diff --git a/src/lib.rs b/src/lib.rs
index 50e5853..c7f4430 100644
--- a/src/lib.rs
+++ b/src/lib.rs
@@ -2,9 +2,13 @@ use bdk::Wallet;
 use bdk::database::MemoryDatabase;
 use bdk::bitcoin::Network;
 // use crate::error::FfiError;
-use std::sync::RwLock;
+use std::sync::{RwLock, Mutex};
 use std::vec::Vec;
 
+use bdk::database::BatchDatabase;
+use bdk::sled;
+use bdk::sled::Tree;
+
 //mod error;
 //mod types;
 //mod wallet;
@@ -12,21 +16,24 @@ use std::vec::Vec;
 uniffi_macros::include_scaffolding!("bdk");
 
 struct OfflineWallet {
-    wallet: Wallet<(), MemoryDatabase>,
+    wallet: Mutex<Wallet<(), Tree>>,
     //wallet: RwLock<Vec<String>>
 }
 
 impl OfflineWallet {
     fn new(descriptor: String) -> Self {
+        let database = sled::open("testdb").unwrap();
+        let tree = database.open_tree("test").unwrap();
+
         let wallet = Wallet::new_offline(
             &descriptor,
             None,
             Network::Regtest,
-            MemoryDatabase::new(),
+            tree,
         ).unwrap();
 
         OfflineWallet {
-            wallet
+            wallet: Mutex::new(wallet)
         }
 
 //        OfflineWallet {
@@ -35,3 +42,6 @@ impl OfflineWallet {
     }
 }
 
+uniffi::deps::static_assertions::assert_impl_all!(OfflineWallet: Sync, Send);
+
+