diff --git a/Cargo.lock b/Cargo.lock
index 7445bcb..4310d61 100644
--- a/Cargo.lock
+++ b/Cargo.lock
@@ -1195,6 +1195,7 @@ dependencies = [
  "prometheus",
  "regex",
  "reqwest",
+ "serde",
  "serde_json",
  "stderrlog",
  "structopt",
diff --git a/Cargo.toml b/Cargo.toml
index 8840465..24e09db 100644
--- a/Cargo.toml
+++ b/Cargo.toml
@@ -20,6 +20,7 @@ stderrlog = "0.4.3"
 structopt = "0.3.9"
 yup-oauth2 = "^3.1"
 warp = "0.1"
+serde = { version = "1.0.104", features = ["derive"] }
 
 [dependencies.prometheus]
 features = ["process"]
diff --git a/src/library.rs b/src/library.rs
new file mode 100644
index 0000000..d7a3ebf
--- /dev/null
+++ b/src/library.rs
@@ -0,0 +1,84 @@
+use std::fs;
+use std::fs::File;
+use std::io;
+use std::path::Path;
+use std::path::PathBuf;
+
+use google_photoslibrary1 as photos;
+use log::info;
+use photos::schemas::Album;
+use photos::schemas::MediaItem;
+
+pub struct Library {
+    root: PathBuf,
+    originals_dir: PathBuf,
+}
+
+impl Library {
+    pub fn new(root: PathBuf) -> io::Result<Library> {
+        let lib = Library {
+            originals_dir: root.join("images").join("originals"),
+            root,
+        };
+        if !lib.originals_dir.exists() {
+            info!(
+                "create originals dir {}",
+                &lib.originals_dir.to_string_lossy()
+            );
+            fs::create_dir_all(&lib.originals_dir)?;
+        }
+        Ok(lib)
+    }
+    pub fn create_album_index(&self, albums: &Vec<Album>) -> io::Result<()> {
+        // Serialize it to a JSON string.
+        let j = serde_json::to_string(albums)?;
+
+        let path = self.root.join("albums.json");
+        info!("saving {}", path.to_string_lossy());
+        fs::write(path, j)
+    }
+    pub fn create_album<P: AsRef<Path>>(
+        &self,
+        album_id: P,
+        media_items: &Vec<MediaItem>,
+    ) -> io::Result<()> {
+        let album_dir = self.root.join(album_id);
+        if !album_dir.exists() {
+            info!("making album directory {}", album_dir.to_string_lossy());
+            fs::create_dir_all(&album_dir)?;
+        }
+        let j = serde_json::to_string(&media_items)?;
+        let path = album_dir.join("album.json");
+        info!("saving {}", path.to_string_lossy());
+        fs::write(path, j)
+    }
+    pub fn download_image(
+        &self,
+        filename: &str,
+        media_items_id: &str,
+        base_url: &str,
+    ) -> Result<PathBuf, Box<dyn std::error::Error>> {
+        // Put images from all albums in common directory.
+        let image_path = self.originals_dir.join(media_items_id);
+        if image_path.exists() {
+            info!(
+                "Skipping already downloaded {} @ {}",
+                &filename,
+                image_path.to_string_lossy()
+            );
+        } else {
+            let download_path = image_path.with_extension("download");
+            let url = format!("{}=d", base_url);
+            let mut r = reqwest::blocking::get(&url)?;
+            let mut w = File::create(&download_path)?;
+            let _n = io::copy(&mut r, &mut w)?;
+            info!(
+                "Rename {} -> {}",
+                download_path.to_string_lossy(),
+                image_path.to_string_lossy()
+            );
+            fs::rename(download_path, &image_path)?;
+        }
+        Ok(image_path)
+    }
+}
diff --git a/src/main.rs b/src/main.rs
index 205afb3..7ae6fd7 100644
--- a/src/main.rs
+++ b/src/main.rs
@@ -17,6 +17,7 @@ use reqwest;
 use structopt::StructOpt;
 use yup_oauth2::{Authenticator, InstalledFlow};
 
+mod library;
 mod web;
 
 #[derive(Debug, StructOpt)]
@@ -198,67 +199,30 @@ fn sync_albums(
     title_filter: Option<Regex>,
     output_dir: PathBuf,
 ) -> Result<(), Box<dyn Error>> {
-    // Put images from all albums in common directory.
-    let image_dir = output_dir.join("images");
-    if !image_dir.exists() {
-        fs::create_dir_all(&image_dir)?;
-    }
+    let lib = library::Library::new(output_dir)?;
     let albums = list_albums(client, title_filter)?;
+    lib.create_album_index(&albums)?;
     for a in &albums {
         let album_id = a.id.as_ref().expect("unset album id").to_string();
-        let album_dir = output_dir.join(&album_id);
-        if !album_dir.exists() {
-            info!("making album directory {}", album_dir.to_string_lossy());
-            fs::create_dir_all(&album_dir)?;
-        }
-
-        let album = search_media_items(client, &album_id)?;
-        for (i, mi) in album.iter().enumerate() {
+        let media_items = search_media_items(client, &album_id)?;
+        lib.create_album(&album_id, &media_items)?;
+        for (i, mi) in media_items.iter().enumerate() {
             let mi_id = mi.id.as_ref().expect("unset media item id").to_string();
             let filename = mi
                 .filename
                 .as_ref()
                 .map_or("NO_FILENAME".to_string(), |s| s.to_string());
-            let image_path = image_dir.join(mi_id);
-            if image_path.exists() {
-                info!(
-                    "Skipping already downloaded {} @ {}",
-                    &filename,
-                    image_path.to_string_lossy()
-                );
-            } else {
-                let download_path = image_path.with_extension("download");
-                info!(
-                    "({}/{}) Downloading {} -> {}",
-                    i + 1,
-                    &album.len(),
-                    &filename,
-                    download_path.to_string_lossy()
-                );
-                let base_url = mi.base_url.as_ref().expect("missing base_url");
-                let url = format!("{}=d", base_url);
-                let mut r = reqwest::blocking::get(&url)?;
-                let mut w = File::create(&download_path)?;
-                let _n = io::copy(&mut r, &mut w)?;
-                info!(
-                    "Rename {} -> {}",
-                    download_path.to_string_lossy(),
-                    image_path.to_string_lossy()
-                );
-                fs::rename(download_path, &image_path)?;
-            }
+            let base_url = mi.base_url.as_ref().expect("missing base_url");
+            let image_path = lib.download_image(&filename, &mi_id, &base_url)?;
+            info!(
+                "({}/{}) Downloading {} -> {}",
+                i + 1,
+                &media_items.len(),
+                &filename,
+                image_path.to_string_lossy()
+            );
         }
-        let j = serde_json::to_string(&album)?;
-        let path = album_dir.join("album.json");
-        info!("saving {}", path.to_string_lossy());
-        fs::write(path, j)?;
     }
-    // Serialize it to a JSON string.
-    let j = serde_json::to_string(&albums)?;
-
-    let path = output_dir.join("albums.json");
-    info!("saving {}", path.to_string_lossy());
-    fs::write(path, j)?;
     Ok(())
 }