What code is Amazon written in?

Amazon's technology stack consists of a variety of programming languages, each chosen for specific use cases depending on the system, service, or department. Here's an overview of the main programming languages used at Amazon:

1. Java

Java is one of the most commonly used languages at Amazon, especially for backend development and large-scale distributed systems. It is heavily used in Amazon's core infrastructure for building scalable and reliable services.

• Used For: Backend services, microservices, Amazon Web Services (AWS), and large-scale distributed systems like e-commerce.

2. C++

C++ is used where high performance and efficiency are required, particularly in Amazon's AWS infrastructure and other services that require low-latency operations.

• Used For: Performance-critical systems, AWS infrastructure, and services requiring low-latency and optimized memory management.

3. Python

Python is popular at Amazon, particularly in areas like automation, machine learning, and data processing. Python is also commonly used with AWS Lambda and for developing data-driven applications.

• Used For: Automation, data science, machine learning (especially with AWS SageMaker), and AWS scripting via the Boto3 SDK.

4. JavaScript/TypeScript (Node.js)

JavaScript and TypeScript are commonly used for frontend development, and Node.js is used in server-side applications, especially for AWS Lambda and other cloud-native applications. They are widely employed for building dynamic web applications and APIs.

• Used For: Frontend web development, server-side applications with Node.js, and building serverless architectures on AWS Lambda.

5. Ruby

Amazon has used Ruby for certain internal applications and tools. While not as widely used as other languages, Ruby on Rails has been employed in some Amazon projects, particularly in earlier stages of development or for rapid prototyping.

• Used For: Internal tools, some web applications, and rapid prototyping.

6. Go (Golang)

Go is increasingly popular at Amazon, especially for building microservices and cloud-native applications due to its simplicity, performance, and ability to handle concurrent operations efficiently.

• Used For: Microservices, cloud-native applications, and high-concurrency systems.

7. Perl

Historically, Perl was used in various parts of Amazon’s infrastructure, particularly in the earlier days. Although it is less commonly used now, it may still exist in legacy systems.

• Used For: Some legacy applications and internal tools.

Summary of Programming Languages Used at Amazon:

1. Java: Most common for backend services and large-scale systems.
2. C++: Used in performance-critical systems and AWS infrastructure.
3. Python: Popular for automation, machine learning, and data science.
4. JavaScript/TypeScript: Used for frontend and server-side applications (Node.js).
5. Ruby: Used in some internal tools and web applications.
6. Go: Increasingly used for microservices and cloud-native applications.
7. Perl: Used in legacy systems, though less common now.

Key Insights:

• Java and C++ dominate the backend systems and infrastructure at Amazon.
• Python is heavily used in machine learning, automation, and AWS scripting.
• JavaScript/TypeScript and Node.js are key for web development and serverless applications on AWS.
• Go is growing in popularity for building scalable, cloud-native microservices.

If you’re preparing for a technical role at Amazon, it’s crucial to be proficient in these languages, particularly Java, Python, or C++. For coding interviews, you can explore resources like Grokking the Coding Interview to sharpen your skills in the coding patterns Amazon often tests. Additionally, for system design roles, Grokking the System Design Interview will help you understand how Amazon builds scalable systems.