diff --git a/.circleci/config.yml b/.circleci/config.yml
index e140409c4..1e22885ff 100644
--- a/.circleci/config.yml
+++ b/.circleci/config.yml
@@ -57,6 +57,7 @@ jobs:
           command: echo "//registry.npmjs.org/:_authToken=$NPM_TOKEN" >> ~/.npmrc
       - run: git config --global user.email circleci@circleci
       - run: git config --global user.name CircleCI
+      - run: npm run build:types
       - run:
           name: Publish package
           command: "./node_modules/.bin/lerna publish --message 'chore: release new versions' --exact --yes"
diff --git a/.gitignore b/.gitignore
index 1df5c5078..c0ec93709 100644
--- a/.gitignore
+++ b/.gitignore
@@ -20,6 +20,10 @@ yarn-error.log
 /build/
 /bundlesize/dist/
 
+## types
+*.d.ts
+!packages/*/types/*
+
 ## temp folders
 /.tmp/
 /coverage/
diff --git a/package.json b/package.json
index 4f19dcd20..3ee31dc1a 100644
--- a/package.json
+++ b/package.json
@@ -6,6 +6,8 @@
     "packages/*"
   ],
   "scripts": {
+    "build:docs": "wca analyze \"packages/tabs/**/*.js\"",
+    "build:types": "tsc -p tsconfig.build.types.json",
     "bundlesize": "rollup -c bundlesize/rollup.config.js && bundlesize",
     "dev-server": "es-dev-server",
     "format": "npm run format:eslint && npm run format:prettier",
@@ -16,6 +18,7 @@
     "lint:eslint": "eslint --ext .js,.html .",
     "lint:markdownlint": "git ls-files '*.md' | xargs markdownlint --ignore '**/CHANGELOG.md'",
     "lint:prettier": "prettier \"**/*.js\" --list-different || (echo '↑↑ these files are not prettier formatted ↑↑' && exit 1)",
+    "lint:types": "tsc",
     "lint:versions": "node ./scripts/lint-versions.js",
     "start": "npm run storybook",
     "storybook": "start-storybook -p 9001",
@@ -33,10 +36,11 @@
     "@open-wc/building-rollup": "^1.2.1",
     "@open-wc/demoing-storybook": "^2.0.2",
     "@open-wc/eslint-config": "^1.0.0",
-    "@open-wc/testing": "^2.5.0",
+    "@open-wc/testing": "^2.5.18",
     "@open-wc/testing-helpers": "^1.0.0",
     "@storybook/addon-a11y": "~5.0.0",
     "@web/test-runner": "^0.6.18",
+    "@types/chai-dom": "^0.0.8",
     "@webcomponents/webcomponentsjs": "^2.2.5",
     "babel-eslint": "^8.2.6",
     "babel-polyfill": "^6.26.0",
@@ -56,6 +60,8 @@
     "rimraf": "^2.6.3",
     "rollup": "^2.0.0",
     "sinon": "^7.2.2",
+    "typescript": "^3.8.3",
+    "web-component-analyzer": "^1.0.3",
     "webpack-merge": "^4.1.5",
     "whatwg-fetch": "^3.0.0"
   },
diff --git a/tsconfig.build.types.json b/tsconfig.build.types.json
new file mode 100644
index 000000000..eb0daa6a4
--- /dev/null
+++ b/tsconfig.build.types.json
@@ -0,0 +1,8 @@
+{
+  "extends": "./tsconfig.json",
+  "compilerOptions": {
+    "declaration": true,
+    "emitDeclarationOnly": true,
+    "noEmit": false
+  }
+}
diff --git a/tsconfig.json b/tsconfig.json
new file mode 100644
index 000000000..02514af21
--- /dev/null
+++ b/tsconfig.json
@@ -0,0 +1,24 @@
+{
+  "compilerOptions": {
+    "target": "esnext",
+    "module": "esnext",
+    "moduleResolution": "node",
+    "lib": ["es2017", "dom"],
+    "allowJs": true,
+    "checkJs": true,
+    "noEmit": true,
+    "strict": true,
+    "noImplicitThis": true,
+    "alwaysStrict": true,
+    "types": ["node", "mocha"],
+    "esModuleInterop": true
+  },
+  "include": ["packages/core/**/*.js", "packages/tabs/**/*.js"],
+  "exclude": [
+    "node_modules",
+    "**/node_modules/*",
+    "**/coverage/*",
+    "**/dist/**/*",
+    "packages/**/test-helpers"
+  ]
+}
diff --git a/yarn.lock b/yarn.lock
index 496fcb7a9..869c7b1d3 100644
--- a/yarn.lock
+++ b/yarn.lock
@@ -2413,11 +2413,16 @@
     "@open-wc/semantic-dom-diff" "^0.13.16"
     "@types/chai" "^4.1.7"
 
