diff --git a/types/retinajs/index.d.ts b/types/retinajs/index.d.ts
new file mode 100644
index 0000000000..58b3e3b653
--- /dev/null
+++ b/types/retinajs/index.d.ts
@@ -0,0 +1,42 @@
+export = retinajs.retina;
+
+export as namespace retinajs;
+
+declare namespace retinajs {
+  var hasWindow: boolean;
+
+  var environment: number;
+
+  var srcReplace: RegExp;
+
+  var inlineReplace: RegExp;
+
+  var selector: string;
+
+  var processedAttr: string;
+
+  var processedAttr: string;
+
+  function arrayify(object: any): HTMLImageElement[];
+
+  function chooseCap(cap: number | string): number;
+
+  function forceOriginalDimensions(image: HTMLImageElement): HTMLImageElement;
+
+  function setSourceIfAvailable(
+    image: HTMLImageElement,
+    retinaURL: string
+  ): void;
+
+  function dynamicSwapImage(image: HTMLImageElement, src: string): void;
+
+  function manualSwapImage(image: HTMLImageElement, hdsrc: string): void;
+
+  function getImages(images: HTMLImageElement[] | null): HTMLImageElement[];
+
+  function cleanBgImg(img: HTMLImageElement): HTMLImageElement;
+
+  function retina(): void;
+
+  function retina(images: any): void;
+}