diff --git a/.github/workflows/ci.yml b/.github/workflows/ci.yml
index bcc32fb..5337b23 100644
--- a/.github/workflows/ci.yml
+++ b/.github/workflows/ci.yml
@@ -34,9 +34,9 @@ jobs:
   build:
     name: Build charms
     needs: unit-tests
-    uses: canonical/data-platform-workflows/.github/workflows/build_charms_with_cache.yaml@v4
+    uses: canonical/data-platform-workflows/.github/workflows/build_charm.yaml@v23
     with:
-      artifact-name: charm-packed
+      charmcraft-snap-channel: 3.x/stable
 
 
   channel:
@@ -93,7 +93,7 @@ jobs:
         env:
           CHARMCRAFT_AUTH: ${{ secrets.CHARMCRAFT_AUTH }}
         run: |
-          sudo snap install charmcraft --classic
+          sudo snap install charmcraft --channel 3.x/stable --classic
           charmcraft upload ${{ steps.download.outputs.download-path }}/*.charm \
             --name $CHARM_NAME \
             --release ${{ needs.channel.outputs.test }}
@@ -188,7 +188,7 @@ jobs:
     steps:
     - name: Install Charmcraft
       run: |
-        sudo snap install charmcraft --classic
+        sudo snap install charmcraft --channel 3.x/stable --classic
 
     - name: Get uploaded revision
       id: revision
diff --git a/charmcraft.yaml b/charmcraft.yaml
index a1b57db..8f15b7a 100644
--- a/charmcraft.yaml
+++ b/charmcraft.yaml
@@ -2,33 +2,11 @@ type: charm
 parts:
   charm:
     charm-python-packages: [setuptools,markdown]
-bases:
-    - build-on:
-        - name: ubuntu
-          channel: "24.04"
-          architectures: ["amd64"]
-      run-on:
-        - name: ubuntu
-          channel: "24.04"
-          architectures:
-              - amd64
-              - arm64
-              - s390x
-              - ppc64el
-              - riscv64
-        - name: ubuntu
-          channel: "22.04"
-          architectures:
-              - amd64
-              - arm64
-              - s390x
-              - ppc64el
-              - riscv64
-        - name: ubuntu
-          channel: "20.04"
-          architectures:
-              - amd64
-              - arm64
-              - s390x
-              - ppc64el
-              - riscv64
+    build-packages:
+      - cargo
+base: ubuntu@24.04
+platforms:
+  amd64:
+  arm64:
+  s390x:
+  ppc64el:
diff --git a/flake.lock b/flake.lock
new file mode 100644
index 0000000..4583957
--- /dev/null
+++ b/flake.lock
@@ -0,0 +1,27 @@
+{
+  "nodes": {
+    "nixpkgs": {
+      "locked": {
+        "lastModified": 1731797254,
+        "narHash": "sha256-df3dJApLPhd11AlueuoN0Q4fHo/hagP75LlM5K1sz9g=",
+        "owner": "nixos",
+        "repo": "nixpkgs",
+        "rev": "e8c38b73aeb218e27163376a2d617e61a2ad9b59",
+        "type": "github"
+      },
+      "original": {
+        "owner": "nixos",
+        "ref": "nixos-24.05",
+        "repo": "nixpkgs",
+        "type": "github"
+      }
+    },
+    "root": {
+      "inputs": {
+        "nixpkgs": "nixpkgs"
+      }
+    }
+  },
+  "root": "root",
+  "version": 7
+}
diff --git a/flake.nix b/flake.nix
new file mode 100644
index 0000000..7d72a07
--- /dev/null
+++ b/flake.nix
@@ -0,0 +1,37 @@
+{
+  description = "juju controller charm shell";
+  inputs = {
+    nixpkgs.url = "github:nixos/nixpkgs/nixos-24.05";
+  };
+
+  outputs = { self, nixpkgs, ... } @ inputs:
+    let
+      forAllSystems = inputs.nixpkgs.lib.genAttrs [
+        "aarch64-linux"
+        "x86_64-linux"
+        "aarch64-darwin"
+      ];
+    in
+    {
+      devShells = forAllSystems (system: {
+        default =
+          let
+            pkgs = nixpkgs.legacyPackages.${system};
+          in
+          pkgs.mkShell {
+            name = "juju-controller-charm";
+            # Enable experimental features without having to specify the argument
+            NIX_CONFIG = "experimental-features = nix-command flakes";
+            nativeBuildInputs = with pkgs; [
+              coreutils
+              findutils
+              zsh
+              python312
+            ];
+            shellHook = ''
+              exec zsh
+            '';
+          };
+      });
+    };
+}
\ No newline at end of file
diff --git a/src/charm.py b/src/charm.py
index 5ad3923..d0ccffb 100755
--- a/src/charm.py
+++ b/src/charm.py
@@ -130,6 +130,8 @@ def _on_metrics_endpoint_relation_created(self, event: RelationJoinedEvent):
             api_port = self.api_port()
         except AgentConfException as e:
             logger.error('cannot read controller API port from agent configuration: %s', e)
+            self.unit.status = BlockedStatus(
+                f"cannot read controller API port from agent configuration: {e}")
             return
 
         metrics_endpoint = MetricsEndpointProvider(
diff --git a/tests/test_charm.py b/tests/test_charm.py
index d39f263..d61566f 100644
--- a/tests/test_charm.py
+++ b/tests/test_charm.py
@@ -9,7 +9,7 @@
 import yaml
 
 from charm import JujuControllerCharm, AgentConfException
-from ops.model import BlockedStatus, ActiveStatus
+from ops import BlockedStatus, ActiveStatus
 from ops.testing import Harness
 from unittest.mock import mock_open, patch
 
@@ -139,7 +139,10 @@ def test_apiaddresses_missing_status(self, *_):
 
         harness.add_relation('metrics-endpoint', 'prometheus-k8s')
         harness.evaluate_status()
-        self.assertIsInstance(harness.charm.unit.status, BlockedStatus)
+        self.assertEqual(harness.charm.unit.status, BlockedStatus(
+            "cannot read controller API port from agent configuration: "
+            "agent.conf key 'apiaddresses' missing"
+        ))
 
     @patch("builtins.open", new_callable=mock_open, read_data=agent_conf_ipv4)
     def test_apiaddresses_ipv4(self, _):