diff --git a/src/application.cpp b/src/application.cpp
index 258c9ad..df62fb3 100644
--- a/src/application.cpp
+++ b/src/application.cpp
@@ -570,11 +570,11 @@ void GitApp::tag_archive(std::string name, std::string tag_name) {
     }
 
     const std::string base =
-        util::sanitize_filename(name) + "_" + util::sanitize_filename(tag_name);
+        util::sanitize_filename(name) + "-" + util::sanitize_filename(tag_name);
     const std::string download_name = base + ".tar.gz";
     // The commit oid is part of the cache key so a moved tag never serves stale
     // contents.
-    const std::string cache_file = cache_root_ + "/" + base + "_" + oid + ".tar.gz";
+    const std::string cache_file = cache_root_ + "/" + base + "-" + oid + ".tar.gz";
 
     std::error_code ec;
     std::filesystem::create_directories(cache_root_, ec);