diff --git a/Worker.dockerfile b/Worker.dockerfile
index 123ab05..ff11184 100644
--- a/Worker.dockerfile
+++ b/Worker.dockerfile
@@ -77,11 +77,15 @@ RUN apk -U upgrade \
         curl \
  && adduser -g ${GID} -u ${UID} --disabled-password --gecos "" synapse \
  && rm -rf /var/cache/apk/*
+ 
+ # ensure www-data user exists
+RUN set -x \
+	&& addgroup -g 82 -S www-data \
+	&& adduser -u 82 -D -S -G www-data www-data
 
 RUN pip install --upgrade pip \
  && pip install -e "git+https://github.com/matrix-org/mjolnir.git#egg=mjolnir&subdirectory=synapse_antispam"
 
-
 RUN mkdir /var/log/nginx /var/lib/nginx
 
 COPY --from=deps_base /usr/sbin/nginx /usr/sbin