, Ptr<Struct<NDArray>>>,
-//     indices: Instance<'ctx, Ptr<Int<SizeT>>>,
-// ) -> Instance<'ctx, Ptr<Int<Byte>>> {
-//     let name =
-//         get_usize_dependent_function_name(generator, ctx, "__nac3_ndarray_get_pelement_by_indices");
-//     FnCall::builder(generator, ctx, &name).arg(ndarray).arg(indices).returning_auto("pelement")
-// }
-//
-// pub fn call_nac3_ndarray_set_strides_by_shape<'ctx, G: CodeGenerator + ?Sized>(
-//     generator: &mut G,
-//     ctx: &mut CodeGenContext<'ctx, '_>,
-//     ndarray: Instance<'ctx, Ptr<Struct<NDArray>>>,
-// ) {
-//     let name =
-//         get_usize_dependent_function_name(generator, ctx, "__nac3_ndarray_set_strides_by_shape");
-//     FnCall::builder(generator, ctx, &name).arg(ndarray).returning_void();
-// }
-//
-// pub fn call_nac3_ndarray_copy_data<'ctx, G: CodeGenerator + ?Sized>(
-//     generator: &mut G,
-//     ctx: &mut CodeGenContext<'ctx, '_>,
-//     src_ndarray: Instance<'ctx, Ptr<Struct<NDArray>>>,
-//     dst_ndarray: Instance<'ctx, Ptr<Struct<NDArray>>>,
-// ) {
-//     let name = get_usize_dependent_function_name(generator, ctx, "__nac3_ndarray_copy_data");
-//     FnCall::builder(generator, ctx, &name).arg(src_ndarray).arg(dst_ndarray).returning_void();
-// }
+pub fn call_nac3_ndarray_util_assert_output_shape_same<'ctx, G: CodeGenerator + ?Sized>(
+    generator: &mut G,
+    ctx: &mut CodeGenContext<'ctx, '_>,
+    ndarray_ndims: IntValue<'ctx>,
+    ndarray_shape: PointerValue<'ctx>,
+    output_ndims: IntValue<'ctx>,
+    output_shape: IntValue<'ctx>,
+) {
+    let llvm_usize = generator.get_size_type(ctx.ctx);
+    let llvm_pusize = llvm_usize.ptr_type(AddressSpace::default());
+
+    let name = get_usize_dependent_function_name(
+        generator,
+        ctx,
+        "__nac3_ndarray_util_assert_output_shape_same",
+    );
+
+    create_and_call_function(
+        ctx,
+        &name,
+        Some(llvm_usize.into()),
+        &[
+            (llvm_usize.into(), ndarray_ndims.into()),
+            (llvm_pusize.into(), ndarray_shape.into()),
+            (llvm_usize.into(), output_ndims.into()),
+            (llvm_pusize.into(), output_shape.into()),
+        ],
+        None,
+        None,
+    );
+}
+
+pub fn call_nac3_ndarray_size<'ctx, G: CodeGenerator + ?Sized>(
+    generator: &mut G,
+    ctx: &mut CodeGenContext<'ctx, '_>,
+    ndarray: NDArrayValue<'ctx>,
+) -> IntValue<'ctx> {
+    let llvm_usize = generator.get_size_type(ctx.ctx);
+    let llvm_ndarray = NDArrayType::llvm_type(ctx.ctx, llvm_usize);
+
+    let name = get_usize_dependent_function_name(generator, ctx, "__nac3_ndarray_size");
+
+    create_and_call_function(
+        ctx,
+        &name,
+        Some(llvm_usize.into()),
+        &[(llvm_ndarray.into(), ndarray.as_base_value().into())],
+        Some("size"),
+        None,
+    )
+    .map(BasicValueEnum::into_int_value)
+    .unwrap()
+}
+
+pub fn call_nac3_ndarray_nbytes<'ctx, G: CodeGenerator + ?Sized>(
+    generator: &mut G,
+    ctx: &mut CodeGenContext<'ctx, '_>,
+    ndarray: NDArrayValue<'ctx>,
+) -> IntValue<'ctx> {
+    let llvm_usize = generator.get_size_type(ctx.ctx);
+    let llvm_ndarray = NDArrayType::llvm_type(ctx.ctx, llvm_usize);
+
+    let name = get_usize_dependent_function_name(generator, ctx, "__nac3_ndarray_nbytes");
+
+    create_and_call_function(
+        ctx,
+        &name,
+        Some(llvm_usize.into()),
+        &[(llvm_ndarray.into(), ndarray.as_base_value().into())],
+        Some("nbytes"),
+        None,
+    )
+    .map(BasicValueEnum::into_int_value)
+    .unwrap()
+}
+
+pub fn call_nac3_ndarray_len<'ctx, G: CodeGenerator + ?Sized>(
+    generator: &mut G,
+    ctx: &mut CodeGenContext<'ctx, '_>,
+    ndarray: NDArrayValue<'ctx>,
+) -> IntValue<'ctx> {
+    let llvm_usize = generator.get_size_type(ctx.ctx);
+    let llvm_ndarray = NDArrayType::llvm_type(ctx.ctx, llvm_usize);
+
+    let name = get_usize_dependent_function_name(generator, ctx, "__nac3_ndarray_len");
+
+    create_and_call_function(
+        ctx,
+        &name,
+        Some(llvm_usize.into()),
+        &[(llvm_ndarray.into(), ndarray.as_base_value().into())],
+        Some("len"),
+        None,
+    )
+    .map(BasicValueEnum::into_int_value)
+    .unwrap()
+}
+
+pub fn call_nac3_ndarray_is_c_contiguous<'ctx, G: CodeGenerator + ?Sized>(
+    generator: &mut G,
