diff --git a/opensciencegrid/gracc-apel/Dockerfile b/opensciencegrid/gracc-apel/Dockerfile
index a7d40fc9..bf5789cc 100644
--- a/opensciencegrid/gracc-apel/Dockerfile
+++ b/opensciencegrid/gracc-apel/Dockerfile
@@ -1,5 +1,5 @@
 ARG BASE_OS=el9
-ARG BASE_OSG_SERIES=3.6
+ARG BASE_OSG_SERIES=23
 ARG BASE_YUM_REPO=release
 
 FROM hub.opensciencegrid.org/opensciencegrid/software-base:$BASE_OSG_SERIES-$BASE_OS-$BASE_YUM_REPO
@@ -8,23 +8,28 @@ FROM hub.opensciencegrid.org/opensciencegrid/software-base:$BASE_OSG_SERIES-$BAS
 ARG BASE_OS
 
 # install dependencies
-RUN yum -y install python3 python3-pip && \
-  pip3 install opensearch-py requests && \
-  pip3 install argo-ams-library
-RUN yum -y install http://rpm-repo.argo.grnet.gr/ARGO/devel/centos7/python-argo-ams-library-0.5.5-20210415071520.ff0c536.$BASE_OS.noarch.rpm
-
-RUN yum -y install python-dirq
-
-# install ca-policy-egi-core
-RUN yum -y remove osg-ca-certs
-RUN curl -so /etc/yum.repos.d/EGI-trustanchors.repo https://repository.egi.eu/sw/production/cas/1/current/repo-files/egi-trustanchors.repo && \
-  yum -y install ca-policy-egi-core
-
-
-RUN yum -y install https://github.com/apel/ssm/releases/download/3.2.1-1/apel-ssm-3.2.1-1.$BASE_OS.noarch.rpm  && \
-  mkdir /etc/grid-security/apel && \
-  mkdir -p /var/spool/apel/outgoing/12345678 && \
-  { fetch-crl -p10 -T10 || :; }
+RUN    dnf install -y \
+         python3 \
+         python3-dirq \
+         python3-pip \
+         https://github.com/apel/ssm/releases/download/3.4.0-1/apel-ssm-3.4.0-1.$BASE_OS.noarch.rpm \
+# ARGO AMS
+    && dnf install -y \
+         --repofrompath argo,http://rpm-repo.argo.grnet.gr/ARGO/prod/rocky9/ \
+         --nogpgcheck \
+         python3-argo-ams-library \
+# EGI CA certificates
+    && dnf config-manager --add-repo \
+         https://repository.egi.eu/sw/production/cas/1/current/repo-files/egi-trustanchors.repo \
+    && dnf swap -y osg-ca-certs ca-policy-egi-core \
+    && dnf clean all
+
+RUN    pip3 install --no-cache-dir \
+         opensearch-py \
+         requests
+
+RUN    mkdir /etc/grid-security/apel \
+    && mkdir -p /var/spool/apel/outgoing/12345678
 
 COPY apel_report.py normal_hepspec docker-run.sh /usr/libexec/apel/
 COPY sender.cfg /etc/apel/