diff --git a/nix/docker/default.nix b/nix/docker/default.nix
index 6a5e92832..45fde74de 100644
--- a/nix/docker/default.nix
+++ b/nix/docker/default.nix
@@ -37,7 +37,7 @@ let
       mkdir -p /var/lib
 
       groupadd -r uniworx
-      useradd -r -g uniworx -d /var/lib/uniworx -M uniworx
+      useradd -r -g uniworx -d /var/lib/uniworx -M uniworx --uid 999
       install -d -g uniworx -o uniworx -m 0750 /var/lib/uniworx
 
       mkdir -p /var/log