The Advanced Notification Systems of LinkedIn, Quora, and Airbnb: What notification components are being used?
Tags: devops, opensource, openai, linux
Published: 2023-10-13 05:08:19

For experienced CTOs and seasoned developers, the design and architecture of a notification system go beyond mere user engagement; it's a complex ecosystem that demands meticulous attention and robust infrastructure. In this in-depth exploration, we'll dissect the technical intricacies of notification systems employed by tech giants like LinkedIn, Airbnb, and Quora. We'll focus on the implementation of cutting-edge **notification system design** and the technologies powering these companies' **notification infrastructures**.


![Image description](https://dev-to-uploads.s3.amazonaws.com/uploads/articles/sxyzaaz57id38g2hwsew.png)



## Technical Foundations

LinkedIn, Airbnb, and Quora have each developed advanced **notification systems** that rely on essential components to deliver a seamless user experience.

### Delivery Channels & Vendor Integrations


![Image description](https://dev-to-uploads.s3.amazonaws.com/uploads/articles/ekdanyzsjq5of61abqqb.png)



Central to the success of these platforms is their utilization of diverse **delivery channels** and comprehensive vendor integrations. These companies are tightly integrated with various vendors, including SendGrid, Twilio, and Firebase Cloud Messaging, to reach users across email, SMS, in-app notifications, push notifications, and more. This integration is achieved through complex APIs, stringent quality-of-service standards, rigorous testing, and robust fallback mechanisms, ensuring notifications reach users efficiently and reliably.

### Templating Engine

![Image description](https://dev-to-uploads.s3.amazonaws.com/uploads/articles/kwd27hqm1v8qcnsf32f3.png)

At the core of these notification systems lies a versatile **templating engine** that adapts and optimizes messages for different channels. For example, Quora's system tailors messages for email, in-app notifications, and push notifications, accommodating varying content and formatting requirements.

Amazon Web Services (AWS) Simple Email Service (SES) provides a reliable solution for email delivery. However, it comes with a notable limitation — it lacks a built-in templating feature for crafting dynamic and customized email content. This limitation poses a challenge when you need to create personalized email content that adapts to user preferences and maintains a consistent brand image across communication channels. For these only, you can use a [third-party notification infrastructure solution](https://www.suprsend.com/products/templates) that provides templating and couples them with your preferred email vendors.

### User Preferences

![Image description](https://dev-to-uploads.s3.amazonaws.com/uploads/articles/ctp21zznljm7dq5ds01g.png)

Airbnb empowers users to finely tailor their notification experiences through a robust **user preference management system**. Users have granular control over notification types, preferred communication channels, delivery frequencies, and timing. This high degree of personalization ensures users receive messages in a way that suits their individual preferences.

You can get a self-hosted preference management center from here: [Give Control to Your Users with Preference Management | SuprSend](https://www.suprsend.com/products/preferences) without ever needing to code it.

### Batching and Digests

To prevent notification fatigue, companies like Airbnb employ strategies such as **batching and digesting**. These companies bundle related notifications into a single message and send summarized digests at preferred times, optimizing user interaction.

### Multi-Tenancy for Customers

![Image description](https://dev-to-uploads.s3.amazonaws.com/uploads/articles/8brjlcpjy4n9s8cv0du2.png)


LinkedIn provides robust **multi-tenancy support** to cater to a diverse customer base. This entails data isolation, on-brand templates, customized routing, and user preferences for each tenant or customer. Airbnb takes a similar approach by allowing property owners to receive branded notifications, customize communication channels, and maintain their unique brand identities within a shared infrastructure.

### Notification Analytics

![Image description](https://dev-to-uploads.s3.amazonaws.com/uploads/articles/vk6vbh3z2yzy1v1kxi4s.png)


For product managers, insights into **notification analytics** are invaluable. Tracking delivery rates, open rates, and user engagement enables data-driven optimizations. These companies collect user actions through webhooks and conduct cross-channel analysis, ensuring notifications are effective and engaging.

## The Pillars of Reliability

To maintain the reliability of their notification systems, these companies have established non-functional components.

![Image description](https://dev-to-uploads.s3.amazonaws.com/uploads/articles/4ut9wu4r7ppafyy9le3v.png)


### Scalability & Load Balancing

A notification system must handle varying levels of traffic, often peaking unexpectedly. Designing for **scalability** ensures the system can handle increased loads without performance degradation. Load balancing across servers and regions is vital for maintaining consistent service availability.

### Fault Tolerance, Redundancy & Failure Retries

In a notification system, downtime is not an option. Engineers must architect the service with **fault tolerance** and **redundancy mechanisms** to mitigate the impact of server failures or network issues. This involves setting up state management, configuring fallback vendors, and implementing failure retry mechanisms.

### High Deliverability

To ensure **high deliverability**, these companies introduce multiple channels, choose reliable vendors, and manage inactive channels to make certain that notifications consistently reach their intended recipients.

### Low Latency

Users expect notifications to arrive promptly. Minimizing **latency** requires optimizing message delivery paths, reducing network round trips, and optimizing database queries. This ongoing effort maintains high performance as the system scales.

### Observability & Diagnosis

Setting up monitoring is crucial for identifying and resolving issues when failures occur. Implementing detailed logging, error tracking, and performance monitoring allows for swift issue diagnosis and resolution.

### Message Queue Prioritization

Not all notifications are of the same priority. For instance, authentication notifications are high priority because users expect to receive OTPs instantly to log in. **Message queue prioritization** helps manage different notification priorities effectively.

## Making the Strategic Choice

![Image description](https://dev-to-uploads.s3.amazonaws.com/uploads/articles/ozu4k2xy5yeowyy1myst.jpg)
For CTOs and experienced developers, the decision to build an in-house notification system or leverage existing solutions is strategic.

**When to Build:**

- **Complexity and Customization:** If your business requires intricate customization and unique communication channels, an in-house solution offers control and flexibility.
- **Notifications as a Core Product:** If notifications are central to your product, building an in-house system allows for tailored solutions.
- **Resource Availability:** If you have the technical expertise and resources, building an in-house notification system can be advantageous.

**When to Consider Alternatives:**

- **Resource Constraints:** Building and maintaining a notification system can be resource-intensive. Leveraging existing notification platforms or APIs can be more efficient.
- **Time to Market:** Developing a notification system from scratch can be time-consuming. If speed is essential, third-party services can accelerate your product's launch.
- **Complex Features:** Established platforms offer complex features off the shelf, reducing development time and effort.
- **Focus on Core Competencies:** Getting notifications right requires time and learning, diverting your focus from core competencies.

In conclusion, whether you choose to build an in-house solution or rely on third-party services, the ultimate goal remains the same: providing a seamless and meaningful user experience that fosters lasting connections. By assessing your company's unique needs, resources, and long-term objectives, you can make an informed decision that aligns with your technical aspirations. Try SuprSend!