+    ctx: &mut CodeGenContext<'ctx, '_>,
+    ndarray: NDArrayValue<'ctx>,
+) -> IntValue<'ctx> {
+    let llvm_i1 = ctx.ctx.bool_type();
+    let llvm_usize = generator.get_size_type(ctx.ctx);
+    let llvm_ndarray = NDArrayType::llvm_type(ctx.ctx, llvm_usize);
+
+    let name = get_usize_dependent_function_name(generator, ctx, "__nac3_ndarray_is_c_contiguous");
+
+    create_and_call_function(
+        ctx,
+        &name,
+        Some(llvm_i1.into()),
+        &[(llvm_ndarray.into(), ndarray.as_base_value().into())],
+        Some("is_c_contiguous"),
+        None,
+    )
+    .map(BasicValueEnum::into_int_value)
+    .unwrap()
+}
+
+pub fn call_nac3_ndarray_get_nth_pelement<'ctx, G: CodeGenerator + ?Sized>(
+    generator: &mut G,
+    ctx: &mut CodeGenContext<'ctx, '_>,
+    ndarray: NDArrayValue<'ctx>,
+    index: IntValue<'ctx>,
+) -> PointerValue<'ctx> {
+    let llvm_i8 = ctx.ctx.i8_type();
+    let llvm_pi8 = llvm_i8.ptr_type(AddressSpace::default());
+    let llvm_usize = generator.get_size_type(ctx.ctx);
+    let llvm_ndarray = NDArrayType::llvm_type(ctx.ctx, llvm_usize);
+
+    let name = get_usize_dependent_function_name(generator, ctx, "__nac3_ndarray_get_nth_pelement");
+
+    create_and_call_function(
+        ctx,
+        &name,
+        Some(llvm_pi8.into()),
+        &[(llvm_ndarray.into(), ndarray.as_base_value().into()), (llvm_usize.into(), index.into())],
+        Some("pelement"),
+        None,
+    )
+    .map(BasicValueEnum::into_pointer_value)
+    .unwrap()
+}
+
+pub fn call_nac3_ndarray_get_pelement_by_indices<'ctx, G: CodeGenerator + ?Sized>(
+    generator: &mut G,
+    ctx: &mut CodeGenContext<'ctx, '_>,
+    ndarray: NDArrayValue<'ctx>,
+    indices: PointerValue<'ctx>,
+) -> PointerValue<'ctx> {
+    let llvm_i8 = ctx.ctx.i8_type();
+    let llvm_pi8 = llvm_i8.ptr_type(AddressSpace::default());
+    let llvm_usize = generator.get_size_type(ctx.ctx);
+    let llvm_pusize = llvm_usize.ptr_type(AddressSpace::default());
+    let llvm_ndarray = NDArrayType::llvm_type(ctx.ctx, llvm_usize);
+
+    let name =
+        get_usize_dependent_function_name(generator, ctx, "__nac3_ndarray_get_pelement_by_indices");
+
+    create_and_call_function(
+        ctx,
+        &name,
+        Some(llvm_pi8.into()),
+        &[
+            (llvm_ndarray.into(), ndarray.as_base_value().into()),
+            (llvm_pusize.into(), indices.into()),
+        ],
+        Some("pelement"),
+        None,
+    )
+    .map(BasicValueEnum::into_pointer_value)
+    .unwrap()
+}
+
+pub fn call_nac3_ndarray_set_strides_by_shape<'ctx, G: CodeGenerator + ?Sized>(
+    generator: &mut G,
+    ctx: &mut CodeGenContext<'ctx, '_>,
+    ndarray: NDArrayValue<'ctx>,
+) {
+    let llvm_usize = generator.get_size_type(ctx.ctx);
+    let llvm_ndarray = NDArrayType::llvm_type(ctx.ctx, llvm_usize);
+
+    let name =
+        get_usize_dependent_function_name(generator, ctx, "__nac3_ndarray_set_strides_by_shape");
+
+    create_and_call_function(
+        ctx,
+        &name,
+        None,
+        &[(llvm_ndarray.into(), ndarray.as_base_value().into())],
+        None,
+        None,
+    );
+}
+
+pub fn call_nac3_ndarray_copy_data<'ctx, G: CodeGenerator + ?Sized>(
+    generator: &mut G,
+    ctx: &mut CodeGenContext<'ctx, '_>,
+    src_ndarray: NDArrayValue<'ctx>,
+    dst_ndarray: NDArrayValue<'ctx>,
+) {
+    let llvm_usize = generator.get_size_type(ctx.ctx);
+    let llvm_ndarray = NDArrayType::llvm_type(ctx.ctx, llvm_usize);
+
+    let name = get_usize_dependent_function_name(generator, ctx, "__nac3_ndarray_copy_data");
+
+    create_and_call_function(
+        ctx,
+        &name,
+        None,
+        &[
+            (llvm_ndarray.into(), src_ndarray.as_base_value().into()),
+            (llvm_ndarray.into(), dst_ndarray.as_base_value().into()),
+        ],
+        None,
+        None,
+    );
+}
diff --git a/nac3core/src/codegen/numpy.rs b/nac3core/src/codegen/numpy.rs
index 92bab80..8f7eaca 100644
--- a/nac3core/src/codegen/numpy.rs
+++ b/nac3core/src/codegen/numpy.rs
@@ -212,7 +212,9 @@ fn ndarray_init_data<'ctx, G: CodeGenerator + ?Sized>(
         &ndarray.shape().as_slice_value(ctx, generator),
         (None, None),
     );
-    ndarray.create_data(ctx, llvm_ndarray_data_t, ndarray_num_elems);
+    unsafe {
+        ndarray.create_data(generator, ctx, llvm_ndarray_data_t, ndarray_num_elems);
+    }
 
