diff --git a/crates/librqbit/src/session.rs b/crates/librqbit/src/session.rs
index 2d38ccf..97f927a 100644
--- a/crates/librqbit/src/session.rs
+++ b/crates/librqbit/src/session.rs
@@ -16,10 +16,7 @@ use crate::{
     peer_connection::PeerConnectionOptions,
     read_buf::ReadBuf,
     spawn_utils::BlockingSpawner,
-    storage::{
-        filesystem::{FilesystemStorageFactory, MmapFilesystemStorageFactory},
-        BoxStorageFactory, StorageFactoryExt,
-    },
+    storage::{filesystem::FilesystemStorageFactory, BoxStorageFactory, StorageFactoryExt},
     torrent_state::{
         ManagedTorrentBuilder, ManagedTorrentHandle, ManagedTorrentState, TorrentStateLive,
     },
@@ -193,7 +190,7 @@ pub struct Session {
 
     default_defer_writes: bool,
 
-    // default_storage_factory: Option<BoxStorageFactory>,
+    default_storage_factory: Option<BoxStorageFactory>,
 
     // This is stored for all tasks to stop when session is dropped.
     _cancellation_token_drop_guard: DropGuard,
@@ -430,7 +427,8 @@ pub struct SessionOptions {
     // If true, will write to disk in separate threads. The downside is additional allocations.
     // May be useful if the disk is slow.
     pub default_defer_writes: bool,
-    // pub default_storage_factory: Option<BoxStorageFactory>,
+
+    pub default_storage_factory: Option<BoxStorageFactory>,
 }
 
 async fn create_tcp_listener(
@@ -530,6 +528,7 @@ impl Session {
                 cancellation_token: token,
                 tcp_listen_port,
                 default_defer_writes: opts.default_defer_writes,
+                default_storage_factory: opts.default_storage_factory,
             });
 
             if let Some(tcp_listener) = tcp_listener {
@@ -1023,9 +1022,8 @@ impl Session {
         let storage_factory = opts
             .storage_factory
             .take()
-            // .unwrap_or_else(|| self.default_storage_factory.clone())
-            // .unwrap_or_else(|| FilesystemStorageFactory::default().boxed());
-            .unwrap_or_else(|| MmapFilesystemStorageFactory::default().boxed());
+            .or_else(|| self.default_storage_factory.as_ref().map(|f| f.clone_box()))
+            .unwrap_or_else(|| FilesystemStorageFactory::default().boxed());
 
         if opts.list_only {
             return Ok(AddTorrentResponse::ListOnly(ListOnlyResponse {
diff --git a/crates/librqbit/src/storage/examples/inmemory.rs b/crates/librqbit/src/storage/examples/inmemory.rs
index 38a279f..d725995 100644
--- a/crates/librqbit/src/storage/examples/inmemory.rs
+++ b/crates/librqbit/src/storage/examples/inmemory.rs
@@ -6,7 +6,7 @@ use parking_lot::RwLock;
 
 use crate::type_aliases::FileInfos;
 
-use crate::storage::{StorageFactory, TorrentStorage};
+use crate::storage::{StorageFactory, StorageFactoryExt, TorrentStorage};
 
 struct InMemoryPiece {
     bytes: Box<[u8]>,
@@ -19,7 +19,7 @@ impl InMemoryPiece {
     }
 }
 
-#[derive(Default)]
+#[derive(Default, Clone)]
 pub struct InMemoryExampleStorageFactory {}
 
 impl StorageFactory for InMemoryExampleStorageFactory {
@@ -31,6 +31,10 @@ impl StorageFactory for InMemoryExampleStorageFactory {
     ) -> anyhow::Result<InMemoryExampleStorage> {
         InMemoryExampleStorage::new(info.lengths, info.file_infos.clone())
     }
+
+    fn clone_box(&self) -> crate::storage::BoxStorageFactory {
+        self.clone().boxed()
+    }
 }
 
 pub struct InMemoryExampleStorage {
diff --git a/crates/librqbit/src/storage/examples/mmap.rs b/crates/librqbit/src/storage/examples/mmap.rs
index 290cef7..5f40a1c 100644
--- a/crates/librqbit/src/storage/examples/mmap.rs
+++ b/crates/librqbit/src/storage/examples/mmap.rs
@@ -3,11 +3,11 @@ use memmap2::{MmapMut, MmapOptions};
 use parking_lot::RwLock;
 
 use crate::{
-    storage::{StorageFactory, TorrentStorage},
+    storage::{StorageFactory, StorageFactoryExt, TorrentStorage},
     FileInfos, ManagedTorrentInfo,
 };
 
