diff --git a/.circleci/config.yml b/.circleci/config.yml
index 2902bcd..f1140aa 100644
--- a/.circleci/config.yml
+++ b/.circleci/config.yml
@@ -28,7 +28,7 @@ jobs:
     steps:
       - checkout
       - node/install-packages:
-          pkg-manager: yarn
+          pkg-manager: yarn-berry
       - run: yarn build
       - run: yarn test
 
@@ -39,6 +39,6 @@ jobs:
     steps:
       - checkout
       - node/install-packages:
-          pkg-manager: yarn
+          pkg-manager: yarn-berry
       - run: yarn build
       - run: yarn semantic-release
diff --git a/.npmignore b/.npmignore
new file mode 100644
index 0000000..689ead8
--- /dev/null
+++ b/.npmignore
@@ -0,0 +1,11 @@
+/.circleci
+/.github
+/.yarn
+/.nvmrc
+/.prettierrc.js
+/.yarnrc.yml
+/jest.config.js
+/release.config.js
+
+tsconfig.json
+node_modules