diff --git a/.flowconfig b/.flowconfig
index 38f7435d5..a646597fd 100644
--- a/.flowconfig
+++ b/.flowconfig
@@ -1,5 +1,5 @@
 [version]
-0.55.0
+0.59.0
 
 [ignore]
 .*test
diff --git a/lib/GridItem.jsx b/lib/GridItem.jsx
index 04f340888..99e97abd1 100644
--- a/lib/GridItem.jsx
+++ b/lib/GridItem.jsx
@@ -81,25 +81,25 @@ export default class GridItem extends React.Component<Props, State> {
     h: PropTypes.number.isRequired,
 
     // All optional
-    minW: function (props, propName) {
+    minW: function (props: Props, propName: string) {
       const value = props[propName];
       if (typeof value !== 'number') return new Error('minWidth not Number');
       if (value > props.w || value > props.maxW) return new Error('minWidth larger than item width/maxWidth');
     },
 
-    maxW: function (props, propName) {
+    maxW: function (props: Props, propName: string) {
       const value = props[propName];
       if (typeof value !== 'number') return new Error('maxWidth not Number');
       if (value < props.w || value < props.minW) return new Error('maxWidth smaller than item width/minWidth');
     },
 
-    minH: function (props, propName) {
+    minH: function (props: Props, propName: string) {
       const value = props[propName];
       if (typeof value !== 'number') return new Error('minHeight not Number');
       if (value > props.h || value > props.maxH) return new Error('minHeight larger than item height/maxHeight');
     },
 
-    maxH: function (props, propName) {
+    maxH: function (props: Props, propName: string) {
       const value = props[propName];
       if (typeof value !== 'number') return new Error('maxHeight not Number');
       if (value < props.h || value < props.minH) return new Error('maxHeight smaller than item height/minHeight');
diff --git a/lib/ReactGridLayout.jsx b/lib/ReactGridLayout.jsx
index 660d55733..65c29a02e 100644
--- a/lib/ReactGridLayout.jsx
+++ b/lib/ReactGridLayout.jsx
@@ -32,7 +32,7 @@ export type Props = {
   compactType: ?('horizontal' | 'vertical'),
   layout: Layout,
   margin: [number, number],
-  containerPadding: [number, number],
+  containerPadding: [number, number] | null,
   rowHeight: number,
   maxRows: number,
   isDraggable: boolean,
@@ -83,7 +83,7 @@ export default class ReactGridLayout extends React.Component<Props, State> {
     draggableHandle: PropTypes.string,
 
     // Deprecated
-    verticalCompact: function(props) {
+    verticalCompact: function(props: Props) {
       if (props.verticalCompact === false && process.env.NODE_ENV !== 'production') {
         console.warn( // eslint-disable-line no-console
           '`verticalCompact` on <ReactGridLayout> is deprecated and will be removed soon. ' +
@@ -95,7 +95,7 @@ export default class ReactGridLayout extends React.Component<Props, State> {
 
     // layout is an array of object with the format:
     // {x: Number, y: Number, w: Number, h: Number, i: String}
-    layout: function (props) {
+    layout: function (props: Props) {
       var layout = props.layout;
       // I hope you're setting the data-grid property on the grid items
       if (layout === undefined) return;
@@ -155,7 +155,7 @@ export default class ReactGridLayout extends React.Component<Props, State> {
     //
 
     // Children must not have duplicate keys.
-    children: function (props, propName, _componentName) {
+    children: function (props: Props, propName: string) {
       var children = props[propName];
 
       // Check children keys for duplicates. Throw if found.
@@ -173,6 +173,10 @@ export default class ReactGridLayout extends React.Component<Props, State> {
     autoSize: true,
     cols: 12,
     className: '',
+    style: {},
+    draggableHandle: '',
+    draggableCancel: '',
+    containerPadding: null,
     rowHeight: 150,
     maxRows: Infinity, // infinite vertical growth
     layout: [],
diff --git a/lib/ResponsiveReactGridLayout.jsx b/lib/ResponsiveReactGridLayout.jsx
index 6624b5987..37f2925ff 100644
--- a/lib/ResponsiveReactGridLayout.jsx
+++ b/lib/ResponsiveReactGridLayout.jsx
@@ -32,7 +32,7 @@ type Props<Breakpoint: string = string> = {
   onBreakpointChange: (Breakpoint, cols: number) => void,
   onLayoutChange: (Layout, {[key: Breakpoint]: Layout}) => void,
   onWidthChange:
-    (containerWidth: number, margin: [number, number], cols: number, containerPadding: [number, number]) => void
+    (containerWidth: number, margin: [number, number], cols: number, containerPadding: [number, number] | null) => void
 };
 
 export default class ResponsiveReactGridLayout extends React.Component<Props<>, State> {
@@ -57,7 +57,7 @@ export default class ResponsiveReactGridLayout extends React.Component<Props<>,
 
     // layouts is an object mapping breakpoints to layouts.
     // e.g. {lg: Layout, md: Layout, ...}
-    layouts(props, propName) {
+    layouts(props: Props<>, propName: string) {
       if (type(props[propName]) !== '[object Object]') {
         throw new Error('Layout property must be an object. Received: ' + type(props[propName]));
       }