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:
TAGS
Coding Interview
Facebook
CONTRIBUTOR
Arslan Ahmad
ex-FAANG engineering manager and author or Grokking series.
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