Introduction to notification infrastructure

In most systems, notifications start simple. You send an email when a user signs up for your product, when they complete a task, or when their trial is about to expire.

Most v1s of this system can just be an API call to SendGrid, Resend, or another transactional email service.

But as you introduce new features, like accepting payments, users may expect a more timely channel, like SMS, if their payment fails. Now you need to call the Twilio API.

If you’re a B2B SaaS product, your users may spend their lives in Slack or Microsoft Teams. Now you need another integration and yet another API call to a different provider.

Unfortunately, scaling notifications across each channel isn’t as simple as adding an API call in most cases. Not only does the code to send cross-channel notifications become more complicated, but your platform layer will need to evolve as well. At a certain point, you’ll need to think about different message formatting, message queues and failover strategies, idempotent sends, observability, and much more.

Notifications may start simple, but rarely stay that way. As Yegor Yakovishen, the Senior Engineering Manager at Gorgias, puts it:

Building reliable, consistent, scalable notifications requires a dedicated, cross-channel notification platform.

In this chapter, we’ll break down the typical path that leads companies to needing a more comprehensive solution for notifications and explain the benefits that notification infrastructure provides.

What are notifications?

Notifications are messages your application sends to users when specific events occur, and notifications across channels share properties although their functions in your product may differ.

At their core, notifications serve three key purposes:

1. Information. Notifications can inform users that something has happened, like an order has shipped or a payment has been received.
2. Activation. Notifications can get users to take desired actions, like verifying an email address or completing their account setup.
3. Engagement. Notifications can encourage users to engage with your product, such as highlighting a new product feature or new content posted by a friend.

Typically, notifications fall into several different categories based on the trigger that generates them:

• Transactional notifications. Triggered by user actions that require immediate confirmation or information, like order confirmations, password resets, two-factor authentication codes.
• Behavioral notifications. Sent based on user activity patterns to drive engagement or completion, like abandoned cart reminders, milestone achievements, or inactivity alerts.
• System notifications. Critical updates about platform operations and account security, like maintenance windows, security alerts, or API rate limit warnings.
• Social notifications. Updates about interactions with other users on your platform, like new followers, comments, mentions.

At a technical level, most notifications shares the same properties:

• Trigger: The event that initiates the notification.
• Payload: The actual message content, including title, body, and any associated data.
• Channel: The delivery mechanism (email, SMS, push, in-app, chat).
• Recipient: The target user and their delivery preferences.
• Metadata: Tracking information, timestamps, and delivery status.

The channel determines how it reaches the recipient, and modern products rarely rely on just one.

This means the recipient isn't just an email address anymore. It's a complex profile of channel preferences, time zones, and engagement history. Successful products need to navigate this complexity while delivering value without overwhelming a user.

What is notification infrastructure?

Notification infrastructure is an orchestration layer that handles the complexity of sending messages across multiple channels, like email, SMS, push, in-app, and chat, from a single API. It sits between your application and the dozens of downstream providers that actually deliver messages, such as Twilio, SendGrid, APNs, and many more.

At its core, notification infrastructure solves four problems:

1. Provider abstraction. Instead of integrating Twilio for SMS, SendGrid for email, and Firebase for push notifications, each with different APIs, authentication methods, and failure modes, you integrate with the platform once. It maintains connections to all providers and translates your messages into their required template formats.
2. Cross-channel orchestration. Modern users expect thoughtful notification experiences across different channels, such as a payment failure notifying via email first, push notification after 5 minutes if unread, and then SMS as a last resort. A notification infrastructure platform is built to handle this level of orchestration.
3. Delivery optimization. Ensuring reliable, scalable delivery requires queuing for rate limits, retries for failures, fallbacks when primary channels fail, and routing logic based on user preferences, and many other advanced functionalities.
4. State management and analytics. It’s important to track delivery status, handle bounces, manage unsubscribes, respect user preferences, and maintain audit logs. Notification infrastructure platforms offer APIs for querying message status, webhooks for delivery events, and dashboards for monitoring.

