diff --git a/src/main.rs b/src/main.rs
index 5305eb7..ba85475 100644
--- a/src/main.rs
+++ b/src/main.rs
@@ -530,10 +530,10 @@ fn mode_diff(cmd: &mut Command, args: Args, ids: &mut Vec<i64>, tags: &mut Vec<S
                 .spawn()
                 .expect("Failed to execute diff command");
 
-            let stdout_a = unsafe { std::fs::File::from_raw_fd(fd_a_write) };
-            let stdout_b = unsafe { std::fs::File::from_raw_fd(fd_b_write) };
-            let stdout_a = BufWriter::new(stdout_a);
-            let stdout_b = BufWriter::new(stdout_b);
+            let mut stdout_a = unsafe { std::fs::File::from_raw_fd(fd_a_write) };
+            let mut stdout_b = unsafe { std::fs::File::from_raw_fd(fd_b_write) };
+            let mut stdout_a = BufWriter::new(stdout_a);
+            let mut stdout_b = BufWriter::new(stdout_b);
 
             compression_engine_a.copy(item_path_a.clone(), &mut stdout_a)?;
             compression_engine_b.copy(item_path_b.clone(), &mut stdout_b)?;