diff --git a/.circleci/config.yml b/.circleci/config.yml
index 6b2bac12b91..40082e17d2e 100644
--- a/.circleci/config.yml
+++ b/.circleci/config.yml
@@ -431,6 +431,8 @@ jobs:
 
   test_aio_local:
     executor: default-executor
+    environment:
+      RXJS_VERSION_7: '7.1.0'
     steps:
       - custom_attach_workspace
       - init_environment
@@ -446,7 +448,15 @@ jobs:
         # Check the bundle sizes.
       - run: yarn --cwd aio payload-size aio-local
         # Run tests with RxJS v7.
-      - run: yarn --cwd aio add rxjs@7.1.0
+      - run: yarn --cwd aio add rxjs@$RXJS_VERSION_7 && yarn --cwd aio aio-use-local
+      - run:
+          name: Ensure we use RxJS v7
+          command: >-
+            node --eval "
+              const expected = process.env.RXJS_VERSION_7;
+              const actual = require('./aio/node_modules/rxjs/package.json').version;
+              assert(actual === expected, 'Expected RxJS v' + expected + ', but found v' + actual + '.');
+            "
       - run: yarn --cwd aio test --progress=false --watch=false
 
   test_aio_tools:
@@ -466,6 +476,8 @@ jobs:
       name: default-executor
       resource_class: xlarge
     parallelism: 5
+    environment:
+      RXJS_VERSION_7: '7.1.0'
     steps:
       - custom_attach_workspace
       - init_environment
@@ -477,8 +489,16 @@ jobs:
         # with either "0", "1", etc as node index. This can be passed to the "--shard" argument.
       - run: yarn --cwd aio example-e2e --setup --local --cliSpecsConcurrency=5 --shard=${CIRCLE_NODE_INDEX}/${CIRCLE_NODE_TOTAL}
         # Run tests with RxJS v7.
-        # (Exclude some examples that are not yet compatible with v7.)
-      - run: yarn --cwd aio/tools/examples/shared add rxjs@7.1.0 && yarn --cwd aio boilerplate:add
+      - run: yarn --cwd aio/tools/examples/shared add rxjs@$RXJS_VERSION_7 && yarn --cwd aio example-use-local && yarn --cwd aio boilerplate:add
+      - run:
+          name: Ensure we use RxJS v7
+          command: >-
+            node --eval "
+              const expected = process.env.RXJS_VERSION_7;
+              const actual = require('./aio/tools/examples/shared/node_modules/rxjs/package.json').version;
+              assert(actual === expected, 'Expected RxJS v' + expected + ', but found v' + actual + '.');
+            "
+        # Exclude some examples that are not yet compatible with v7.
       - run: yarn --cwd aio example-e2e --cliSpecsConcurrency=5 --shard=${CIRCLE_NODE_INDEX}/${CIRCLE_NODE_TOTAL} --exclude=practical-observable-usage --exclude=upgrade-module --exclude=upgrade-phonecat
 
   # This job should only be run on PR builds, where `CI_PULL_REQUEST` is not `false`.
@@ -492,7 +512,7 @@ jobs:
       - run: ./aio/scripts/build-artifacts.sh $AIO_SNAPSHOT_ARTIFACT_PATH $CI_PULL_REQUEST $CI_COMMIT
       - store_artifacts:
           path: *aio_preview_artifact_path
-          # The `destination` needs to be kept in synch with the value of
+          # The `destination` needs to be kept in sync with the value of
           # `AIO_ARTIFACT_PATH` in `aio/aio-builds-setup/Dockerfile`
           destination: aio/dist/aio-snapshot.tgz
       - run: node ./aio/scripts/create-preview $CIRCLE_BUILD_NUM