diff --git a/.github/workflows/integration_test.yaml b/.github/workflows/integration_test.yaml
index 67f554f3..84d2206e 100644
--- a/.github/workflows/integration_test.yaml
+++ b/.github/workflows/integration_test.yaml
@@ -42,7 +42,9 @@ jobs:
               _, runner, task, variant = job.split(":")
               # Example: "test_charm.py"
               task = task.removeprefix("tests/spread/")
-              if runner.endswith("-arm"):
+              if "s390x" in runner:
+                  architecture = "s390x"
+              elif runner.endswith("-arm"):
                   architecture = "arm64"
               else:
                   architecture = "amd64"
@@ -86,8 +88,9 @@ jobs:
     runs-on: ${{ matrix.job.runner }}
     timeout-minutes: 217  # Sum of steps `timeout-minutes` + 5
     steps:
-      - name: Free up disk space
+      - name: (GitHub hosted) Free up disk space
         timeout-minutes: 1
+        if: ${{ !contains(matrix.job.runner, 'self-hosted') }}
         run: |
           printf '\nDisk usage before cleanup\n'
           df --human-readable
@@ -95,6 +98,10 @@ jobs:
           rm -r /opt/hostedtoolcache/
           printf '\nDisk usage after cleanup\n'
           df --human-readable
+      - name: (IS hosted) Disk usage
+        timeout-minutes: 1
+        if: ${{ contains(matrix.job.runner, 'self-hosted') }}
+        run: df --human-readable
       - name: Checkout
         timeout-minutes: 3
         uses: actions/checkout@v4
diff --git a/spread.yaml b/spread.yaml
index 81fe5689..23e89701 100644
--- a/spread.yaml
+++ b/spread.yaml
@@ -97,6 +97,16 @@ backends:
           username: runner
           variants:
             - -juju29_ubuntu22
+      - self-hosted-linux-s390x-noble-edge:
+          username: ubuntu
+          environment:
+            # Several python packages (e.g. cryptography, bcrypt) do not have s390x builds on PyPI,
+            # so they must be built from source. pkg-config & rust toolchain needed
+            # (These packages are being built when installing poetry or integration test Python
+            # dependencies)
+            CONCIERGE_EXTRA_DEBS: pipx,pkg-config,rustup
+          variants:
+            - -juju29_ubuntu22
 
 suites:
   tests/spread/:
@@ -114,10 +124,18 @@ prepare: |
   snap refresh --hold
   chown -R root:root "$SPREAD_PATH"
   cd "$SPREAD_PATH"
-  snap install --classic concierge
+  # Install via snap after https://github.com/canonical/concierge/pull/81 released
+  go install github.com/canonical/concierge@latest
+
+  # Install charmcraft & pipx on lxd-vm backend and install pipx on IS-hosted runners
+  ~/go/bin/concierge prepare --trace
 
-  # Install charmcraft & pipx (on lxd-vm backend)
-  concierge prepare --trace
+  if [[ $SPREAD_SYSTEM == *"s390x"* ]]
+  then
+    rustup set profile minimal
+    # TODO add renovate comment for rust version
+    rustup default 1.88.0
+  fi
 
   pipx install tox poetry
 prepare-each: |
@@ -129,7 +147,7 @@ prepare-each: |
     poetry add --lock --group integration juju@^2
   fi
   # `concierge prepare` needs to be run for each spread job in case Juju version changed
-  concierge prepare --trace
+  ~/go/bin/concierge prepare --trace
 
