diff --git a/.gitea/workflows/build.yml b/.gitea/workflows/build.yml
index 592f612..94811be 100644
--- a/.gitea/workflows/build.yml
+++ b/.gitea/workflows/build.yml
@@ -66,7 +66,11 @@ jobs:
 
       - name: Install backend + test deps
         run: |
-          /tmp/venv/bin/pip install /tmp/wheels/*.whl pytest pytest-asyncio httpx aioresponses prometheus_client
+          # Pin aiohttp <3.14: aioresponses 0.7.8 (latest) doesn't pass the
+          # stream_writer kwarg that aiohttp 3.14 made required on ClientResponse,
+          # breaking every aioresponses-mocked test. Drop once aioresponses ships
+          # an aiohttp-3.14-compatible release.
+          /tmp/venv/bin/pip install /tmp/wheels/*.whl pytest pytest-asyncio httpx aioresponses 'aiohttp<3.14' prometheus_client
 
       - name: Run pytest
         env:
diff --git a/.gitea/workflows/release.yml b/.gitea/workflows/release.yml
index 008c2cd..01fcd7b 100644
--- a/.gitea/workflows/release.yml
+++ b/.gitea/workflows/release.yml
@@ -33,7 +33,11 @@ jobs:
 
       - name: Install backend + test deps
         run: |
-          /tmp/venv/bin/pip install /tmp/wheels/*.whl pytest pytest-asyncio httpx aioresponses prometheus_client
+          # Pin aiohttp <3.14: aioresponses 0.7.8 (latest) doesn't pass the
+          # stream_writer kwarg that aiohttp 3.14 made required on ClientResponse,
+          # breaking every aioresponses-mocked test. Drop once aioresponses ships
+          # an aiohttp-3.14-compatible release.
+          /tmp/venv/bin/pip install /tmp/wheels/*.whl pytest pytest-asyncio httpx aioresponses 'aiohttp<3.14' prometheus_client
 
       - name: Run pytest
         env: