diff --git a/src/backend/decrypt.rs b/src/backend/decrypt.rs
index 4bf0c35..e12759f 100644
--- a/src/backend/decrypt.rs
+++ b/src/backend/decrypt.rs
@@ -1,6 +1,6 @@
 use thiserror::Error;
 
-use super::{FileType, Id, ReadBackend};
+use super::{FileType, Id, IdWithSize, ReadBackend};
 use crate::crypto::{CryptoError, Key};
 
 /// RepoError describes the errors that can be returned by accessing this repository
@@ -41,6 +41,12 @@ impl<R: ReadBackend> ReadBackend for DecryptBackend<R> {
         self.backend.list(tpe).map_err(RepoError::RepoError)
     }
 
+    fn list_with_size(&self, tpe: FileType) -> Result<Vec<IdWithSize>, Self::Error> {
+        self.backend
+            .list_with_size(tpe)
+            .map_err(RepoError::RepoError)
+    }
+
     fn read_full(&self, tpe: FileType, id: Id) -> Result<Vec<u8>, Self::Error> {
         self.key
             .decrypt_data(&self.backend.read_full(tpe, id)?)
diff --git a/src/backend/local.rs b/src/backend/local.rs
index d8d7606..9883ffc 100644
--- a/src/backend/local.rs
+++ b/src/backend/local.rs
@@ -3,7 +3,7 @@ use std::io::{Read, Seek, SeekFrom};
 use std::path::PathBuf;
 use walkdir::WalkDir;
 
-use super::{FileType, Id, ReadBackend};
+use super::{FileType, Id, IdWithSize, ReadBackend};
 
 #[derive(Clone)]
 pub struct LocalBackend {
@@ -50,6 +50,20 @@ impl ReadBackend for LocalBackend {
         Ok(walker.collect())
     }
 
+    fn list_with_size(&self, tpe: FileType) -> Result<Vec<IdWithSize>, Self::Error> {
+        let walker = WalkDir::new(self.path.join(tpe.name()))
+            .into_iter()
+            .filter_map(walkdir::Result::ok)
+            .filter(|e| e.file_type().is_file())
+            .map(|e| {
+                IdWithSize::new(
+                    Id::from_hex(&e.file_name().to_string_lossy()).unwrap(),
+                    e.metadata().unwrap().len().try_into().unwrap(),
+                )
+            });
+        Ok(walker.collect())
+    }
+
     fn read_full(&self, tpe: FileType, id: Id) -> Result<Vec<u8>, Self::Error> {
         fs::read(self.path(tpe, id))
     }
diff --git a/src/backend/mod.rs b/src/backend/mod.rs
index 81a815e..4ebd92c 100644
--- a/src/backend/mod.rs
+++ b/src/backend/mod.rs
@@ -1,11 +1,12 @@
+use crate::id::*;
+use derive_more::Constructor;
+
 pub mod decrypt;
 pub mod local;
 
 pub use decrypt::DecryptBackend;
 pub use local::LocalBackend;
 
-use crate::id::*;
-
 #[derive(Clone, Copy)]
 pub enum FileType {
     Config,
@@ -27,11 +28,18 @@ impl FileType {
     }
 }
 
+#[derive(Constructor)]
+pub struct IdWithSize {
+    id: Id,
+    size: u32,
+}
+
 pub trait ReadBackend: Clone {
     type Error: Send + Sync + std::error::Error + 'static;
 
     fn location(&self) -> &str;
     fn list(&self, tpe: FileType) -> Result<Vec<Id>, Self::Error>;
+    fn list_with_size(&self, tpe: FileType) -> Result<Vec<IdWithSize>, Self::Error>;
     fn read_full(&self, tpe: FileType, id: Id) -> Result<Vec<u8>, Self::Error>;
     fn read_partial(
         &self,