diff --git a/nac3artiq/src/codegen.rs b/nac3artiq/src/codegen.rs
index 1ac9d407..d70f249a 100644
--- a/nac3artiq/src/codegen.rs
+++ b/nac3artiq/src/codegen.rs
@@ -549,6 +549,8 @@ fn rpc_codegen_callback_fn<'ctx>(
         ctx.builder.build_store(arg_slot, *arg).unwrap();
         let arg_slot = if matches!(&*ctx.unifier.get_ty_immutable(*arg_ty), TypeEnum::TObj { obj_id, .. } if *obj_id == PrimDef::NDArray.id())
         {
+            println!("Codegen for ndarray RPC");
+
             let (elem_ty, _) = unpack_ndarray_var_tys(&mut ctx.unifier, *arg_ty);
             let llvm_arg_ty =
                 NDArrayType::new(generator, ctx.ctx, ctx.get_llvm_type(generator, elem_ty));
@@ -557,6 +559,8 @@ fn rpc_codegen_callback_fn<'ctx>(
             let llvm_usize_sizeof = llvm_arg_ty.size_type().size_of();
             let llvm_elem_sizeof = llvm_arg_ty.element_type().size_of().unwrap();
 
+            println!("Calc required buffer size");
+
             let dims_buf_sz =
                 ctx.builder.build_int_mul(llvm_arg.load_ndims(ctx), llvm_usize_sizeof, "").unwrap();
             let data_buf_sz = ctx
@@ -570,9 +574,13 @@ fn rpc_codegen_callback_fn<'ctx>(
 
             let buffer_size = ctx.builder.build_int_add(dims_buf_sz, data_buf_sz, "").unwrap();
 
+            println!("Alloc buffer");
+
             let buffer =
                 generator.gen_array_var_alloc(ctx, int8.into(), buffer_size, None).unwrap();
 
+            println!("memcpy dim_sizes");
+
             llvm_intrinsics::call_memcpy_generic(
                 ctx,
                 buffer.base_ptr(ctx, generator),
@@ -581,6 +589,8 @@ fn rpc_codegen_callback_fn<'ctx>(
                 int1.const_zero(),
             );
 
+            println!("memcpy data");
+
             let pbuffer_data_begin =
                 unsafe { buffer.ptr_offset_unchecked(ctx, generator, &dims_buf_sz, None) };
             llvm_intrinsics::call_memcpy_generic(
@@ -591,6 +601,8 @@ fn rpc_codegen_callback_fn<'ctx>(
                 int1.const_zero(),
             );
 
+            println!("done");
+
             buffer.base_ptr(ctx, generator)
         } else {
             ctx.builder