diff --git a/src/components/pull-request-list/pull-request-list.spec.ts b/src/components/pull-request-list/pull-request-list.spec.ts
index d1a7f14f..9525d220 100644
--- a/src/components/pull-request-list/pull-request-list.spec.ts
+++ b/src/components/pull-request-list/pull-request-list.spec.ts
@@ -7,7 +7,7 @@ import PullRequestLine from '../ui/pull-request-line/pull-request-line.vue'
 import type { Mocks, Wrapper } from '../../test-utils.ts'
 import { buildRepositoriesQuery } from '../../services/graphql/query-builder.ts'
 import { extractHttp as extractPullRequest, type GDPullRequest } from '../../services/pull-request/pull-request.ts'
-import type { pullRequestNotifications } from '../../services/pull-request-notifications/pull-request-notifications'
+import type { pullRequestNotifications } from '../../services/pull-request-notifications/pull-request-notifications.ts'
 import type { buildUserService } from '../../services/user/user'
 
 type Dependencies = {
diff --git a/src/components/pull-request-list/pull-request-list.vue b/src/components/pull-request-list/pull-request-list.vue
index 5e4b61eb..69e61dfe 100644
--- a/src/components/pull-request-list/pull-request-list.vue
+++ b/src/components/pull-request-list/pull-request-list.vue
@@ -38,7 +38,7 @@ import {
 import { buildUserService } from '../../services/user/user'
 import { useRepositoryStore } from '../../stores/repositories/repositories'
 import { computed, inject, ref } from 'vue'
-import { pullRequestNotifications as defaultPullRequestNotifications } from '../../services/pull-request-notifications/pull-request-notifications'
+import { pullRequestNotifications as defaultPullRequestNotifications } from '../../services/pull-request-notifications/pull-request-notifications.ts'
 import { NO_USER } from '../../services/session/session.ts'
 
 const pullRequestListFragment = `${pullRequestFragment}
diff --git a/src/services/pull-request-notifications/pull-request-notifications.spec.js b/src/services/pull-request-notifications/pull-request-notifications.spec.ts
similarity index 58%
rename from src/services/pull-request-notifications/pull-request-notifications.spec.js
rename to src/services/pull-request-notifications/pull-request-notifications.spec.ts
index 2f3e3845..d4213034 100644
--- a/src/services/pull-request-notifications/pull-request-notifications.spec.js
+++ b/src/services/pull-request-notifications/pull-request-notifications.spec.ts
@@ -1,69 +1,68 @@
-import { pullRequestNotifications } from './pull-request-notifications'
+import { type Dependencies, pullRequestNotifications } from './pull-request-notifications.ts'
 import { beforeEach, describe, expect, it, vitest } from 'vitest'
+import type { Mocks } from '../../test-utils.ts'
 
 describe('Pull request notification service', () => {
-	let stubs
+	let pullRequestNotification: ReturnType<typeof pullRequestNotifications>
+	let stubs: Mocks<Dependencies>
 	beforeEach(() => {
-		const notify = vitest.fn()
 		stubs = {
 			notificationApi: {
-				notify
-			},
-			notify
+				notify: vitest.fn(),
+				requestNotifications: vitest.fn()
+			}
 		}
+
+		pullRequestNotification = pullRequestNotifications(stubs)
 	})
 
 	it('should not send notifications when there is no new pull request', () => {
-		const pullRequestNotification = pullRequestNotifications(stubs)
-
 		pullRequestNotification.newList([])
 
-		expect(stubs.notify).not.toHaveBeenCalled()
+		expect(stubs.notificationApi.notify).not.toHaveBeenCalled()
 	})
 
 	it('should send notifications when there is a new pull request', () => {
-		const pullRequestNotification = pullRequestNotifications(stubs)
-
 		pullRequestNotification.newList([{ title: 'Test pull request', url: '/a/random/url' }])
 
