diff --git a/src/store/mod.rs b/src/store/mod.rs
index 1f664f2..5a673ab 100644
--- a/src/store/mod.rs
+++ b/src/store/mod.rs
@@ -6,6 +6,7 @@ use std::collections::HashMap;
 use std::fs::{File, OpenOptions};
 use std::io::{Read, Write};
 use std::path::{Path, PathBuf};
+use std::collections::BTreeMap;
 
 pub mod form;
 pub mod model;
@@ -35,7 +36,7 @@ struct RepositoryConfig {
 #[derive(Serialize, Deserialize, Debug)]
 pub struct Cards {
     #[serde(default)]
-    pub cards: IndexMap<usize, Value>,
+    pub cards: BTreeMap<usize, Value>,
     #[serde(default)]
     pub counter: usize,
 }