diff --git a/native/spark-expr/src/json_funcs/mod.rs b/native/spark-expr/src/json_funcs/mod.rs
new file mode 100644
index 0000000000..de3037590d
--- /dev/null
+++ b/native/spark-expr/src/json_funcs/mod.rs
@@ -0,0 +1,20 @@
+// Licensed to the Apache Software Foundation (ASF) under one
+// or more contributor license agreements.  See the NOTICE file
+// distributed with this work for additional information
+// regarding copyright ownership.  The ASF licenses this file
+// to you 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.
+
+mod to_json;
+
+pub use to_json::ToJson;
diff --git a/native/spark-expr/src/to_json.rs b/native/spark-expr/src/json_funcs/to_json.rs
similarity index 99%
rename from native/spark-expr/src/to_json.rs
rename to native/spark-expr/src/json_funcs/to_json.rs
index 91b46c6f04..3389ea3a0e 100644
--- a/native/spark-expr/src/to_json.rs
+++ b/native/spark-expr/src/json_funcs/to_json.rs
@@ -19,7 +19,7 @@
 // of the Spark-specific compatibility features that we need (including
 // being able to specify Spark-compatible cast from all types to string)
 
-use crate::cast::SparkCastOptions;
+use crate::SparkCastOptions;
 use crate::{spark_cast, EvalMode};
 use arrow_array::builder::StringBuilder;
 use arrow_array::{Array, ArrayRef, RecordBatch, StringArray, StructArray};
@@ -250,7 +250,7 @@ fn struct_to_json(array: &StructArray, timezone: &str) -> Result<ArrayRef> {
 
 #[cfg(test)]
 mod test {
-    use crate::to_json::struct_to_json;
+    use crate::json_funcs::to_json::struct_to_json;
     use arrow_array::types::Int32Type;
     use arrow_array::{Array, PrimitiveArray, StringArray};
     use arrow_array::{ArrayRef, BooleanArray, Int32Array, StructArray};
diff --git a/native/spark-expr/src/lib.rs b/native/spark-expr/src/lib.rs
index c614e1f0a2..ee58f6290d 100644
--- a/native/spark-expr/src/lib.rs
+++ b/native/spark-expr/src/lib.rs
@@ -42,9 +42,9 @@ mod struct_funcs;
 pub use negative::{create_negate_expr, NegativeExpr};
 mod normalize_nan;
 
+mod json_funcs;
 pub mod test_common;
 pub mod timezone;
-mod to_json;
 mod unbound;
 pub use unbound::UnboundColumn;
 pub mod utils;
@@ -66,10 +66,10 @@ pub use comet_scalar_funcs::create_comet_physical_fun;
 pub use datetime_funcs::*;
 pub use error::{SparkError, SparkResult};
 pub use if_expr::IfExpr;
+pub use json_funcs::ToJson;
 pub use list::{ArrayInsert, GetArrayStructFields, ListExtract};
 pub use string_funcs::*;
 pub use struct_funcs::*;
-pub use to_json::ToJson;
 
 /// Spark supports three evaluation modes when evaluating expressions, which affect
 /// the behavior when processing input values that are invalid or would result in an