-		expect(stubs.notify).toHaveBeenCalledWith('A new pull request was opened: Test pull request')
+		expect(stubs.notificationApi.notify).toHaveBeenCalledWith('A new pull request was opened: Test pull request')
 	})
 
 	it('should send notifications when there is multiple new pull requests', () => {
-		const pullRequestNotification = pullRequestNotifications(stubs)
-
 		pullRequestNotification.newList([
 			{ title: 'Test pull request', url: '/a/random/url' },
 			{ title: 'Another test pull request', url: '/a/random/url' }
 		])
 
-		expect(stubs.notify).toHaveBeenCalledWith('2 new pull requests were opened')
+		expect(stubs.notificationApi.notify).toHaveBeenCalledWith('2 new pull requests were opened')
 	})
 
 	it('should send notifications only for new pull requests', () => {
-		const pullRequestNotification = pullRequestNotifications(stubs)
 		pullRequestNotification.newList([{ title: 'Test pull request', url: '/a/random/url' }])
-		stubs.notify.mockClear()
+		stubs.notificationApi.notify.mockClear()
 
 		pullRequestNotification.newList([
 			{ title: 'Test pull request', url: '/a/random/url' },
 			{ title: 'Another test pull request', url: '/a/random/url' }
 		])
 
-		expect(stubs.notify).toHaveBeenCalledWith('A new pull request was opened: Another test pull request')
+		expect(stubs.notificationApi.notify).toHaveBeenCalledWith(
+			'A new pull request was opened: Another test pull request'
+		)
 	})
 
 	it('should keep already notified pull request', () => {
-		const pullRequestNotification = pullRequestNotifications(stubs)
 		pullRequestNotification.newList([{ title: 'Test pull request', url: '/a/random/url' }])
 		pullRequestNotification.newList([])
-		stubs.notify.mockClear()
+		stubs.notificationApi.notify.mockClear()
 
 		pullRequestNotification.newList([
 			{ title: 'Test pull request', url: '/a/random/url' },
 			{ title: 'Another test pull request', url: '/a/random/url' }
 		])
 
-		expect(stubs.notify).toHaveBeenCalledWith('A new pull request was opened: Another test pull request')
+		expect(stubs.notificationApi.notify).toHaveBeenCalledWith(
+			'A new pull request was opened: Another test pull request'
+		)
 	})
 })
diff --git a/src/services/pull-request-notifications/pull-request-notifications.js b/src/services/pull-request-notifications/pull-request-notifications.ts
similarity index 62%
rename from src/services/pull-request-notifications/pull-request-notifications.js
rename to src/services/pull-request-notifications/pull-request-notifications.ts
index ff656468..ef1a5ff2 100644
--- a/src/services/pull-request-notifications/pull-request-notifications.js
+++ b/src/services/pull-request-notifications/pull-request-notifications.ts
@@ -1,10 +1,12 @@
 import notificationService from '../notifications/notification'
 
+type PullRequest = { title: string; url: string }
 const defaults = { notificationApi: notificationService }
-const pullRequestNotifications = ({ notificationApi } = defaults) => {
-	let alreadyNotified = []
+export type Dependencies = { notificationApi: typeof notificationService }
+const pullRequestNotifications = ({ notificationApi }: Dependencies = defaults) => {
+	let alreadyNotified: PullRequest[] = []
 
-	const newList = (pullRequests) => {
+	const newList = (pullRequests: PullRequest[]) => {
 		const prToNotify = pullRequests.filter(
 			({ title }) => !alreadyNotified.find((notifiedPr) => notifiedPr.title === title)
 		)
@@ -15,8 +17,8 @@ const pullRequestNotifications = ({ notificationApi } = defaults) => {
 		}
 	}
 
-	const formatNotificationMessage = (prToNotify) => {
-		if (prToNotify.length === 1) {
+	const formatNotificationMessage = (prToNotify: PullRequest[]) => {
+		if (prToNotify.length === 1 && prToNotify[0]) {
 			const [{ title }] = prToNotify
 			return `A new pull request was opened: ${title}`
 		} else {