What language is Meta?

Meta (formerly Facebook) uses a variety of programming languages across its platforms, products, and services. The company has a diverse tech stack tailored to its massive scale and the specific needs of each service. Here are the main programming languages used at Meta:

1. Hack (PHP Dialect)

• Core Language: Meta originally started with PHP but developed Hack, a dialect of PHP, to address performance and scalability needs. Hack adds static typing and other features to improve code safety and performance.
• Use: Hack is used for much of Meta’s backend services, including the core Facebook application.
• Source: Hack: Programming Language

2. C++

• High-Performance Applications: C++ is used extensively at Meta for performance-critical backend services. It powers key systems such as the news feed, messaging, and real-time data processing.
• Source: Meta Engineering

3. Python

• Data Science and AI: Python is widely used for data analysis, machine learning, and automation. Meta developed PyTorch, a popular open-source machine learning framework in Python, which is extensively used both internally and in the AI research community.
• Source: PyTorch by Meta

4. Java

• Backend Services: Meta uses Java for building large-scale, distributed systems and backend services. It is particularly effective for services that require robust and scalable infrastructure.
• Source: Glassdoor Meta Engineering Reviews

5. JavaScript (React)

• Front-End Development: Meta developed React, a JavaScript library for building user interfaces. React is used extensively for the front-end of Meta’s platforms like Facebook, Instagram, and Messenger, enabling dynamic and responsive user interfaces.
• Source: React.js

6. Erlang

• Real-Time Messaging: Erlang is used for the backend infrastructure of Facebook Messenger due to its ability to handle large numbers of concurrent users efficiently.
• Source: Erlang Solutions

Conclusion:

Meta’s tech stack includes a mix of Hack (PHP) for core services, C++ for high-performance applications, Python for data and AI, Java for backend systems, JavaScript/React for front-end development, and Erlang for real-time messaging services. These languages allow Meta to scale and optimize its various platforms.

Sources:

• Meta Engineering Blog
• PyTorch
• React