diff --git a/.forgejo/actions/nixos-docker/Dockerfile b/.forgejo/actions/nixos-docker/Dockerfile
index 1d309553..7ac14dc7 100644
--- a/.forgejo/actions/nixos-docker/Dockerfile
+++ b/.forgejo/actions/nixos-docker/Dockerfile
@@ -1,4 +1,2 @@
 FROM nixos/nix
-ENV TZ="Asia/Tokyo"
-RUN nix-channel --update
 ENTRYPOINT [ "/root/.nix-profile/bin/sleep", "100000" ]
\ No newline at end of file