diff --git a/.github/actions/install_compatibility_layer/entrypoint.sh b/.github/actions/install_compatibility_layer/entrypoint.sh
index aca33c96..b4904ddd 100755
--- a/.github/actions/install_compatibility_layer/entrypoint.sh
+++ b/.github/actions/install_compatibility_layer/entrypoint.sh
@@ -5,7 +5,7 @@ cat << EOF > hosts
 127.0.0.1 eessi_host_arch=$(uname -m) eessi_host_os=linux
 EOF
 
-ansible-playbook --connection=local --inventory=hosts -e ansible_python_interpreter=python3 -e gentoo_prefix_path=$1 ${GITHUB_WORKSPACE}/ansible/playbooks/install.yml
+ansible-playbook -v --connection=local --inventory=hosts -e ansible_python_interpreter=python3 -e gentoo_prefix_path=$1 ${GITHUB_WORKSPACE}/ansible/playbooks/install.yml
 
 # A successful installation should at least have Lmod and archspec,
 # so let's  check if we can use them.
diff --git a/ansible/playbooks/roles/compatibility_layer/files/sync_gentoo_cache b/ansible/playbooks/roles/compatibility_layer/files/sync_gentoo_cache
new file mode 100755
index 00000000..65b4f709
--- /dev/null
+++ b/ansible/playbooks/roles/compatibility_layer/files/sync_gentoo_cache
@@ -0,0 +1,34 @@
+#!/bin/bash
+
+repository_name="${1}"
+repository_path="${3}"
+
+[[ ${repository_name} == "gentoo" ]] || exit 0
+
+source $(portageq envvar EPREFIX)/lib/gentoo/functions.sh
+
+# Number of jobs for egencache, default is number or processors.
+parallel_jobs="$(nproc)"
+
+if [[ -f ${repository_path}/metadata/timestamp.x ]]; then
+	portage_current_timestamp=$(cut -f 1 -d " " "${repository_path}/metadata/timestamp.x" )
+else
+	portage_current_timestamp=0
+fi
+
+ebegin "Fetching metadata timestamp for ${repository_name}"
+rsync -aq rsync://rsync.gentoo.org/gentoo-portage/metadata/timestamp.x "${repository_path}"/metadata/timestamp.x
+eend $?
+portage_new_timestamp=$(cut -f 1 -d " " "${repository_path}/metadata/timestamp.x" )
+
+if [[ ${portage_current_timestamp} -lt ${portage_new_timestamp} ]]; then
+	ebegin "Fetching pre-generated metadata cache for ${repository_name}"
+	rsync -aq rsync://rsync.gentoo.org/gentoo-portage/metadata/md5-cache/ "${repository_path}"/metadata/md5-cache/
+	eend $?
+else
+	einfo "Metadata cache for ${repository_name} already recent, no need to fetch it :-)"
+fi
+
+ebegin "Updating metadata cache for ${repository_name}"
+egencache --jobs="${parallel_jobs}" --repo="${repository_name}" --update --update-use-local-desc
+eend $?
diff --git a/ansible/playbooks/roles/compatibility_layer/files/sync_gentoo_dtd b/ansible/playbooks/roles/compatibility_layer/files/sync_gentoo_dtd
new file mode 100755
index 00000000..c12f6c3b
--- /dev/null
+++ b/ansible/playbooks/roles/compatibility_layer/files/sync_gentoo_dtd
@@ -0,0 +1,17 @@
+#!/bin/bash
+
+repository_name="${1}"
+repository_path="${3}"
+
+[[ ${repository_name} == "gentoo" ]] || exit 0
+
+source $(portageq envvar EPREFIX)/lib/gentoo/functions.sh
+
+DTDDIR="${repository_path}"/metadata/dtd
+ebegin "Updating DTDs"
+if [[ -e ${DTDDIR} ]]; then
+	git -C "${DTDDIR}" pull -q --ff-only
+else
+	git clone -q https://anongit.gentoo.org/git/data/dtd.git "${DTDDIR}"
+fi
+eend "$?"
diff --git a/ansible/playbooks/roles/compatibility_layer/files/sync_gentoo_glsa b/ansible/playbooks/roles/compatibility_layer/files/sync_gentoo_glsa
new file mode 100755
index 00000000..e2a2face
--- /dev/null
+++ b/ansible/playbooks/roles/compatibility_layer/files/sync_gentoo_glsa
@@ -0,0 +1,17 @@
+#!/bin/bash
+
+repository_name="${1}"
+repository_path="${3}"
+
+[[ ${repository_name} == "gentoo" ]] || exit 0
+
+source $(portageq envvar EPREFIX)/lib/gentoo/functions.sh
+
+GLSADIR="${repository_path}"/metadata/glsa
+ebegin "Updating GLSAs"
+if [[ -e ${GLSADIR} ]]; then
+	git -C "${GLSADIR}" pull -q --ff-only
+else
+	git clone -q https://anongit.gentoo.org/git/data/glsa.git "${GLSADIR}"
+fi
+eend "$?"
diff --git a/ansible/playbooks/roles/compatibility_layer/files/sync_gentoo_news b/ansible/playbooks/roles/compatibility_layer/files/sync_gentoo_news
new file mode 100755
index 00000000..92c69a63
--- /dev/null
+++ b/ansible/playbooks/roles/compatibility_layer/files/sync_gentoo_news
@@ -0,0 +1,17 @@
+#!/bin/bash
+
+repository_name="${1}"
+repository_path="${3}"
+
+[[ ${repository_name} == "gentoo" ]] || exit 0
+
+source $(portageq envvar EPREFIX)/lib/gentoo/functions.sh
+
+NEWSDIR="${repository_path}"/metadata/news
+ebegin "Updating news items"
+if [[ -e ${NEWSDIR} ]]; then
+	git -C "${NEWSDIR}" pull -q --ff-only
+else
+	git clone -q https://anongit.gentoo.org/git/data/gentoo-news.git "${NEWSDIR}"
+fi
+eend $? "Try to remove ${NEWSDIR}"
diff --git a/ansible/playbooks/roles/compatibility_layer/files/sync_gentoo_projects_xml b/ansible/playbooks/roles/compatibility_layer/files/sync_gentoo_projects_xml
new file mode 100644
index 00000000..fe1ac0e9
--- /dev/null
+++ b/ansible/playbooks/roles/compatibility_layer/files/sync_gentoo_projects_xml
@@ -0,0 +1,12 @@
+#!/bin/bash
+
+repository_name="${1}"
+repository_path="${3}"
+
+[[ ${repository_name} == "gentoo" ]] || exit 0
+
+source $(portageq envvar EPREFIX)/lib/gentoo/functions.sh
+
+ebegin "Updating projects.xml"
+wget -q -P "${repository_path}"/metadata/ -N https://api.gentoo.org/metastructure/projects.xml
+eend $?
diff --git a/ansible/playbooks/roles/compatibility_layer/files/sync_overlay_cache b/ansible/playbooks/roles/compatibility_layer/files/sync_overlay_cache
new file mode 100755
index 00000000..e7f5ecf0
--- /dev/null
+++ b/ansible/playbooks/roles/compatibility_layer/files/sync_overlay_cache
@@ -0,0 +1,14 @@
+#!/bin/bash
+
+repository_name="${1}"
+
+[[ ${repository_name} == "gentoo" ]] && exit 0
+
+source $(portageq envvar EPREFIX)/lib/gentoo/functions.sh
+
+# Number of jobs for egencache, default is number or processors.
+parallel_jobs="$(nproc)"
+
+ebegin "Updating metadata cache for ${repository_name}"
+egencache --jobs="${parallel_jobs}" --repo="${repository_name}" --update --update-use-local-desc
+eend $?
diff --git a/ansible/playbooks/roles/compatibility_layer/tasks/add_overlay.yml b/ansible/playbooks/roles/compatibility_layer/tasks/add_overlay.yml
index 28a81364..0454e1aa 100644
--- a/ansible/playbooks/roles/compatibility_layer/tasks/add_overlay.yml
+++ b/ansible/playbooks/roles/compatibility_layer/tasks/add_overlay.yml
@@ -58,6 +58,46 @@
         selectattr('eclass-overrides', 'equalto', True) | map(attribute='name') | join(' ')
       }}
 