   # Unable to set constraint on all models because of Juju bug:
   # https://bugs.launchpad.net/juju/+bug/2065050
diff --git a/tests/integration/markers.py b/tests/integration/markers.py
index 2b73cb73..de8b361f 100644
--- a/tests/integration/markers.py
+++ b/tests/integration/markers.py
@@ -11,3 +11,6 @@
 arm64_only = pytest.mark.skipif(
     architecture.architecture != "arm64", reason="Requires arm64 architecture"
 )
+s390x_only = pytest.mark.skipif(
+    architecture.architecture != "s390x", reason="Requires s390x architecture"
+)
diff --git a/tests/integration/test_architecture.py b/tests/integration/test_architecture.py
index 9440c7af..d9a2944e 100644
--- a/tests/integration/test_architecture.py
+++ b/tests/integration/test_architecture.py
@@ -81,4 +81,34 @@ async def test_amd_charm_on_arm_host(ops_test: OpsTest, charm, series) -> None:
     )
 
 
-# TODO: add s390x test
+@markers.s390x_only
+async def test_amd_charm_on_s390x_host(ops_test: OpsTest, charm, series) -> None:
+    """Tries deploying an amd64 charm on s390x host."""
+    charm = charm.replace("s390x", "amd64")
+
+    await asyncio.gather(
+        ops_test.model.deploy(
+            charm,
+            application_name=MYSQL_ROUTER_APP_NAME,
+            num_units=0,
+            series=series,
+        ),
+        ops_test.model.deploy(
+            MYSQL_TEST_APP_NAME,
+            application_name=MYSQL_TEST_APP_NAME,
+            num_units=1,
+            channel="latest/edge",
+            series=series,
+        ),
+    )
+
+    await ops_test.model.relate(
+        f"{MYSQL_ROUTER_APP_NAME}:database",
+        f"{MYSQL_TEST_APP_NAME}:database",
+    )
+
+    await ops_test.model.wait_for_idle(
+        apps=[MYSQL_ROUTER_APP_NAME],
+        status="error",
+        raise_on_error=False,
+    )
diff --git a/tests/integration/test_data_integrator.py b/tests/integration/test_data_integrator.py
index 96ed3023..bd92beb7 100644
--- a/tests/integration/test_data_integrator.py
+++ b/tests/integration/test_data_integrator.py
@@ -29,7 +29,7 @@
 
 if juju_.is_3_or_higher:
     tls_app_name = "self-signed-certificates"
-    tls_channel = "latest/edge" if architecture.architecture == "arm64" else "latest/stable"
+    tls_channel = "1/edge" if architecture.architecture == "s390x" else "latest/stable"
     tls_config = {"ca-common-name": "Test CA"}
 else:
     tls_app_name = "tls-certificates-operator"
@@ -64,7 +64,7 @@ async def test_external_connectivity_with_data_integrator(
             ops_test.model.deploy(
                 DATA_INTEGRATOR_APP_NAME,
                 application_name=DATA_INTEGRATOR_APP_NAME,
-                channel="latest/stable",
+                channel="latest/edge",  # Use edge for s390x
                 series=series,
                 config=data_integrator_config,
             ),
diff --git a/tests/integration/test_exporter_with_tls.py b/tests/integration/test_exporter_with_tls.py
index 69dbf94e..fd27d4f2 100644
--- a/tests/integration/test_exporter_with_tls.py
+++ b/tests/integration/test_exporter_with_tls.py
@@ -29,7 +29,7 @@
 
 if juju_.is_3_or_higher:
     tls_app_name = "self-signed-certificates"
-    tls_channel = "latest/edge" if architecture.architecture == "arm64" else "latest/stable"
+    tls_channel = "1/edge" if architecture.architecture == "s390x" else "latest/stable"
     tls_config = {"ca-common-name": "Test CA"}
 else:
     tls_app_name = "tls-certificates-operator"
@@ -138,7 +138,6 @@ async def test_exporter_endpoint(ops_test: OpsTest, charm, series) -> None:
         application_name=tls_app_name,
         channel=tls_channel,
         config=tls_config,
-        series="jammy",
     )
     await ops_test.model.wait_for_idle([tls_app_name], status="active", timeout=SLOW_TIMEOUT)
 
diff --git a/tests/integration/test_hacluster.py b/tests/integration/test_hacluster.py
index 04f82872..dc3e6ecc 100644
--- a/tests/integration/test_hacluster.py
+++ b/tests/integration/test_hacluster.py
@@ -35,7 +35,7 @@
 
