diff --git a/.pre-commit-config.yaml b/.pre-commit-config.yaml
index a3ade226..37fc3bc2 100644
--- a/.pre-commit-config.yaml
+++ b/.pre-commit-config.yaml
@@ -9,7 +9,7 @@ repos:
       - id: trailing-whitespace
       - id: end-of-file-fixer
   - repo: https://github.com/astral-sh/ruff-pre-commit
-    rev: v0.14.11
+    rev: v0.15.0
     hooks:
       - id: ruff-format
         types_or: [python, pyi, jupyter]
@@ -21,7 +21,7 @@ repos:
     hooks:
       - id: markdownlint-fix
   - repo: https://github.com/kynan/nbstripout
-    rev: 0.8.2
+    rev: 0.9.0
     hooks:
       - id: nbstripout
         files: ".ipynb"
diff --git a/docs/user-guide/add-region.ipynb b/docs/user-guide/add-region.ipynb
index 8ab1a791..fcc9c22b 100644
--- a/docs/user-guide/add-region.ipynb
+++ b/docs/user-guide/add-region.ipynb
@@ -112,11 +112,11 @@
     "    )\n",
     "    g = sns.FacetGrid(data=sector_capacity, col=\"region\")\n",
     "    g.map_dataframe(\n",
-    "        lambda data, **kwargs: data.pivot(\n",
-    "            index=\"year\", columns=\"technology\", values=\"capacity\"\n",
+    "        lambda data, **kwargs: (\n",
+    "            data.pivot(index=\"year\", columns=\"technology\", values=\"capacity\")\n",
+    "            .reindex(all_years)\n",
+    "            .plot(kind=\"bar\", stacked=True, ax=plt.gca())\n",
     "        )\n",
-    "        .reindex(all_years)\n",
-    "        .plot(kind=\"bar\", stacked=True, ax=plt.gca())\n",
     "    )\n",
     "    g.add_legend()\n",
     "    g.set_ylabels(\"Capacity (PJ)\")\n",
diff --git a/src/muse/outputs/cache.py b/src/muse/outputs/cache.py
index 0c00eb09..eb0b8efe 100644
--- a/src/muse/outputs/cache.py
+++ b/src/muse/outputs/cache.py
@@ -384,10 +384,12 @@ def check_col(colname: str) -> str:
         return colname
 
     return reduce(
-        lambda left, right: pd.DataFrame.merge(left, right, how="outer", on=cols)
-        .T.groupby(check_col)
-        .last()
-        .T,
+        lambda left, right: (
+            pd.DataFrame.merge(left, right, how="outer", on=cols)
+            .T.groupby(check_col)
+            .last()
+            .T
+        ),
         data,
     )
 
diff --git a/tests/test_minimum_service.py b/tests/test_minimum_service.py
index c75d7479..50545ff1 100644
--- a/tests/test_minimum_service.py
+++ b/tests/test_minimum_service.py
@@ -71,10 +71,14 @@ def test_minimum_service_factor(check_mock, tmp_path, minimum_service_factors):
     for process, service_factor in zip(processes, minimum_service_factors):
         supply_process = supply[supply.technology == process]
         supply_process.loc[:, "min_supply"] = supply_process.apply(
-            lambda x: x.capacity
-            * service_factor[x.timeslice]
-            * float(
-                techno_out[techno_out.ProcessName == process]["electricity"].values[0]
+            lambda x: (
+                x.capacity
+                * service_factor[x.timeslice]
+                * float(
+                    techno_out[techno_out.ProcessName == process]["electricity"].values[
+                        0
+                    ]
+                )
             ),
             axis=1,
         )