diff --git a/README.md b/README.md
index 7842931..d30a371 100644
--- a/README.md
+++ b/README.md
@@ -5,8 +5,9 @@ ReactRelayNetworkLayer (for Relay Classic)
 [![Travis](https://img.shields.io/travis/nodkz/react-relay-network-layer.svg?maxAge=2592000)](https://travis-ci.org/nodkz/react-relay-network-layer)
 [![Commitizen friendly](https://img.shields.io/badge/commitizen-friendly-brightgreen.svg)](http://commitizen.github.io/cz-cli/)
 [![semantic-release](https://img.shields.io/badge/%20%20%F0%9F%93%A6%F0%9F%9A%80-semantic--release-e10079.svg)](https://github.com/semantic-release/semantic-release)
+![FlowType compatible](https://img.shields.io/badge/flowtype-compatible-brightgreen.svg)
 
-#### Currently this library supports **Relay classic** and compat mode. If you need **Relay Modern**, please subscribe on [issue #50](https://github.com/nodkz/react-relay-network-layer/issues/50). I'm not fulltime in OSS, so it will take some time. Thanks for patience. 
+#### Currently this library supports **Relay classic** and compat mode. If you need **Relay Modern**, please subscribe on [issue #50](https://github.com/nodkz/react-relay-network-layer/issues/50). I'm not fulltime in OSS, so it will take some time. Thanks for patience.
 
 The `ReactRelayNetworkLayer` is a [Relay Network Layer](https://facebook.github.io/relay/docs/guides-network-layer.html)
 with various middlewares which can manipulate requests/responses on the fly (change auth headers, request url or perform some fallback if request fails), batch several relay request by timeout into one http request.
diff --git a/package.json b/package.json
index 565db03..fdc5813 100644
--- a/package.json
+++ b/package.json
@@ -66,9 +66,10 @@
     ]
   },
   "scripts": {
-    "build": "npm run build-lib && npm run build-es",
+    "build": "npm run build-lib && npm run build-es && npm run build-flow",
     "build-lib": "rimraf lib && BABEL_ENV=lib babel src --ignore __tests__,__mocks__ -d lib",
     "build-es": "rimraf es && BABEL_ENV=es babel src --ignore __tests__,__mocks__ -d es",
+    "build-flow": "find ./src -name '*.js' -not -path '*/__*' | while read filepath; do cp $filepath `echo $filepath | sed 's/\\/src\\//\\/lib\\//g'`.flow; done",
     "lint": "eslint src test *.js",
     "coverage": "jest --coverage --maxWorkers 2",
     "watch": "jest --watch",