-"@open-wc/dedupe-mixin@^1.2.1", "@open-wc/dedupe-mixin@^1.2.17":
+"@open-wc/dedupe-mixin@^1.2.17":
   version "1.2.17"
   resolved "https://registry.yarnpkg.com/@open-wc/dedupe-mixin/-/dedupe-mixin-1.2.17.tgz#50fb903fc8785639487d7987caae45d7bba08ec7"
   integrity sha512-9A3WohqNxEloJa4y1DuBL5zH12cNRNW1vsrkiaLMnOGuQdhibs2XY1oliudsKpvIeNjDXRVRPUdIIzn65BypCw==
 
+"@open-wc/dedupe-mixin@^1.2.18":
+  version "1.2.18"
+  resolved "https://registry.yarnpkg.com/@open-wc/dedupe-mixin/-/dedupe-mixin-1.2.18.tgz#2a86672fb3558fe2a2e1c5587dbaa0b485567ef1"
+  integrity sha512-1HpblP5edeENi0SKms7B+PKYdxHMBIQpaf0nAgTVsZeYgM9OJ3r9nrK/0MOUBZODAOZ1quvO3wlpuljq2hZPWA==
+
 "@open-wc/demoing-storybook@^2.0.2":
   version "2.3.11"
   resolved "https://registry.yarnpkg.com/@open-wc/demoing-storybook/-/demoing-storybook-2.3.11.tgz#4c4887760591c6e58fb25852c92f0357c3445246"
@@ -2516,7 +2521,7 @@
     lit-element "^2.2.1"
     lit-html "^1.0.0"
 
-"@open-wc/testing@^2.5.0":
+"@open-wc/testing@^2.5.18":
   version "2.5.18"
   resolved "https://registry.yarnpkg.com/@open-wc/testing/-/testing-2.5.18.tgz#b05215535a22515fbd98183eface1c33fd804a5d"
   integrity sha512-poFIaGEsHseNEbAE/pGjzZGbSksxqsL4CRr+MSPUEotzhbVa3BzA3JzPHfn3FD1zVGlBcNEU0kFa0jj/Goc52w==
@@ -2807,6 +2812,13 @@
   resolved "https://registry.yarnpkg.com/@types/caniuse-api/-/caniuse-api-3.0.0.tgz#af31cc52062be0ab24583be072fd49b634dcc2fe"
   integrity sha512-wT1VfnScjAftZsvLYaefu/UuwYJdYBwD2JDL2OQd01plGmuAoir5V6HnVHgrfh7zEwcasoiyO2wQ+W58sNh2sw==
 
+"@types/chai-dom@^0.0.8":
+  version "0.0.8"
+  resolved "https://registry.yarnpkg.com/@types/chai-dom/-/chai-dom-0.0.8.tgz#832b68d78390c80030e64d8fd4990e514484e91d"
+  integrity sha512-F5vAuz2hp7VY+0UmkFLgTwyeHDddIw1c/JbAQZp2lgpZOd3ujlHFijWO4sHdo7sun9HrzwnSJlZfINdKrUwI+w==
+  dependencies:
+    "@types/chai" "*"
+
 "@types/chai-dom@^0.0.9":
   version "0.0.9"
   resolved "https://registry.yarnpkg.com/@types/chai-dom/-/chai-dom-0.0.9.tgz#77379354efec2568284ca355fff6a4f85f5a66f4"
@@ -6438,6 +6450,18 @@ fast-glob@^2.2.6:
     merge2 "^1.2.3"
     micromatch "^3.1.10"
 
