diff --git a/github-release.py b/github-release.py
new file mode 100644
index 0000000..edeec44
--- /dev/null
+++ b/github-release.py
@@ -0,0 +1,173 @@
+#!/usr/bin/env python3
+import os
+import sys
+import threading
+import traceback
+import queue
+from pathlib import Path
+from datetime import datetime
+
+import requests
+
+
+BASE_URL = os.getenv("TUNASYNC_UPSTREAM_URL", "https://api.github.com/repos/")
+WORKING_DIR = os.getenv("TUNASYNC_WORKING_DIR")
+REPOS = ["googlefonts/noto-fonts",
+         "googlefonts/noto-cjk",
+         "googlefonts/noto-emoji",
+         "be5invis/Sarasa-Gothic",
+         "VSCodium/vscodium",
+         ]
+
+# connect and read timeout value
+TIMEOUT_OPTION = (7, 10)
+
+
+def requests_download(remote_url: str, dst_file: Path, remote_ts: float):
+    # NOTE the stream=True parameter below
+    with requests.get(remote_url, stream=True) as r:
+        r.raise_for_status()
+        with open(dst_file, 'wb') as f:
+            for chunk in r.iter_content(chunk_size=1024**2):
+                if chunk:  # filter out keep-alive new chunks
+                    f.write(chunk)
+                    # f.flush()
+        os.utime(dst_file, (remote_ts, remote_ts))
+
+
+def downloading_worker(q):
+    while True:
+        item = q.get()
+        if item is None:
+            break
+
+        url, dst_file, working_dir, updated = item
+
+        print("downloading", url, "to",
+              dst_file.relative_to(working_dir), flush=True)
+        try:
+            requests_download(url, dst_file, updated)
+        except Exception:
+            print("Failed to download", url, flush=True)
+            if dst_file.is_file():
+                dst_file.unlink()
+
+        q.task_done()
+
+
+def create_workers(n):
+    task_queue = queue.Queue()
+    for i in range(n):
+        t = threading.Thread(target=downloading_worker, args=(task_queue, ))
+        t.start()
+    return task_queue
+
+
+def main():
+    import argparse
+    parser = argparse.ArgumentParser()
+    parser.add_argument("--base-url", default=BASE_URL)
+    parser.add_argument("--working-dir", default=WORKING_DIR)
+    parser.add_argument("--repo", type=str, nargs='*', default=REPOS,
+                        help='repositories to download (e.g. --repo be5invis/Sarasa-Gothic googlefonts/noto-emoji)')
+    parser.add_argument("--workers", default=1, type=int,
+                        help='number of concurrent downloading jobs')
+    parser.add_argument("--fast-skip", action='store_true',
+                        help='do not verify size and timestamp of existing files')
+    args = parser.parse_args()
+
+    if args.working_dir is None:
+        raise Exception("Working Directory is None")
+
+    working_dir = Path(args.working_dir)
+    task_queue = create_workers(args.workers)
+    remote_filelist = []
+    cleaning = False
+
+    for repo in args.repo:
+        repo_local = working_dir / Path(repo)
+        print(f"syncing {repo} to {repo_local}")
+        try:
+            r = requests.get(f"{args.base_url}{repo}/releases")
+            r.raise_for_status()
+            releases = r.json()
+        except:
+            traceback.print_exc()
+            break
+
+        for latest in releases:
+            if not latest['draft'] and not latest['prerelease']:
+                break
+        else:
+            print("Error: No release version found")
+            continue
+
+        name = latest['name'] or latest['tag_name']
+        if len(name) == 0:
+            print("Error: Unnamed release")
+            continue
+
+        if len(latest['assets']) == 0:
+            url = latest['tarball_url']
+            updated = datetime.strptime(latest['published_at'], '%Y-%m-%dT%H:%M:%SZ').timestamp()
+            dst_file = repo_local / name / 'repo-snapshot.tar.gz'
+            remote_filelist.append(dst_file.relative_to(working_dir))
+
+            if dst_file.is_file():
+                print("skipping", dst_file.relative_to(working_dir), flush=True)
+            else:
+                dst_file.parent.mkdir(parents=True, exist_ok=True)
+                task_queue.put((url, dst_file, working_dir, updated))
+
+        for asset in latest['assets']:
+            if '/' in asset['name'] or '\\' in asset['name']:
+                print(f"Error: Invalid file name {asset['name']}")
+                continue
+            url = asset['browser_download_url']
+            updated = datetime.strptime(asset['updated_at'], '%Y-%m-%dT%H:%M:%SZ').timestamp()
+            dst_file = repo_local / name / asset['name']
+            remote_filelist.append(dst_file.relative_to(working_dir))
+
+            if dst_file.is_file():
+                if args.fast_skip:
+                    print("fast skipping", dst_file.relative_to(working_dir), flush=True)
+                    continue
+                else:
+                    stat = dst_file.stat()
+                    local_filesize = stat.st_size
+                    local_mtime = stat.st_mtime
+                    # print(f"{local_filesize} vs {asset['size']}")
+                    # print(f"{local_mtime} vs {updated}")
+                    if asset['size'] == local_filesize and local_mtime == updated:
+                        print("skipping", dst_file.relative_to(working_dir), flush=True)
+                        continue
+            else:
+                dst_file.parent.mkdir(parents=True, exist_ok=True)
+
+            task_queue.put((url, dst_file, working_dir, updated))
+    else:
+        cleaning = True
+
+    # block until all tasks are done
+    task_queue.join()
+    # stop workers
+    for i in range(args.workers):
+        task_queue.put(None)
+
+    if cleaning:
+        local_filelist = []
+        for local_file in working_dir.glob('**/*'):
+            if local_file.is_file():
+                local_filelist.append(local_file.relative_to(working_dir))
+
+        for old_file in set(local_filelist) - set(remote_filelist):
+            print("deleting", old_file, flush=True)
+            old_file = working_dir / old_file
+            old_file.unlink()
+
+
+if __name__ == "__main__":
+    main()
+
+
+# vim: ts=4 sw=4 sts=4 expandtab