-#[derive(Default)]
+#[derive(Default, Clone)]
 pub struct MmapStorageFactory {}
 
 pub struct MmapStorage {
@@ -28,6 +28,10 @@ impl StorageFactory for MmapStorageFactory {
             file_infos: info.file_infos.clone(),
         })
     }
+
+    fn clone_box(&self) -> crate::storage::BoxStorageFactory {
+        self.clone().boxed()
+    }
 }
 
 impl TorrentStorage for MmapStorage {
diff --git a/crates/librqbit/src/storage/filesystem/fs.rs b/crates/librqbit/src/storage/filesystem/fs.rs
index dd63448..36e57ab 100644
--- a/crates/librqbit/src/storage/filesystem/fs.rs
+++ b/crates/librqbit/src/storage/filesystem/fs.rs
@@ -6,13 +6,13 @@ use std::{
 
 use anyhow::Context;
 
-use crate::torrent_state::ManagedTorrentInfo;
+use crate::{storage::StorageFactoryExt, torrent_state::ManagedTorrentInfo};
 
 use crate::storage::{StorageFactory, TorrentStorage};
 
 use super::opened_file::OpenedFile;
 
-#[derive(Default)]
+#[derive(Default, Clone, Copy)]
 pub struct FilesystemStorageFactory {}
 
 impl StorageFactory for FilesystemStorageFactory {
@@ -59,6 +59,10 @@ impl StorageFactory for FilesystemStorageFactory {
             opened_files: files,
         })
     }
+
+    fn clone_box(&self) -> crate::storage::BoxStorageFactory {
+        self.boxed()
+    }
 }
 
 pub struct FilesystemStorage {
diff --git a/crates/librqbit/src/storage/filesystem/mmap.rs b/crates/librqbit/src/storage/filesystem/mmap.rs
index 87dc044..731db70 100644
--- a/crates/librqbit/src/storage/filesystem/mmap.rs
+++ b/crates/librqbit/src/storage/filesystem/mmap.rs
@@ -6,11 +6,11 @@ use parking_lot::RwLock;
 
 use crate::torrent_state::ManagedTorrentInfo;
 
-use crate::storage::{StorageFactory, TorrentStorage};
+use crate::storage::{StorageFactory, StorageFactoryExt, TorrentStorage};
 
 use super::{FilesystemStorage, FilesystemStorageFactory};
 
-#[derive(Default)]
+#[derive(Default, Clone, Copy)]
 pub struct MmapFilesystemStorageFactory {}
 
 type OpenedMmap = RwLock<MmapMut>;
@@ -36,6 +36,10 @@ impl StorageFactory for MmapFilesystemStorageFactory {
             fs: fs_storage,
         })
     }
+
+    fn clone_box(&self) -> crate::storage::BoxStorageFactory {
+        self.boxed()
+    }
 }
 
 pub struct MmapFilesystemStorage {
diff --git a/crates/librqbit/src/storage/middleware/slow.rs b/crates/librqbit/src/storage/middleware/slow.rs
index 4e42ba2..d588574 100644
--- a/crates/librqbit/src/storage/middleware/slow.rs
+++ b/crates/librqbit/src/storage/middleware/slow.rs
@@ -2,8 +2,9 @@ use std::time::Duration;
 
 use rand_distr::Distribution;
 
-use crate::storage::{StorageFactory, TorrentStorage};
+use crate::storage::{StorageFactory, StorageFactoryExt, TorrentStorage};
 
+#[derive(Clone)]
 pub struct SlowStorageFactory<U> {
     underlying_factory: U,
 }
@@ -16,7 +17,7 @@ impl<U: StorageFactory> SlowStorageFactory<U> {
     }
 }
 
-impl<U: StorageFactory> StorageFactory for SlowStorageFactory<U> {
+impl<U: StorageFactory + Clone> StorageFactory for SlowStorageFactory<U> {
     type Storage = SlowStorage<U::Storage>;
 
     fn init_storage(&self, info: &crate::ManagedTorrentInfo) -> anyhow::Result<Self::Storage> {
@@ -28,6 +29,10 @@ impl<U: StorageFactory> StorageFactory for SlowStorageFactory<U> {
     fn is_type_id(&self, type_id: std::any::TypeId) -> bool {
         self.underlying_factory.is_type_id(type_id)
     }
+
+    fn clone_box(&self) -> crate::storage::BoxStorageFactory {
+        self.clone().boxed()
+    }
 }
 
 pub struct SlowStorage<U> {
diff --git a/crates/librqbit/src/storage/middleware/timing.rs b/crates/librqbit/src/storage/middleware/timing.rs
index 9d3210b..9012384 100644
--- a/crates/librqbit/src/storage/middleware/timing.rs
+++ b/crates/librqbit/src/storage/middleware/timing.rs
@@ -1,5 +1,6 @@
-use crate::storage::{StorageFactory, TorrentStorage};
+use crate::storage::{StorageFactory, StorageFactoryExt, TorrentStorage};
 
