Which backend does Netflix use?

Netflix’s backend is built using a combination of cutting-edge technologies, microservices architecture, and cloud infrastructure to support its massive global streaming platform. The backend is designed to handle the complex requirements of high availability, scalability, and low-latency content delivery to millions of users simultaneously.

Key Components of Netflix's Backend

1. Microservices Architecture

Netflix’s backend is based on a microservices architecture, where different services are independently developed, deployed, and scaled. This allows Netflix to handle different tasks, such as user authentication, content recommendations, and streaming, through separate services that can communicate with each other.

• Microservices Built with Java: Many of Netflix’s microservices are written in Java due to its scalability and performance, making it ideal for building the distributed services that power the platform.
• Spring Boot: Netflix uses Spring Boot, a popular Java framework, to simplify microservices development and deployment.

2. Cloud Infrastructure (AWS)

Netflix runs its backend on Amazon Web Services (AWS), leveraging the scalability and flexibility of cloud infrastructure to manage its vast global user base.

• AWS EC2: Netflix uses Amazon EC2 instances to run its backend services, ensuring high availability and scalability.
• AWS S3: Content is stored and served using Amazon S3, a scalable object storage service that allows Netflix to store and retrieve video files efficiently.
• Global CDN: Netflix uses its own content delivery network (CDN), Open Connect, which is integrated with AWS for distributing content efficiently around the globe.

3. API Gateway

Netflix’s API gateway is an important part of its microservices architecture. The API gateway manages traffic, routing requests from clients (like mobile apps, web browsers, smart TVs) to the appropriate backend microservices.

• Zuul: Netflix uses Zuul, an API gateway solution, to handle and route requests to various microservices. Zuul also provides features like load balancing and request filtering.

4. Databases and Storage

Netflix uses a mix of databases and storage solutions to handle different types of data, from user information to content metadata.

• Cassandra: Netflix uses Apache Cassandra, a highly scalable NoSQL database, to handle distributed, large-scale data storage across multiple regions. It’s used for storing user data, viewing history, and other non-relational data.
• MySQL: For relational data storage, Netflix uses MySQL, primarily to manage user information and transactions.
• DynamoDB: Netflix also uses Amazon DynamoDB, a fully managed NoSQL database, for low-latency data retrieval in specific use cases.

5. Real-Time Data Processing

To provide personalized content recommendations and analyze user behavior in real time, Netflix processes large amounts of data quickly.

• Apache Kafka: Netflix uses Apache Kafka for real-time data streaming and event processing. This allows them to capture user interactions, such as playbacks, ratings, and searches, in real time.
• Apache Spark: For large-scale data processing, Netflix uses Apache Spark to process and analyze massive datasets, helping power recommendation systems and performance optimizations.

6. Resilience and Reliability

Netflix prioritizes uptime and service availability, relying on tools and practices that ensure resilience in its distributed system.

• Chaos Engineering: Netflix uses Chaos Monkey, a tool that randomly shuts down services in production to test the resilience and fault tolerance of its infrastructure.
• Hystrix: Netflix developed Hystrix, a fault-tolerant library that helps prevent cascading failures by isolating failures in one part of the system and ensuring that the rest of the services remain functional.

7. Backend Languages and Technologies

Netflix’s backend uses a variety of languages and technologies depending on the service and task.

• Java: The primary language for Netflix’s backend services and microservices.
• Python: Used for data analytics, machine learning, and automation tasks.
• Node.js: Occasionally used for specific backend tasks requiring lightweight, high-performance scripting.
• Go (Golang): Used for certain high-performance tools like Chaos Monkey.

Conclusion

Netflix's backend is a sophisticated blend of microservices architecture built primarily in Java, running on Amazon Web Services (AWS) for scalability and reliability. It uses a combination of NoSQL databases like Cassandra and DynamoDB, real-time data processing tools like Apache Kafka and Spark, and resilience-focused tools like Chaos Monkey to ensure seamless, reliable service delivery to millions of users globally. This backend infrastructure enables Netflix to efficiently manage its complex, large-scale streaming platform while delivering high-quality content across the globe.