diff --git a/src/effect.ts b/src/effect.ts
index 7aad9cb..ac7f896 100644
--- a/src/effect.ts
+++ b/src/effect.ts
@@ -9,7 +9,8 @@ type SourceValue<S> =
 
 export const effect = <S extends (Signal<any> | Events<any>)[]>(
   sources: [...S],
-  callback: (values: { [K in keyof S]: SourceValue<S[K]> }) => void
+  callback: (values: { [K in keyof S]: SourceValue<S[K]> }) => void,
+  { trigger }: { trigger?: boolean } = {}
 ): Effect => {
   const { use, dispose } = system()
 
@@ -42,6 +43,10 @@ export const effect = <S extends (Signal<any> | Events<any>)[]>(
     }
   })
 
+  if (trigger) {
+    updateValues()
+  }
+
   return {
     use,
     dispose
diff --git a/test/effect.test.ts b/test/effect.test.ts
index debbeb0..0daa1ab 100644
--- a/test/effect.test.ts
+++ b/test/effect.test.ts
@@ -63,4 +63,14 @@ describe('effect', () => {
     expect(mockSub).toHaveBeenCalledTimes(2)
     expect(mockDispose).toHaveBeenCalledTimes(1)
   })
+  it('triggers as expected', () => {
+    const exampleEvents = createEvents<{ something: number; else: string[] }>()
+    const exampleSignal = signal(() => 10)
+
+    const mockSub = mock(() => ({}))
+
+    effect([exampleEvents, exampleSignal], mockSub, { trigger: true })
+
+    expect(mockSub).toHaveBeenCalledTimes(1)
+  })
 })