diff --git a/packages/core/src/components/loading-controller/loading-controller.tsx b/packages/core/src/components/loading-controller/loading-controller.tsx
index fa9500c0fd..21d781b4b1 100644
--- a/packages/core/src/components/loading-controller/loading-controller.tsx
+++ b/packages/core/src/components/loading-controller/loading-controller.tsx
@@ -45,7 +45,7 @@ export class LoadingController implements OverlayController {
    * Get the most recently opened loading overlay.
    */
   @Method()
-  getTop() {
+  getTop(): HTMLIonLoadingElement {
     return getTopOverlay(this.loadings);
   }
 }
diff --git a/packages/core/src/components/modal-controller/modal-controller.tsx b/packages/core/src/components/modal-controller/modal-controller.tsx
index 8a6cf4602f..6b039ebb31 100644
--- a/packages/core/src/components/modal-controller/modal-controller.tsx
+++ b/packages/core/src/components/modal-controller/modal-controller.tsx
@@ -45,7 +45,7 @@ export class ModalController implements OverlayController {
    * Get the most recently opened modal overlay.
    */
   @Method()
-  getTop() {
+  getTop(): HTMLIonModalElement {
     return getTopOverlay(this.modals);
   }
 }
diff --git a/packages/core/src/utils/overlays.ts b/packages/core/src/utils/overlays.ts
index 87f1b91422..89265443a6 100644
--- a/packages/core/src/utils/overlays.ts
+++ b/packages/core/src/utils/overlays.ts
@@ -2,14 +2,14 @@
 let lastId = 1;
 
 /**
- * Make all properties in T readonly
+ * Convert an interface where all the properties are optional to mandatory.
  */
-export type PropDescriptions<K extends string> = {
+export type Requires<K extends string> = {
   [P in K]: any;
 }
 
-
-export function createOverlay<T extends HTMLIonOverlayElement & PropDescriptions<keyof B>, B>
+export function createOverlay
+<T extends HTMLIonOverlayElement & Requires<keyof B>, B>
 (tagName: string, opts: B): Promise<T> {
   // create ionic's wrapping ion-alert component
   const element = document.createElement(tagName) as T;
@@ -52,7 +52,7 @@ export function getHighestId(overlays: OverlayMap) {
 }
 
 export function removeLastOverlay(overlays: OverlayMap) {
-  const toRemove = getTopOverlay(overlays) as any;
+  const toRemove = getTopOverlay(overlays);
   return toRemove ? toRemove.dismiss() : Promise.resolve();
 }