+#[derive(Clone)]
 pub struct TimingStorageFactory<U> {
     name: String,
     underlying_factory: U,
@@ -14,7 +15,7 @@ impl<U> TimingStorageFactory<U> {
     }
 }
 
-impl<U: StorageFactory> StorageFactory for TimingStorageFactory<U> {
+impl<U: StorageFactory + Clone> StorageFactory for TimingStorageFactory<U> {
     type Storage = TimingStorage<U::Storage>;
 
     fn init_storage(&self, info: &crate::ManagedTorrentInfo) -> anyhow::Result<Self::Storage> {
@@ -27,6 +28,10 @@ impl<U: StorageFactory> StorageFactory for TimingStorageFactory<U> {
     fn is_type_id(&self, type_id: std::any::TypeId) -> bool {
         self.underlying_factory.is_type_id(type_id)
     }
+
+    fn clone_box(&self) -> crate::storage::BoxStorageFactory {
+        self.clone().boxed()
+    }
 }
 
 pub struct TimingStorage<U> {
diff --git a/crates/librqbit/src/storage/mod.rs b/crates/librqbit/src/storage/mod.rs
index 063d280..33c89f3 100644
--- a/crates/librqbit/src/storage/mod.rs
+++ b/crates/librqbit/src/storage/mod.rs
@@ -16,6 +16,7 @@ pub trait StorageFactory: Send + Sync + Any {
     fn is_type_id(&self, type_id: TypeId) -> bool {
         Self::type_id(self) == type_id
     }
+    fn clone_box(&self) -> BoxStorageFactory;
 }
 
 pub type BoxStorageFactory = Box<dyn StorageFactory<Storage = Box<dyn TorrentStorage>>>;
@@ -41,6 +42,10 @@ impl<SF: StorageFactory> StorageFactoryExt for SF {
             fn is_type_id(&self, type_id: TypeId) -> bool {
                 self.sf.type_id() == type_id
             }
+
+            fn clone_box(&self) -> BoxStorageFactory {
+                self.sf.clone_box()
+            }
         }
 
         Box::new(Wrapper { sf: self })
@@ -53,6 +58,10 @@ impl<U: StorageFactory + ?Sized> StorageFactory for Box<U> {
     fn init_storage(&self, info: &ManagedTorrentInfo) -> anyhow::Result<U::Storage> {
         (**self).init_storage(info)
     }
+
+    fn clone_box(&self) -> BoxStorageFactory {
+        (**self).clone_box()
+    }
 }
 
 pub trait TorrentStorage: Send + Sync {
diff --git a/crates/librqbit/src/tests/e2e.rs b/crates/librqbit/src/tests/e2e.rs
index 86f615b..d994a78 100644
--- a/crates/librqbit/src/tests/e2e.rs
+++ b/crates/librqbit/src/tests/e2e.rs
@@ -73,6 +73,7 @@ async fn test_e2e() {
                         listen_port_range: Some(15100..17000),
                         enable_upnp_port_forwarding: false,
                         default_defer_writes: false,
+                        default_storage_factory: None,
                     },
                 )
                 .await
diff --git a/crates/rqbit/src/main.rs b/crates/rqbit/src/main.rs
index 28471ff..ce1719a 100644
--- a/crates/rqbit/src/main.rs
+++ b/crates/rqbit/src/main.rs
@@ -297,6 +297,13 @@ async fn async_main(opts: Opts) -> anyhow::Result<()> {
         },
         enable_upnp_port_forwarding: !opts.disable_upnp,
         default_defer_writes: opts.defer_writes,
+        default_storage_factory: Some({
+            if opts.experimental_mmap_storage {
+                MmapFilesystemStorageFactory::default().boxed()
+            } else {
+                FilesystemStorageFactory::default().boxed()
+            }
+        }),
     };
 
     let stats_printer = |session: Arc<Session>| async move {