diff --git a/Cargo.toml b/Cargo.toml
index 705aec75..e097734e 100644
--- a/Cargo.toml
+++ b/Cargo.toml
@@ -1,6 +1,6 @@
 [package]
 name = "peroxide"
-version = "0.34.3"
+version = "0.34.4"
 authors = ["axect <axect@outlook.kr>"]
 edition = "2018"
 description = "Rust comprehensive scientific computation library contains linear algebra, numerical analysis, statistics and machine learning tools with farmiliar syntax"
diff --git a/RELEASES.md b/RELEASES.md
index 1dfddfa1..69aa4977 100644
--- a/RELEASES.md
+++ b/RELEASES.md
@@ -1,3 +1,8 @@
+# Release 0.34.4 (2024-01-28)
+
+* Derive `Serialize` and `Deserialize` for `Matrix`
+* Remove explicit implementation for `Default` for `Shape`
+
 # Release 0.34.3 (2023-11-25)
 
 * Update `peroxide-num` to `v0.1.4`
diff --git a/src/structure/matrix.rs b/src/structure/matrix.rs
index 091df7fe..baf7bbdd 100644
--- a/src/structure/matrix.rs
+++ b/src/structure/matrix.rs
@@ -607,13 +607,13 @@
 #[cfg(feature="csv")]
 extern crate csv;
 
+#[cfg(feature="csv")]
+use self::csv::{ReaderBuilder, StringRecord, WriterBuilder};
+
 #[cfg(feature = "O3")]
 extern crate blas;
 #[cfg(feature = "O3")]
 extern crate lapack;
-
-#[cfg(feature="csv")]
-use self::csv::{ReaderBuilder, StringRecord, WriterBuilder};
 use ::matrixmultiply;
 #[cfg(feature = "O3")]
 use blas::{daxpy, dgemm, dgemv};
@@ -622,6 +622,9 @@ use lapack::{dgecon, dgeqrf, dgetrf, dgetri, dgetrs, dorgqr, dgesvd, dpotrf};
 #[cfg(feature = "O3")]
 use std::f64::NAN;
 
+#[cfg(feature = "serde")]
+use serde::{Deserialize, Serialize};
+
 pub use self::Shape::{Col, Row};
 use crate::numerical::eigen::{eigen, EigenMethod};
 use crate::traits::{
@@ -661,8 +664,10 @@ pub type Perms = Vec<(usize, usize)>;
 /// println!("{}", a); // Similar to [[1,2],[3,4]]
 /// println!("{}", b); // Similar to [[1,3],[2,4]]
 /// ```
-#[derive(Debug, PartialEq, Clone, Copy)]
+#[derive(Default, Debug, PartialEq, Clone, Copy)]
+#[cfg_attr(feature = "serde", derive(Serialize, Deserialize))]
 pub enum Shape {
+    #[default]
     Col,
     Row,
 }
@@ -678,12 +683,6 @@ impl fmt::Display for Shape {
     }
 }
 
-impl Default for Shape {
-    fn default() -> Self {
-        Shape::Col
-    }
-}
-
 /// R-like matrix structure
 ///
 /// # Examples
@@ -700,6 +699,7 @@ impl Default for Shape {
 /// }; // [[1,2],[3,4]]
 /// ```
 #[derive(Debug, Clone, Default)]
+#[cfg_attr(feature = "serde", derive(Serialize, Deserialize))]
 pub struct Matrix {
     pub data: Vec<f64>,
     pub row: usize,