+fast-glob@^3.1.0:
+  version "3.2.4"
+  resolved "https://registry.yarnpkg.com/fast-glob/-/fast-glob-3.2.4.tgz#d20aefbf99579383e7f3cc66529158c9b98554d3"
+  integrity sha512-kr/Oo6PX51265qeuCYsyGypiO5uJFgBS0jksyG7FUeCyQzNwYnzrNIMR1NXfkZXsMYXYLRAHgISHBz8gQcxKHQ==
+  dependencies:
+    "@nodelib/fs.stat" "^2.0.2"
+    "@nodelib/fs.walk" "^1.2.3"
+    glob-parent "^5.1.0"
+    merge2 "^1.3.0"
+    micromatch "^4.0.2"
+    picomatch "^2.2.1"
+
 fast-glob@^3.1.1:
   version "3.2.2"
   resolved "https://registry.yarnpkg.com/fast-glob/-/fast-glob-3.2.2.tgz#ade1a9d91148965d4bf7c51f72e1ca662d32e63d"
@@ -13026,6 +13050,11 @@ try-to-catch@^1.0.2:
   resolved "https://registry.yarnpkg.com/try-to-catch/-/try-to-catch-1.1.1.tgz#770162dd13b9a0e55da04db5b7f888956072038a"
   integrity sha512-ikUlS+/BcImLhNYyIgZcEmq4byc31QpC+46/6Jm5ECWkVFhf8SM2Fp/0pMVXPX6vk45SMCwrP4Taxucne8I0VA==
 
+ts-simple-type@~0.3.6:
+  version "0.3.7"
+  resolved "https://registry.yarnpkg.com/ts-simple-type/-/ts-simple-type-0.3.7.tgz#1e77222c3d90d7093f80a954e74c725fd99c911c"
+  integrity sha512-bDXWURwpDpe1mA5E9eldmI0Mpt9zGprhtN/ZTLOJjsAMyeMy1UT7WvGRQghYewIYBYxDZurChhe4DrsPbcCVrA==
+
 tsconfig-paths@^3.9.0:
   version "3.9.0"
   resolved "https://registry.yarnpkg.com/tsconfig-paths/-/tsconfig-paths-3.9.0.tgz#098547a6c4448807e8fcb8eae081064ee9a3c90b"
@@ -13127,10 +13156,10 @@ typedarray@^0.0.6:
   resolved "https://registry.yarnpkg.com/typedarray/-/typedarray-0.0.6.tgz#867ac74e3864187b1d3d47d996a78ec5c8830777"
   integrity sha1-hnrHTjhkGHsdPUfZlqeOxciDB3c=
 
-typescript@^3.6.4:
-  version "3.9.5"
-  resolved "https://registry.yarnpkg.com/typescript/-/typescript-3.9.5.tgz#586f0dba300cde8be52dd1ac4f7e1009c1b13f36"
-  integrity sha512-hSAifV3k+i6lEoCJ2k6R2Z/rp/H3+8sdmcn5NrS3/3kE7+RyZXm9aqvxWqjEXHAd8b0pShatpcdMTvEdvAJltQ==
+typescript@^3.5.3, typescript@^3.8.3:
+  version "3.9.6"
+  resolved "https://registry.yarnpkg.com/typescript/-/typescript-3.9.6.tgz#8f3e0198a34c3ae17091b35571d3afd31999365a"
+  integrity sha512-Pspx3oKAPJtjNwE92YS05HQoY7z2SFyOpHo9MqJor3BXAGNaPUs83CuVp9VISFkSjyRfiTpmKuAYGJB7S7hOxw==
 
 typical@^4.0.0:
   version "4.0.0"
@@ -13629,6 +13658,16 @@ wcwidth@^1.0.0, wcwidth@^1.0.1:
   dependencies:
     defaults "^1.0.3"
 
+web-component-analyzer@^1.0.3:
+  version "1.0.3"
+  resolved "https://registry.yarnpkg.com/web-component-analyzer/-/web-component-analyzer-1.0.3.tgz#da73dff15d6a8f4864311664476f0f436274e97d"
+  integrity sha512-QA6GVVJrKRPHLVqPv4evY0H+du1yY+E1q8c82bdY5e10+pWsRfeYA+Hsh2r8yl1EGQVC55SeV3tGvJ6+CxaH/Q==
+  dependencies:
+    fast-glob "^3.1.0"
+    ts-simple-type "~0.3.6"
+    typescript "^3.5.3"
+    yargs "^15.0.2"
+
 web-namespaces@^1.0.0, web-namespaces@^1.1.2:
   version "1.1.4"
   resolved "https://registry.yarnpkg.com/web-namespaces/-/web-namespaces-1.1.4.tgz#bc98a3de60dadd7faefc403d1076d529f5e030ec"