     ndarray
 }
diff --git a/nac3core/src/codegen/types/ndarray.rs b/nac3core/src/codegen/types/ndarray.rs
index 9675313..9f94d0c 100644
--- a/nac3core/src/codegen/types/ndarray.rs
+++ b/nac3core/src/codegen/types/ndarray.rs
@@ -103,7 +103,7 @@ impl<'ctx> NDArrayType<'ctx> {
 
     /// Creates an LLVM type corresponding to the expected structure of an `NDArray`.
     #[must_use]
-    fn llvm_type(ctx: &'ctx Context, llvm_usize: IntType<'ctx>) -> PointerType<'ctx> {
+    pub fn llvm_type(ctx: &'ctx Context, llvm_usize: IntType<'ctx>) -> PointerType<'ctx> {
         // struct NDArray { data: i8*, itemsize: size_t, ndims: size_t, shape: size_t*, strides: size_t* }
         //
         // * data    : Pointer to an array containing the array data
@@ -142,11 +142,7 @@ impl<'ctx> NDArrayType<'ctx> {
         let llvm_dtype = ctx.get_llvm_type(generator, dtype);
         let llvm_usize = generator.get_size_type(ctx.ctx);
 
-        NDArrayType {
-            ty: Self::llvm_type(ctx.ctx, llvm_usize),
-            dtype: llvm_dtype,
-            llvm_usize,
-        }
+        NDArrayType { ty: Self::llvm_type(ctx.ctx, llvm_usize), dtype: llvm_dtype, llvm_usize }
     }
 
     /// Creates an [`NDArrayType`] from a [`PointerType`] representing an `NDArray`.
diff --git a/nac3core/src/codegen/values/ndarray.rs b/nac3core/src/codegen/values/ndarray.rs
index 96c03c4..23da965 100644
--- a/nac3core/src/codegen/values/ndarray.rs
+++ b/nac3core/src/codegen/values/ndarray.rs
@@ -184,8 +184,15 @@ impl<'ctx> NDArrayValue<'ctx> {
 
     /// Convenience method for creating a new array storing data elements with the given element
     /// type `elem_ty` and `size`.
-    pub fn create_data(
+    ///
+    /// The data buffer will be allocated on the stack, and is considered to be owned by this ndarray instance.
+    ///
+    /// # Safety
+    ///
+    /// `shape` and `itemsize` of the ndarray must be initialized.
+    pub unsafe fn create_data<G: CodeGenerator + ?Sized>(
         &self,
+        generator: &mut G,
         ctx: &CodeGenContext<'ctx, '_>,
         elem_ty: BasicTypeEnum<'ctx>,
         size: IntValue<'ctx>,
@@ -195,10 +202,10 @@ impl<'ctx> NDArrayValue<'ctx> {
         let nbytes = ctx.builder.build_int_mul(size, itemsize, "").unwrap();
 
