diff --git a/.travis.yml b/.travis.yml
index 459e059..e56c63d 100644
--- a/.travis.yml
+++ b/.travis.yml
@@ -7,3 +7,4 @@ script:
   - ./node_modules/.bin/lerna bootstrap --hoist
   - npm run build
   - npm run lint
+  - npm run flow
diff --git a/examples/counter/package.json b/examples/counter/package.json
index c3e3513..d5d1752 100644
--- a/examples/counter/package.json
+++ b/examples/counter/package.json
@@ -16,5 +16,8 @@
     "build": "react-scripts build",
     "test": "react-scripts test --env=jsdom",
     "eject": "react-scripts eject"
+  },
+  "devDependencies": {
+    "draft-js": "^0.10.5"
   }
 }
diff --git a/examples/mentions-example/package.json b/examples/mentions-example/package.json
index 71bf19a..913ccee 100644
--- a/examples/mentions-example/package.json
+++ b/examples/mentions-example/package.json
@@ -18,5 +18,8 @@
     "build": "react-scripts build",
     "test": "react-scripts test --env=jsdom",
     "eject": "react-scripts eject"
+  },
+  "devDependencies": {
+    "draft-js": "^0.10.5"
   }
 }
diff --git a/lerna.json b/lerna.json
index fad86ab..0a8fa7b 100644
--- a/lerna.json
+++ b/lerna.json
@@ -4,5 +4,6 @@
     "examples/*",
     "packages/*"
   ],
+  "nohoist": ["**/draft-js"],
   "version": "0.1.5"
 }
diff --git a/packages/atomic-block/package.json b/packages/atomic-block/package.json
index 92995ed..218f663 100644
--- a/packages/atomic-block/package.json
+++ b/packages/atomic-block/package.json
@@ -14,7 +14,7 @@
     "build": "./node_modules/.bin/rollup -c",
     "start": "./node_modules/.bin/rollup -c -w",
     "prepare": "yarn run build",
-    "flow": "./node_modules/.bin/flow",
+    "flow": "./node_modules/.bin/flow check",
     "predeploy": "cd example && yarn install && yarn run build",
     "deploy": "gh-pages -d example/build"
   },
diff --git a/packages/atomic-block/src/index.js b/packages/atomic-block/src/index.js
index 3d48b8d..c2f5e43 100644
--- a/packages/atomic-block/src/index.js
+++ b/packages/atomic-block/src/index.js
@@ -1,6 +1,7 @@
 // @flow
 
 import React, { Component } from 'react'
+import type { Node } from 'react'
 import { withPluginContext, constants } from '@djsp/core'
 import type { PluginProps } from '@djsp/core'
 import { ContentBlock, EditorState, Modifier, SelectionState } from 'draft-js'
@@ -13,7 +14,7 @@ const _BlockChildren = ({
   editorState,
   setEditorState,
   ...props
-}: Object) => {
+}: Object): Node => {
   const blockKey = props.block.getKey()
   const { children, focusBlock } = props.blockProps
   const selection = editorState.getSelection()
@@ -43,7 +44,7 @@ type Props = PluginProps & {
 // Set selection of editor to next/previous block
 const setSelection = (
   editorState: EditorState,
-  setEditorState: EditorState,
+  setEditorState: (editorState: EditorState) => void,
   newActiveBlock: ContentBlock
 ): void => {
   // TODO verify that always a key-0-0 exists
@@ -91,7 +92,10 @@ class AtomicBlockPlugin extends Component<Props> {
     this.unregister()
   }
 
-  handleKeyCommand = (command, editorState) => {
+  handleKeyCommand = (
+    command: string,
+    editorState: EditorState
+  ): DraftHandleValue => {
     const { setEditorState } = this.props
 
     let contentState = editorState.getCurrentContent()
@@ -189,7 +193,10 @@ class AtomicBlockPlugin extends Component<Props> {
     )
   }
 
