diff --git a/.github/workflows/test.yml b/.github/workflows/test.yml
index 99499246..008702b9 100644
--- a/.github/workflows/test.yml
+++ b/.github/workflows/test.yml
@@ -86,7 +86,7 @@ jobs:
           cache: 'yarn'
       -
         name: Install
-        run: yarn install
+        run: yarn install --immutable
       -
         name: Create includes
         id: set
@@ -197,7 +197,7 @@ jobs:
           use: false
       -
         name: Install
-        run: yarn install
+        run: yarn install --immutable
       -
         name: Test
         uses: actions/github-script@3a2844b7e9c422d3c10d287c895573f7108da1b3 # v9.0.0
diff --git a/dev.Dockerfile b/dev.Dockerfile
index cc583456..0f729fec 100644
--- a/dev.Dockerfile
+++ b/dev.Dockerfile
@@ -36,7 +36,7 @@ FROM base AS deps
 RUN --mount=type=bind,target=.,rw \
   --mount=type=cache,target=/src/.yarn/cache \
   --mount=type=cache,target=/src/node_modules \
-  yarn install && mkdir /vendor && cp yarn.lock /vendor
+  yarn install --immutable && mkdir /vendor && cp yarn.lock /vendor
 
 FROM scratch AS vendor-update
 COPY --from=deps /vendor /