The technical architecture typically includes:

• Message queues that buffer notifications and handle spikes
• Worker pools that process messages and handle provider-specific formatting
• State stores that track message status and user preferences
• Real-time systems for in-app notifications via WebSocket
• Template engines that merge data with message templates
• Analytics pipelines that aggregate metrics across channels

Without a notification infrastructure platform, teams have to build this infrastructure themselves, which includes managing provider relationships, handling failures, creating preference centers, and maintaining templates across various channels.

Just ask Yakovishen about the shortcomings of Gorgias’ in-house system prior to implementing Knock:

A notification platform like Knock abstracts this complexity behind a simple API. Trigger a notification workflow with user data, and the platform handles the rest.

Key features of notification infrastructure

Building this infrastructure yourself means architecting message queues, implementing retry logic, managing provider connections, and handling thousands of edge cases. It's months of engineering work before you can send your first reliable notification, and years of ongoing maintenance as providers change APIs, new channels emerge, and the demands on your systems grow.

This is precisely why notification infrastructure platforms exist: to provide production-grade infrastructure that handles these complexities for you, allowing you to focus on your product.

Below, you’ll see what these platforms offer, and why they've become essential for modern applications.

Essential capabilities of a notification infrastructure platform

• Multi-channel workflows: Send notifications across email, SMS, push, in-app, and chat from a single API. Define fallback sequences—if the push fails, attempt to send an SMS, then an email. The platform handles channel-specific formatting, delivery requirements, and failure scenarios automatically.
• Template management: Dynamic templates are adaptable across channels, so you can write once and deliver everywhere. Personalize messages with variables and logic (if/then, loops), automate translation, and take advantage of version control with instant rollback. Visual editors enable non-technical users to update copy without code deployments.
• Delivery optimization: Providers should automate retries with exponential backoff, utilize provider failover when primary services are down, and support rate limiting to respect both provider limits and user preferences. Time zone awareness will prevent 3 AM notifications, and smart batching will help reduce notification fatigue by grouping similar notifications into digests.
• User preferences: Manage centralized preference centers with granular controls, so users can control their notification frequency and channels. API and UI components make it easy to seamlessly integrate with your app.
• Real-time observability + analytics: Get complete visibility into your notification engine, from your initial API request to message sent, making it easy to debug delivery failures and other issues. Track delivery rates, open rates, and engagement across all channels in one dashboard.
• Developer experience: Speed through implementation with SDKs for major languages, RESTful APIs with clear documentation, and sandbox environments for safe testing. The platform processes events from your existing systems and ensures idempotency to prevent duplicate sends.

Benefits of using a notification infrastructure platform

• Faster implementation. What takes months to build can be integrated in just days, and you can add new channels in hours, not sprints. That way you can test channel effectiveness without building the infrastructure.
• Reduced complexity. One API instead of learning Twilio, SendGrid, Firebase, and Slack APIs. Unified error handling and monitoring. No certificate management or provider authentication. Automatic API version updates.
• Cost optimization. Platforms negotiate volume discounts and pass savings through. Intelligent routing sends data through the cheapest and most reliable channel. Failed delivery detection stops wasting money on invalid addresses. Deduplication prevents expensive duplicate sends.
• Improved reliability. 99.95%+ uptime SLAs with multi-region deployments. Automatic failover between providers. Expert teams manage provider relationships. Battle-tested retry logic and queue management.
• Built-in compliance. GDPR consent management, CAN-SPAM compliance, SMS opt-out handling. Audit logs for regulatory requirements. Data residency options. Automatic unsubscribe handling across all channels.
• Scale without the overhead. Handle millions of messages without hiring an infrastructure team. Automatic scaling for traffic spikes. No capacity planning or queue management. Focus on your product, not notification infrastructure.

The question isn't whether you need these capabilities (you do). The question is whether to build them yourself, with months of engineering effort, or integrate a platform that provides them immediately.

As the CTO at Gorgias, Alex Plugaru thinks about this a lot:

Curious to hear about the results? Read how Gorgias improved customer service response times by 27% with Knock.