Mike Miller
December 13, 2024

Table of contents
We’re excited to confirm that Courier customers are unaffected by this update. Notifications sent via APNS with P8 keys or P12 certificates work seamlessly, and no changes are required.
Read more about what we tested
Apple is updating its Push Notification service (APNs) certificates to use the USERTrust RSA Certification Authority (SHA-2 Root). Key dates include:
To keep push notifications working, you must update your server’s Trust Store to include the new certificate authority. Both old and new certificates should remain trusted during the transition. Read Apple’s official announcement here.
We’ll update this post with details for `node-apn` and similar packages after January 20. Be sure to bookmark this post!
Courier has already implemented these changes, so you don’t need to worry. Notifications will flow seamlessly with no extra work on your part. Courier also lets you design and manage notification templates effortlessly. Explore Courier’s resources to get started:
If you are not using Courier, here's what you need to do:
If you’re updating manually, follow these steps:
Get the USERTrust RSA Certification Authority (SHA-2) certificate from Apple’s official site or a trusted source.
Unix/Linux Servers:
ca-certificates directory (e.g., /etc/ssl/certs/).Copied!
sudo cp /path/to/USERTrustRSA.crt /etc/ssl/certs/
Copied!
sudo c_rehash
Windows Servers:
If you’re using .p8 keys for APNs authentication, no changes are required for your app’s code. However, you still need to:
Skipping these updates may cause:
By preparing now, you’ll ensure your push notifications continue without interruption. If you need help, consult Apple’s documentation or contact your notification provider. Let’s make 2025 a seamless year for your app’s notifications!

Vibe Coding Notifications: How to Use Courier with Cursor or Claude Code
Courier's MCP server lets AI coding tools like Cursor and Claude Code interact directly with your notification infrastructure. Unlike Knock and Novu's MCP servers that focus on API operations, Courier's includes embedded installation guides for Node, Python, Flutter, React, and other platforms. When you prompt "add Courier to my app," your AI assistant pulls accurate setup instructions rather than relying on outdated training data. OneSignal's MCP is community-maintained, not official. Courier supports 50+ providers, native Slack/Teams integration, drop-in inbox and preference components, and a free tier of 10,000 notifications/month. Configure in Cursor with "url": "https://mcp.courier.com" and "headers": { "api_key": "YOUR_KEY" }.
By Kyle Seyler
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How Top Notification Platforms Handle Quiet Hours & Delivery Windows in 2026
No platform offers per-template delivery windows in 2026—it's either per-workflow (Customer.io, Knock), per-campaign (Braze), or global settings. This comparison shows exactly how six platforms handle quiet hours and send time controls based on their documentation and API specs. Braze leads on AI timing (23% open rate lift from Intelligent Timing across their customer base). Novu is the only platform letting subscribers set their own delivery windows. Customer.io and Knock require manual workflow configuration. OneSignal's strength is push-specific optimization across 300K+ apps. Courier combines per-node flexibility with API control. Includes feature matrix, timezone handling, and frequency capping differences.
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Notification Observability: How to Monitor Delivery, Engagement, and Provider Health
Notification observability is the practice of monitoring notification delivery, engagement, and provider health using the same tools and discipline you apply to the rest of your application infrastructure. It means tracking whether messages are delivered, opened, and acted on across email, SMS, push, and in-app channels, then surfacing that data in dashboards alongside your other application metrics. Key metrics include delivery rate by channel, bounce and failure rates, provider latency, open rate trends, and click-through rates by template. Teams can build notification observability through DIY webhook handlers that pipe provider events to Datadog or Prometheus, log aggregation from application send logs, or notification platforms with built-in observability integrations. This matters most for multi-channel systems, business-critical notifications like password resets and payment confirmations, and teams using multiple providers with fallback routing.
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