diff --git a/rust/wasm-binding/src/rpc_rust_defined.rs b/rust/wasm-binding/src/rpc_rust_defined.rs
index 371b1e06..bcfc74eb 100644
--- a/rust/wasm-binding/src/rpc_rust_defined.rs
+++ b/rust/wasm-binding/src/rpc_rust_defined.rs
@@ -2,7 +2,7 @@ use crate::rpc_helpers::{decode, encode};
 use crate::rpc_proto_scaffolding::{database_query_generator_from_config, JsFileSystem};
 use crate::uint8_reader::Uint8ArrayReader;
 use js_sys::{Function, Promise, Uint8Array};
-use quary_core::chart::chart_file_from_yaml;
+use quary_core::chart::{chart_file_from_yaml, chart_file_to_yaml};
 use quary_core::database_snowflake::validate_snowfalke_account_identifier;
 use quary_core::test_runner::{
     run_model_tests_internal, run_tests_internal, RunStatementFunc, RunTestError,
@@ -13,6 +13,15 @@ use std::rc::Rc;
 use wasm_bindgen::prelude::*;
 use wasm_bindgen_futures::JsFuture;
 
+/// write chart file to Uint8Array string encodes a chart file in Uint8Array proto and returns it
+/// as yaml string.
+#[wasm_bindgen]
+pub fn write_chart_file(chart_file: Uint8Array) -> Result<Uint8Array, String> {
+    let chart_file = decode::<quary_proto::ChartFile>(chart_file)?;
+    let yaml = chart_file_to_yaml(&chart_file)?;
+    Ok(Uint8Array::from(yaml.as_bytes()))
+}
+
 /// string to chart file parses a chart file in Uint8Array string and returns a Uint8Array chart
 /// file encoded in proto.
 #[wasm_bindgen]