 if juju_.is_3_or_higher:
     tls_app_name = "self-signed-certificates"
-    tls_channel = "latest/edge" if architecture.architecture == "arm64" else "latest/stable"
+    tls_channel = "1/edge" if architecture.architecture == "s390x" else "latest/stable"
     tls_config = {"ca-common-name": "Test CA"}
 else:
     tls_app_name = "tls-certificates-operator"
@@ -111,7 +111,7 @@ async def test_external_connectivity_vip_with_hacluster(ops_test: OpsTest, charm
             ops_test.model.deploy(
                 DATA_INTEGRATOR_APP_NAME,
                 application_name=DATA_INTEGRATOR_APP_NAME,
-                channel="latest/stable",
+                channel="latest/edge",  # Use edge for s390x
                 series=series,
                 config={"database-name": TEST_DATABASE},
                 num_units=4,
diff --git a/tests/integration/test_tls.py b/tests/integration/test_tls.py
index ea7cdd51..1ec8510b 100644
--- a/tests/integration/test_tls.py
+++ b/tests/integration/test_tls.py
@@ -26,7 +26,7 @@
 
 if juju_.is_3_or_higher:
     tls_app_name = "self-signed-certificates"
-    tls_channel = "latest/edge" if architecture.architecture == "arm64" else "latest/stable"
+    tls_channel = "1/edge" if architecture.architecture == "s390x" else "latest/stable"
     tls_config = {"ca-common-name": "Test CA"}
 else:
     tls_app_name = "tls-certificates-operator"
@@ -61,7 +61,6 @@ async def test_build_deploy_and_relate(ops_test: OpsTest, charm, series) -> None
                 application_name=tls_app_name,
                 channel=tls_channel,
                 config=tls_config,
-                series="jammy",
             ),
             ops_test.model.deploy(
                 TEST_APP_NAME,
diff --git a/tests/integration/test_upgrade.py b/tests/integration/test_upgrade.py
index 53a57ec0..c54db9d3 100644
--- a/tests/integration/test_upgrade.py
+++ b/tests/integration/test_upgrade.py
@@ -214,9 +214,10 @@ def create_valid_upgrade_charm(charm_file: typing.Union[str, pathlib.Path]) -> N
 
     # charm needs to refresh snap to be able to avoid no-op when upgrading.
     # set an old revision of the snap
-    versions["snap"]["revisions"]["x86_64"] = "121"
-    versions["snap"]["revisions"]["aarch64"] = "122"
-    versions["workload"] = "8.0.39"
+    versions["snap"]["revisions"]["x86_64"] = "148"
+    versions["snap"]["revisions"]["aarch64"] = "150"
+    versions["snap"]["revisions"]["s390x"] = "149"
+    versions["workload"] = "8.0.42"
 
