diff --git a/ext_http_server.py b/ext_http_server.py
index 58d1cdb..1545207 100644
--- a/ext_http_server.py
+++ b/ext_http_server.py
@@ -259,6 +259,10 @@ def __init__(
 class MyServer(socketserver.ThreadingMixIn, SecureHTTPServer):
     """A threaded SecureHTTPServer with basic error filtering."""
 
+    # Run connection threads as daemons so a lingering HTTP/1.1 keep-alive
+    # connection cannot block interpreter shutdown on Ctrl-C (see issue #1).
+    daemon_threads = True
+
     def handle_error(self, request: socket | tuple[bytes, socket], client_address: Any) -> None:  # noqa: ANN401
         """Disable tracebacks on connection close errors."""
         _, exc_value, _ = sys.exc_info()
@@ -317,6 +321,8 @@ def main() -> int:
         server.serve_forever()
     except KeyboardInterrupt:
         print("\nGoodbye")
+    finally:
+        server.server_close()
     return 0
 
 
diff --git a/tests/test_ext_http_server.py b/tests/test_ext_http_server.py
index f5b0599..1cbee40 100644
--- a/tests/test_ext_http_server.py
+++ b/tests/test_ext_http_server.py
@@ -156,6 +156,12 @@ def test_server_serves_range_request(secure_server):
     assert body == b"56789ABCDEFGHIJ"
 
 
+def test_server_uses_daemon_threads():
+    # Daemon connection threads keep lingering keep-alive connections from
+    # blocking interpreter shutdown on Ctrl-C (see issue #1).
+    assert MyServer.daemon_threads is True
+
+
 def test_set_rate_limit_computes_block_size():
     RateLimitWriter.set_rate_limit(128)
     assert RateLimitWriter.block_size == int(1024 * 128 * RateLimitWriter.INTERVAL_LEN)