+- name: Use git instead of rsync for the Gentoo overlay
+  copy:
+    dest: "{{ gentoo_prefix_path }}/etc/portage/repos.conf/gentoo.conf"
+    mode: "0644"
+    content: |
+      [DEFAULT]
+      main-repo = gentoo
+      sync-git-pull-extra-opts = --quiet
+
+      [gentoo]
+      priority  = 1
+      location  = {{ gentoo_prefix_path }}/var/db/repos/gentoo
+      sync-uri  = https://github.com/gentoo/gentoo.git
+      sync-type = git
+      auto-sync = Yes
+      clone-depth = 1
+
+- name: Create repo.postsync.d directory
+  file:
+    path: "{{ gentoo_prefix_path }}/etc/portage/repo.postsync.d"
+    state: directory
+    mode: '0755'
+
+- name: Add post-sync hooks for Gentoo overlay
+  copy:
+    src: "{{ item }}"
+    dest: "{{ gentoo_prefix_path }}/etc/portage/repo.postsync.d/{{ item }}"
+    mode: 0755
+  with_items:
+    - sync_gentoo_cache
+    - sync_gentoo_dtd
+    - sync_gentoo_glsa
+    - sync_gentoo_news
+    - sync_overlay_cache
+
+- name: Remove the old Gentoo overlay directory
+  file:
+    state: absent
+    path: "{{ gentoo_prefix_path }}/var/db/repos/gentoo"
+
 - name: Sync the repositories
   portage:
     sync: 'yes'
@@ -77,3 +117,11 @@
     force: yes
   with_items:
     "{{ find_configs.results | rejectattr('files', 'equalto', []) | map(attribute='files') | list }}"
+
+- name: Update system set if we are running in an existing Prefix installation
+  portage:
+    changed_use: yes
+    deep: yes
+    package: "@world"
+    update: yes
+  when: startprefix.stat.exists
diff --git a/test/compat_layer.py b/test/compat_layer.py
index 2e2fb745..c45e35c5 100644
--- a/test/compat_layer.py
+++ b/test/compat_layer.py
@@ -183,6 +183,26 @@ def __init__(self):
             sn.assert_found(f'\n/{self.symlink_to_host}\n', self.stdout),
         ])
 
+        
+@rfm.simple_test
+class GentooOverlayGitTest(RunInGentooPrefixTest):
+    def __init__(self):
+        # the switch to git was made in pilot version 2021.06
+        self.skip_if(self.eessi_version == '2021.03')
+
+        super().__init__()
+        self.descr = 'Verify that the Gentoo overlay is synced using git.'
+        self.command = f'emerge --info'
+
+        gentoo_repo_dir = os.path.join(self.compat_dir, 'var', 'db', 'repos', 'gentoo')
+        gentoo_git_repo_info = '''gentoo
+    location: %s
+    sync-type: git
+    sync-uri: https://github.com/gentoo/gentoo.git''' % gentoo_repo_dir
+
+        self.sanity_patterns = sn.assert_found(gentoo_git_repo_info, self.stdout)
+
+        
 @rfm.simple_test
 class GlibcEnvFileTest(RunInGentooPrefixTest):
     def __init__(self):