diff --git a/src/backup/manifest.rs b/src/backup/manifest.rs
index 8742cb0a..d9a55655 100644
--- a/src/backup/manifest.rs
+++ b/src/backup/manifest.rs
@@ -149,49 +149,7 @@ impl BackupManifest {
 
     // Generate canonical json
     fn to_canonical_json(value: &Value) -> Result<Vec<u8>, Error> {
-        let mut data = Vec::new();
-        Self::write_canonical_json(value, &mut data)?;
-        Ok(data)
-    }
-
-    fn write_canonical_json(value: &Value, output: &mut Vec<u8>) -> Result<(), Error> {
-        match value {
-            Value::Null => bail!("got unexpected null value"),
-            Value::String(_) | Value::Number(_) | Value::Bool(_) => {
-                serde_json::to_writer(output, &value)?;
-            }
-            Value::Array(list) => {
-                output.push(b'[');
-                let mut iter = list.iter();
-                if let Some(item) = iter.next() {
-                    Self::write_canonical_json(item, output)?;
-                    for item in iter {
-                        output.push(b',');
-                        Self::write_canonical_json(item, output)?;
-                    }
-                }
-                output.push(b']');
-              }
-            Value::Object(map) => {
-                output.push(b'{');
-                let mut keys: Vec<&str> = map.keys().map(String::as_str).collect();
-                keys.sort();
-                let mut iter = keys.into_iter();
-                if let Some(key) = iter.next() {
-                    serde_json::to_writer(&mut *output, &key)?;
-                    output.push(b':');
-                    Self::write_canonical_json(&map[key], output)?;
-                    for key in iter {
-                        output.push(b',');
-                        serde_json::to_writer(&mut *output, &key)?;
-                        output.push(b':');
-                        Self::write_canonical_json(&map[key], output)?;
-                    }
-                }
-                output.push(b'}');
-            }
-        }
-        Ok(())
+        crate::tools::json::to_canonical_json(value)
     }
 
     /// Compute manifest signature