     with zipfile.ZipFile(charm_file, mode="a") as charm_zip:
         charm_zip.writestr("refresh_versions.toml", tomli_w.dumps(versions))
diff --git a/tests/spread/test_architecture.py/task.yaml b/tests/spread/test_architecture.py/task.yaml
deleted file mode 100644
index cad86336..00000000
--- a/tests/spread/test_architecture.py/task.yaml
+++ /dev/null
@@ -1,9 +0,0 @@
-summary: test_architecture.py
-environment:
-  TEST_MODULE: test_architecture.py
-execute: |
-  tox run -e integration -- "tests/integration/$TEST_MODULE" --model testing --alluredir="$SPREAD_TASK/allure-results"
-artifacts:
-  - allure-results
-backends:
-  - -lxd-vm  # This task requires charm built on different architecture from host
diff --git a/tests/spread/test_data_integrator.py/task.yaml b/tests/spread/test_data_integrator.py/task.yaml
deleted file mode 100644
index 9d5bc3a5..00000000
--- a/tests/spread/test_data_integrator.py/task.yaml
+++ /dev/null
@@ -1,7 +0,0 @@
-summary: test_data_integrator.py
-environment:
-  TEST_MODULE: test_data_integrator.py
-execute: |
-  tox run -e integration -- "tests/integration/$TEST_MODULE" --model testing --alluredir="$SPREAD_TASK/allure-results"
-artifacts:
-  - allure-results
diff --git a/tests/spread/test_database.py/task.yaml b/tests/spread/test_database.py/task.yaml
deleted file mode 100644
index ab87406f..00000000
--- a/tests/spread/test_database.py/task.yaml
+++ /dev/null
@@ -1,7 +0,0 @@
-summary: test_database.py
-environment:
-  TEST_MODULE: test_database.py
-execute: |
-  tox run -e integration -- "tests/integration/$TEST_MODULE" --model testing --alluredir="$SPREAD_TASK/allure-results"
-artifacts:
-  - allure-results
diff --git a/tests/spread/test_exporter.py/task.yaml b/tests/spread/test_exporter.py/task.yaml
deleted file mode 100644
index 647ca870..00000000
--- a/tests/spread/test_exporter.py/task.yaml
+++ /dev/null
@@ -1,7 +0,0 @@
-summary: test_exporter.py
-environment:
-  TEST_MODULE: test_exporter.py
-execute: |
-  tox run -e integration -- "tests/integration/$TEST_MODULE" --model testing --alluredir="$SPREAD_TASK/allure-results"
-artifacts:
-  - allure-results
diff --git a/tests/spread/test_exporter_with_tls.py/task.yaml b/tests/spread/test_exporter_with_tls.py/task.yaml
deleted file mode 100644
index 5974f89f..00000000
--- a/tests/spread/test_exporter_with_tls.py/task.yaml
+++ /dev/null
@@ -1,7 +0,0 @@
-summary: test_exporter_with_tls.py
-environment:
-  TEST_MODULE: test_exporter_with_tls.py
-execute: |
-  tox run -e integration -- "tests/integration/$TEST_MODULE" --model testing --alluredir="$SPREAD_TASK/allure-results"
-artifacts:
-  - allure-results
diff --git a/tests/spread/test_log_rotation.py/task.yaml b/tests/spread/test_log_rotation.py/task.yaml
deleted file mode 100644
index 8e890011..00000000
--- a/tests/spread/test_log_rotation.py/task.yaml
+++ /dev/null
@@ -1,7 +0,0 @@
-summary: test_log_rotation.py
-environment:
-  TEST_MODULE: test_log_rotation.py
-execute: |
-  tox run -e integration -- "tests/integration/$TEST_MODULE" --model testing --alluredir="$SPREAD_TASK/allure-results"
-artifacts:
-  - allure-results
diff --git a/tests/spread/test_subordinate_charms.py/task.yaml b/tests/spread/test_subordinate_charms.py/task.yaml
deleted file mode 100644
index 3b281deb..00000000
--- a/tests/spread/test_subordinate_charms.py/task.yaml
+++ /dev/null
@@ -1,9 +0,0 @@
-summary: test_subordinate_charms.py
-environment:
-  TEST_MODULE: test_subordinate_charms.py
-execute: |
-  tox run -e integration -- "tests/integration/$TEST_MODULE" --model testing --alluredir="$SPREAD_TASK/allure-results"
-artifacts:
-  - allure-results
-backends:
-  - -lxd-vm  # Requires CI secrets
diff --git a/tests/spread/test_upgrade.py/task.yaml b/tests/spread/test_upgrade.py/task.yaml
deleted file mode 100644
index a53e8a4e..00000000
--- a/tests/spread/test_upgrade.py/task.yaml
+++ /dev/null
@@ -1,7 +0,0 @@
-summary: test_upgrade.py
-environment:
-  TEST_MODULE: test_upgrade.py
-execute: |
-  tox run -e integration -- "tests/integration/$TEST_MODULE" --model testing --alluredir="$SPREAD_TASK/allure-results"
-artifacts:
-  - allure-results