diff --git a/modules/effects/src/effect_sources.ts b/modules/effects/src/effect_sources.ts
index 5d85587d18..97796dfc45 100644
--- a/modules/effects/src/effect_sources.ts
+++ b/modules/effects/src/effect_sources.ts
@@ -18,7 +18,6 @@ import { mergeEffects } from './effects_resolver';
 import {
   onIdentifyEffectsKey,
   onRunEffectsKey,
-  onRunEffectsFn,
   OnRunEffects,
   onInitEffects,
 } from './lifecycle_hooks';
@@ -30,7 +29,7 @@ export class EffectSources extends Subject<any> {
     super();
   }
 
-  addEffects(effectSourceInstance: any) {
+  addEffects(effectSourceInstance: any): void {
     this.next(effectSourceInstance);
 
     if (
@@ -91,9 +90,9 @@ function resolveEffectSource(
   };
 }
 
-function isOnRunEffects(sourceInstance: {
-  [onRunEffectsKey]?: onRunEffectsFn;
-}): sourceInstance is OnRunEffects {
+function isOnRunEffects(
+  sourceInstance: Partial<OnRunEffects>
+): sourceInstance is OnRunEffects {
   const source = getSourceForInstance(sourceInstance);
 
   return (
diff --git a/modules/effects/src/lifecycle_hooks.ts b/modules/effects/src/lifecycle_hooks.ts
index be86334021..ada4d08c83 100644
--- a/modules/effects/src/lifecycle_hooks.ts
+++ b/modules/effects/src/lifecycle_hooks.ts
@@ -37,10 +37,6 @@ export interface OnIdentifyEffects {
 export const onIdentifyEffectsKey: keyof OnIdentifyEffects =
   'ngrxOnIdentifyEffects';
 
-export type onRunEffectsFn = (
-  resolvedEffects$: Observable<EffectNotification>
-) => Observable<EffectNotification>;
-
 /**
  * @description
  * Interface to control the lifecycle of effects.
@@ -73,7 +69,9 @@ export interface OnRunEffects {
    * @description
    * Method to control the lifecycle of effects.
    */
-  ngrxOnRunEffects: onRunEffectsFn;
+  ngrxOnRunEffects(
+    resolvedEffects$: Observable<EffectNotification>
+  ): Observable<EffectNotification>;
 }
 
 export const onRunEffectsKey: keyof OnRunEffects = 'ngrxOnRunEffects';