         // TODO: What about alignment?
-        self.store_data(
-            ctx,
-            ctx.builder.build_array_alloca(ctx.ctx.i8_type(), nbytes, "").unwrap(),
-        );
+        let data = ctx.builder.build_array_alloca(ctx.ctx.i8_type(), nbytes, "").unwrap();
+        self.store_data(ctx, data);
+
+        // self.set_strides_contiguous(generator, ctx);
     }
 
     /// Returns a proxy object to the field storing the data of this `NDArray`.
@@ -206,6 +213,112 @@ impl<'ctx> NDArrayValue<'ctx> {
     pub fn data(&self) -> NDArrayDataProxy<'ctx, '_> {
         NDArrayDataProxy(self)
     }
+
+    /// Copy shape dimensions from an array.
+    pub fn copy_shape_from_array<G: CodeGenerator + ?Sized>(
+        &self,
+        generator: &mut G,
+        ctx: &mut CodeGenContext<'ctx, '_>,
+        shape: PointerValue<'ctx>,
+    ) {
+        todo!()
+    }
+
+    /// Copy shape dimensions from an ndarray.
+    /// Panics if `ndims` mismatches.
+    pub fn copy_shape_from_ndarray<G: CodeGenerator + ?Sized>(
+        &self,
+        generator: &mut G,
+        ctx: &mut CodeGenContext<'ctx, '_>,
+        src_ndarray: NDArrayValue<'ctx>,
+    ) {
+        todo!()
+    }
+
+    /// Copy strides dimensions from an array.
+    pub fn copy_strides_from_array<G: CodeGenerator + ?Sized>(
+        &self,
+        generator: &mut G,
+        ctx: &mut CodeGenContext<'ctx, '_>,
+        strides: PointerValue<'ctx>,
+    ) {
+        todo!()
+    }
+
+    /// Copy strides dimensions from an ndarray.
+    /// Panics if `ndims` mismatches.
+    pub fn copy_strides_from_ndarray<G: CodeGenerator + ?Sized>(
+        &self,
+        generator: &mut G,
+        ctx: &mut CodeGenContext<'ctx, '_>,
+        src_ndarray: NDArrayValue<'ctx>,
+    ) {
+        todo!()
+    }
+
+    /// Get the `np.size()` of this ndarray.
+    pub fn size<G: CodeGenerator + ?Sized>(
+        &self,
+        generator: &mut G,
+        ctx: &mut CodeGenContext<'ctx, '_>,
+    ) -> IntValue<'ctx> {
+        todo!()
+    }
+
+    /// Get the `ndarray.nbytes` of this ndarray.
+    pub fn nbytes<G: CodeGenerator + ?Sized>(
+        &self,
+        generator: &mut G,
+        ctx: &mut CodeGenContext<'ctx, '_>,
+    ) -> IntValue<'ctx> {
+        todo!()
+    }
+
+    /// Get the `len()` of this ndarray.
+    pub fn len<G: CodeGenerator + ?Sized>(
+        &self,
+        generator: &mut G,
+        ctx: &mut CodeGenContext<'ctx, '_>,
+    ) -> IntValue<'ctx> {
+        todo!()
+    }
+
+    /// Check if this ndarray is C-contiguous.
+    ///
+    /// See NumPy's `flags["C_CONTIGUOUS"]`: <https://numpy.org/doc/stable/reference/generated/numpy.ndarray.flags.html#numpy.ndarray.flags>
+    pub fn is_c_contiguous<G: CodeGenerator + ?Sized>(
+        &self,
+        generator: &mut G,
+        ctx: &mut CodeGenContext<'ctx, '_>,
+    ) -> IntValue<'ctx> {
+        todo!()
+    }
+
+    /// Call [`call_nac3_ndarray_set_strides_by_shape`] on this ndarray to update `strides`.
+    ///
+    /// Update the ndarray's strides to make the ndarray contiguous.
+    pub fn set_strides_contiguous<G: CodeGenerator + ?Sized>(
+        self,
+        generator: &mut G,
+        ctx: &CodeGenContext<'ctx, '_>,
+    ) {
+        todo!()
+    }
+
+    /// Copy data from another ndarray.
+    ///
+    /// This ndarray and `src` is that their `np.size()` should be the same. Their shapes
+    /// do not matter. The copying order is determined by how their flattened views look.
+    ///
+    /// Panics if the `dtype`s of ndarrays are different.
+    pub fn copy_data_from<G: CodeGenerator + ?Sized>(
+        &self,
+        generator: &mut G,
+        ctx: &mut CodeGenContext<'ctx, '_>,
+        src: NDArrayValue<'ctx>,
+    ) {
+        todo!()
+    }
 }
 
 impl<'ctx> ProxyValue<'ctx> for NDArrayValue<'ctx> {