diff --git a/leaflet.gridlayer.googlemutant/index.d.ts b/leaflet.gridlayer.googlemutant/index.d.ts
new file mode 100644
index 0000000000..2f62268fcd
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+++ b/leaflet.gridlayer.googlemutant/index.d.ts
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+// Type definitions for leaflet.gridlayer.googlemutant 0.4
+// Project: https://gitlab.com/IvanSanchez/Leaflet.GridLayer.GoogleMutant#README
+// Definitions by: Ernest Rhinozeros <https://github.com/ernest-rhinozeros>
+// Definitions: https://github.com/DefinitelyTyped/DefinitelyTyped
+
+/// <reference types="leaflet" />
+
+declare namespace L.GridLayer {
+    export interface GoogleMutant extends L.GridLayer {
+        setElementSize(e: HTMLElement, size: L.Point): void ;
+    }
+
+    export type GoogleMutantType = 'roadmap' | 'satellite' | 'terrain' | 'hybrid';
+
+    export interface GoogleMutantStyler {
+        hue?: string;
+        lightness?: number;
+        saturation?: number;
+        gamma?: number;
+        invert_lightness?: boolean;
+        visibility?: string;
+        color?: string;
+        weight?: number;
+    }
+
+    /**
+     * Google's map style.
+     *
+     * https://developers.google.com/maps/documentation/javascript/style-reference
+     */
+    export interface GoogleMutantStyle {
+
+        /**
+         * https://developers.google.com/maps/documentation/javascript/style-reference#style-features
+         */
+        featureType?: string;
+
+        /**
+         * https://developers.google.com/maps/documentation/javascript/style-reference#style-elements
+         */
+        elementType?: string;
+
+        /**
+         * https://developers.google.com/maps/documentation/javascript/style-reference#stylers
+         */
+        stylers?: GoogleMutantStyler[];
+    }
+
+    export interface GoogleMutantOptions extends L.TileLayerOptions {
+        minZoom?: number;
+        maxZoom?: number;
+        maxNativeZoom?: number;
+        tileSize?: number | Point;
+        subdomains?: string | Array<string>;
+        errorTileUrl?: string;
+
+        /**
+         * The mutant container will add its own attribution anyways.
+         */
+        attribution?: string;
+
+        opacity?: number;
+        continuousWorld?: boolean,
+        noWrap?: boolean;
+
+        /**
+         * Google's map type. 'hybrid' is not really supported.
+         */
+        type?: GoogleMutantType;
+
+        /**
+         * Google's map styles.
+         */
+        styles?: GoogleMutantStyle[]
+    }
+
+    export function googleMutant(options?: GoogleMutantOptions): GoogleMutant;
+}
diff --git a/leaflet.gridlayer.googlemutant/leaflet.gridlayer.googlemutant-tests.ts b/leaflet.gridlayer.googlemutant/leaflet.gridlayer.googlemutant-tests.ts
new file mode 100644
index 0000000000..53e8dc3e1c
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+++ b/leaflet.gridlayer.googlemutant/leaflet.gridlayer.googlemutant-tests.ts
@@ -0,0 +1,13 @@
+let map = L.map('foo');
+
+let roads = L.GridLayer.googleMutant({
+    type: 'roadmap'
+}).addTo(map);
+
+let styled = L.GridLayer.googleMutant({
+    type: 'satellite',
+    styles: [
+        { elementType: 'labels', stylers: [ { visibility: 'off' } ] },
+        { featureType: 'water' , stylers: [ { color: '#444444'  } ] }
+    ]
+}).addTo(map);
diff --git a/leaflet.gridlayer.googlemutant/tsconfig.json b/leaflet.gridlayer.googlemutant/tsconfig.json
new file mode 100644
index 0000000000..2e8651b58b
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+++ b/leaflet.gridlayer.googlemutant/tsconfig.json
@@ -0,0 +1,20 @@
+{
+    "compilerOptions": {
+        "module": "commonjs",
+        "target": "es6",
+        "noImplicitAny": true,
+        "noImplicitThis": true,
+        "strictNullChecks": true,
+        "baseUrl": "../",
+        "typeRoots": [
+            "../"
+        ],
+        "types": [],
+        "noEmit": true,
+        "forceConsistentCasingInFileNames": true
+    },
+    "files": [
+        "index.d.ts",
+        "leaflet.gridlayer.googlemutant-tests.ts"
+    ]
+}
diff --git a/leaflet.gridlayer.googlemutant/tslint.json b/leaflet.gridlayer.googlemutant/tslint.json
new file mode 100644
index 0000000000..377cc837d4
--- /dev/null
+++ b/leaflet.gridlayer.googlemutant/tslint.json
@@ -0,0 +1 @@
+{ "extends": "../tslint.json" }