-  handleReturn = (event, editorState) => {
+  handleReturn = (
+    event: SyntheticKeyboardEvent<*>,
+    editorState: EditorState
+  ): DraftHandleValue => {
     const { setEditorState } = this.props
     const selection = editorState.getSelection()
 
@@ -205,7 +212,7 @@ class AtomicBlockPlugin extends Component<Props> {
     return constants.NOT_HANDLED
   }
 
-  blockRendererFn = block => {
+  blockRendererFn = (block: ContentBlock): ?Object => {
     const { type, children, editorState } = this.props
 
     const content = editorState.getCurrentContent()
diff --git a/packages/autocomplete/package.json b/packages/autocomplete/package.json
index 3b22b4b..6d5de59 100644
--- a/packages/autocomplete/package.json
+++ b/packages/autocomplete/package.json
@@ -12,7 +12,7 @@
     "test": "cross-env CI=1 react-scripts test --env=jsdom",
     "test:watch": "react-scripts test --env=jsdom",
     "build": "./node_modules/.bin/rollup -c",
-    "flow": "./node_modules/.bin/flow",
+    "flow": "./node_modules/.bin/flow check",
     "start": "./node_modules/.bin/rollup -c -w",
     "prepare": "yarn run build",
     "predeploy": "cd example && yarn install && yarn run build",
diff --git a/packages/block-type-toggle/package.json b/packages/block-type-toggle/package.json
index 6035162..0761dc4 100644
--- a/packages/block-type-toggle/package.json
+++ b/packages/block-type-toggle/package.json
@@ -13,7 +13,7 @@
     "test:watch": "react-scripts test --env=jsdom",
     "build": "./node_modules/.bin/rollup -c",
     "start": "./node_modules/.bin/rollup -c -w",
-    "flow": "./node_modules/.bin/flow",
+    "flow": "./node_modules/.bin/flow check",
     "prepare": "yarn run build",
     "predeploy": "cd example && yarn install && yarn run build",
     "deploy": "gh-pages -d example/build"
diff --git a/packages/core/package.json b/packages/core/package.json
index 35a579e..741eb39 100644
--- a/packages/core/package.json
+++ b/packages/core/package.json
@@ -14,7 +14,7 @@
     "build": "rimraf dist && ./node_modules/.bin/rollup -c && yarn build:flow",
     "build:flow": "./node_modules/.bin/flow-copy-source -v -i '**/__tests__/**' src dist",
     "start": "./node_modules/.bin/rollup -c -w",
-    "flow": "./node_modules/.bin/flow",
+    "flow": "./node_modules/.bin/flow check",
     "prepare": "yarn run build && yarn build:flow",
     "predeploy": "cd example && yarn install && yarn run build",
     "deploy": "gh-pages -d example/build"
diff --git a/packages/inline-style-toggle/package.json b/packages/inline-style-toggle/package.json
index c8d32b2..18de847 100644
--- a/packages/inline-style-toggle/package.json
+++ b/packages/inline-style-toggle/package.json
@@ -10,7 +10,7 @@
   "jsnext:main": "dist/index.es.js",
   "scripts": {
     "test": "cross-env CI=1 react-scripts test --env=jsdom",
-    "flow": "./node_modules/.bin/flow",
+    "flow": "./node_modules/.bin/flow check",
     "test:watch": "react-scripts test --env=jsdom",
     "build": "./node_modules/.bin/rollup -c",
     "start": "./node_modules/.bin/rollup -c -w",
diff --git a/packages/utils/package.json b/packages/utils/package.json
index fa051fe..517290c 100644
--- a/packages/utils/package.json
+++ b/packages/utils/package.json
@@ -11,7 +11,7 @@
   "scripts": {
     "test": "cross-env CI=1 react-scripts test --env=jsdom",
     "test:watch": "react-scripts test --env=jsdom",
-    "flow": "./node_modules/.bin/flow",
+    "flow": "./node_modules/.bin/flow check",
     "build": "./node_modules/.bin/rollup -c",
     "start": "./node_modules/.bin/rollup -c -w",
     "prepare": "yarn run build",