diff --git a/Jenkinsfile b/Jenkinsfile
index 8a54133..5fc2a0b 100644
--- a/Jenkinsfile
+++ b/Jenkinsfile
@@ -5,7 +5,7 @@ pipeline {
         maintainer_credential_ref = 'dockerhub-tier'
         imagename = 'g'
         tag = 'l'
-        version='3.3.4'
+        version='4.0.0-rc1'
     }
     stages {
         stage('Setting build context') {
diff --git a/comanage-registry-base/Dockerfile b/comanage-registry-base/Dockerfile
index c8c61fb..f14a6aa 100644
--- a/comanage-registry-base/Dockerfile
+++ b/comanage-registry-base/Dockerfile
@@ -16,7 +16,7 @@
 # WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
 # See the License for the specific language governing permissions and
 # limitations under the License.
-FROM php:7.3.28-apache-buster
+FROM php:7.3.30-apache-bullseye
 
 # Official PHP image with Apache HTTPD includes
 # --with-openssl
@@ -26,7 +26,7 @@ FROM php:7.3.28-apache-buster
 RUN apt-get update && apt-get install -y \
          libldap-2.4-2 \
          libldap2-dev \
-         libmariadbclient-dev \
+         libmariadb-dev \
          libpq-dev \
          libxml2 \
          libxslt1-dev \
diff --git a/comanage-registry-internet2-tier-base/Dockerfile b/comanage-registry-internet2-tier-base/Dockerfile
index bb931c3..27267ab 100644
--- a/comanage-registry-internet2-tier-base/Dockerfile
+++ b/comanage-registry-internet2-tier-base/Dockerfile
@@ -20,7 +20,7 @@ FROM centos/python-38-centos7 AS php-build
 
 USER root
 
-ARG PHP_VERSION=7.3.28
+ARG PHP_VERSION=7.3.30
 ARG PHP_SRC_URL=https://github.com/php/php-src/archive/php-${PHP_VERSION}.tar.gz
 
 RUN yum -y install epel-release \
diff --git a/comanage-registry-internet2-tier/Dockerfile b/comanage-registry-internet2-tier/Dockerfile
index 672145e..cd86a34 100644
--- a/comanage-registry-internet2-tier/Dockerfile
+++ b/comanage-registry-internet2-tier/Dockerfile
@@ -138,7 +138,7 @@ EXPOSE 80 443
 # following line (to prevent other scripts from processing it).
 #####     ENV TIER_BEACON_OPT_OUT True
 
-ENV TIER_RELEASE=210213
+ENV TIER_RELEASE=210910
 ENV TIER_MAINTAINER=tier
 
 ENTRYPOINT ["docker-supervisord-entrypoint"]
diff --git a/comanage-registry-mod-auth-openidc/Dockerfile b/comanage-registry-mod-auth-openidc/Dockerfile
index 39f9774..e615615 100644
--- a/comanage-registry-mod-auth-openidc/Dockerfile
+++ b/comanage-registry-mod-auth-openidc/Dockerfile
@@ -22,7 +22,7 @@ ARG MOD_AUTH_OPENIDC_SRC_URL=https://github.com/zmartzone/mod_auth_openidc/relea
 
 FROM comanage-registry-base:${COMANAGE_REGISTRY_VERSION}-${COMANAGE_REGISTRY_BASE_IMAGE_VERSION} AS comanage
 
-FROM debian:buster AS building
+FROM debian:bullseye AS building
 
 ARG MOD_AUTH_OPENIDC_SRC_URL
 ENV MOD_AUTH_OPENIDC_SRC_URL ${MOD_AUTH_OPENIDC_SRC_URL}
diff --git a/comanage-registry-shibboleth-sp-base/Dockerfile b/comanage-registry-shibboleth-sp-base/Dockerfile
index d6ae470..b8e648d 100644
--- a/comanage-registry-shibboleth-sp-base/Dockerfile
+++ b/comanage-registry-shibboleth-sp-base/Dockerfile
@@ -16,7 +16,7 @@
 # WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
 # See the License for the specific language governing permissions and
 # limitations under the License.
-FROM debian:buster
+FROM debian:bullseye
 
 RUN apt-get update \
       && apt-get install -y --no-install-recommends \
diff --git a/common.bash b/common.bash
index ea4a1a3..4edcf8c 100644
--- a/common.bash
+++ b/common.bash
@@ -1,3 +1,3 @@
 maintainer="i2incommon"
 imagename="comanage-registry"
-COMANAGE_REGISTRY_VERSION="3.3.4"
+COMANAGE_REGISTRY_VERSION="4.0.0-rc1"