diff --git a/.env.example b/.env.example
index 92650db..2e0ac7f 100644
--- a/.env.example
+++ b/.env.example
@@ -1,4 +1,9 @@
+# Set to "1" for true
+APNS_IS_PRODUCTION=
+
 APNS_KEY_ID=
 APNS_TEAM_ID=
 APNS_BUNDLE_ID=
-APNS_KEY_PATH=
+
+# base64-encoded APNs private key
+APNS_PRIVATE_KEY=
diff --git a/src/services/NotificationService.ts b/src/services/NotificationService.ts
index 6fee796..c562986 100644
--- a/src/services/NotificationService.ts
+++ b/src/services/NotificationService.ts
@@ -18,7 +18,7 @@ interface APNsUrl {
 }
 
 export class NotificationService {
-  public readonly secondsThresholdForNotificationToFire = 300;
+  public readonly secondsThresholdForNotificationToFire = 180;
 
   private apnsToken: string | undefined = undefined;
 
@@ -52,9 +52,10 @@ export class NotificationService {
 
     const keyId = process.env.APNS_KEY_ID;
     const teamId = process.env.APNS_TEAM_ID;
-    const privateKeyPath = process.env.APNS_KEY_PATH;
-    if (!privateKeyPath) return;
-    const privateKey = fs.readFileSync(privateKeyPath);
+
+    const privateKeyBase64 = process.env.APNS_PRIVATE_KEY;
+    if (!privateKeyBase64) return;
+    const privateKey = Buffer.from(privateKeyBase64, 'base64').toString('utf-8');
 
     const tokenHeader = {
       alg: "ES256",
@@ -154,9 +155,9 @@ export class NotificationService {
     const devBaseUrl = "https://api.development.push.apple.com"
     const prodBaseUrl = "https://api.push.apple.com"
 
-    let hostToUse = prodBaseUrl;
-    if (process.env.NODE_ENV !== "production") {
-      hostToUse = devBaseUrl;
+    let hostToUse = devBaseUrl;
+    if (process.env.APNS_IS_PRODUCTION === "1") {
+      hostToUse = prodBaseUrl;
     }
 
     const path = "/3/device/" + deviceId;
diff --git a/test/services/NotificationServiceTests.test.ts b/test/services/NotificationServiceTests.test.ts
index 9ef66c6..7f3cfcf 100644
--- a/test/services/NotificationServiceTests.test.ts
+++ b/test/services/NotificationServiceTests.test.ts
@@ -1,21 +1,14 @@
 import { beforeEach, describe, expect, it, jest } from "@jest/globals";
 import { NotificationService } from "../../src/services/NotificationService";
 import { UnoptimizedInMemoryRepository } from "../../src/repositories/UnoptimizedInMemoryRepository";
-import fs from "fs";
 import http2 from "http2";
 import { IEta, IShuttle, IStop } from "../../src/entities/entities";
 import { addMockShuttleToRepository, addMockStopToRepository } from "../testHelpers/repositorySetupHelpers";
 import EventEmitter = require("node:events");
 
-jest.mock("fs");
 jest.mock("http2");
 
-const sampleKey = `-----BEGIN PRIVATE KEY-----
-MIGTAgEAMBMGByqGSM49AgEGCCqGSM49AwEHBHkwdwIBAQQgsrmSAZIagOfCP8sB
-Wi2CBXG1Oo7v1bispIZCwIr4RDegCgYIKoZIzj0DAQehRANCAATZHxV2wQJLMBq+
-ya+yfGi3g2ZUv6hrfe+j08ytekPHjXS0qzJoVELzKHa6EL9YAoZDXBtB6h+fGhXe
-SOcONbaf
------END PRIVATE KEY-----`
+const sampleKeyBase64 = "LS0tLS1CRUdJTiBQUklWQVRFIEtFWS0tLS0tCk1JR1RBZ0VBTUJNR0J5cUdTTTQ5QWdFR0NDcUdTTTQ5QXdFSEJIa3dkd0lCQVFRZ3NybVNBWklhZ09mQ1A4c0IKV2kyQ0JYRzFPbzd2MWJpc3BJWkN3SXI0UkRlZ0NnWUlLb1pJemowREFRZWhSQU5DQUFUWkh4VjJ3UUpMTUJxKwp5YSt5ZkdpM2cyWlV2NmhyZmUrajA4eXRla1BIalhTMHF6Sm9WRUx6S0hhNkVMOVlBb1pEWEJ0QjZoK2ZHaFhlClNPY09OYmFmCi0tLS0tRU5EIFBSSVZBVEUgS0VZLS0tLS0K";
 
 /**
  * Wait for a condition to become true until the timeout
@@ -75,11 +68,9 @@ describe("NotificationService", () => {
       ...process.env,
       APNS_KEY_ID: "1",
       APNS_TEAM_ID: "1",
-      APNS_KEY_PATH: "./dummy-path.p8",
-      APNS_BUNDLE_ID: "dev.bchen.ProjectInter"
+      APNS_BUNDLE_ID: "dev.bchen.ProjectInter",
+      APNS_PRIVATE_KEY: sampleKeyBase64,
     };
-
-    (fs.readFileSync as jest.Mock).mockReturnValue(sampleKey);
   });
 
   beforeEach(() => {
@@ -198,8 +189,8 @@ describe("NotificationService", () => {
   });
 
   describe('getAPNsFullUrlToUse', () => {
-    it('should return the production URL when NODE_ENV is set to "production"', () => {
-      process.env.NODE_ENV = 'production';
+    it('should return the production URL when APNS_IS_PRODUCTION is set to "1"', () => {
+      process.env.APNS_IS_PRODUCTION = "1";
       const deviceId = 'testDeviceId';
       const result = NotificationService.getAPNsFullUrlToUse(deviceId);
 
@@ -209,8 +200,8 @@ describe("NotificationService", () => {
       expect(path).toBe(`/3/device/${deviceId}`);
     });
 
-    it('should return the sandbox URL when NODE_ENV is not set to "production"', () => {
-      process.env.NODE_ENV = 'development';
+    it('should return the sandbox URL when APNS_IS_PRODUCTION is set to something other than 1', () => {
+      process.env.APNS_IS_PRODUCTION = "0";
       const deviceId = 'testDeviceId';
       const result = NotificationService.getAPNsFullUrlToUse(deviceId);