The Most Used Programming Languages in Big Finance Companies

When discussing the programming languages used in big finance companies, it's important to understand the context of each company. Some firms rely heavily on legacy systems, while others are at the forefront of modern software development. This article explores the predominant languages in this industry and the reasons behind their usage.

Defining 'Big Finance Company'

The term 'big finance company' can be ambiguous, leading to different interpretations. One meaning could refer to a major financial institution such as an investment bank, hedge fund, or a large securities firm. Another interpretation might specifically refer to 'High Frequency Trading' (HFT) firms where milliseconds can be worth millions.

High Frequency Trading (HFT) Firms

In HFT companies, the focus is on rapid execution of trades with minimum latency. For critical trading systems, C is predominantly used due to its efficiency and performance. Some performance-critical code paths may even include assembly language. The trade logic itself is often implemented in C, while the policy setting applications might use Java for its robustness and ease of maintenance. Python is also commonly used for its flexibility and powerful libraries in quantitative analysis.

Legacy Systems and Policy Setting

Besides HFT firms, large, older finance companies often operate with legacy systems written in older languages like COBOL and FORTRAN. For example, TRW finance software might still use COBOL for its strong database and transactional capabilities. However, for new systems and policy setting, Java is now the preferred choice due to its scalability, throughput, and rich ecosystem of libraries.

Common Languages in Finance Companies

Besides C and Java, other languages also play significant roles in the software engineering landscape of big finance companies:

JavaScript, CSS, and HTML

Web dashboards for financial systems are typically built using modern web technologies such as JavaScript, CSS, and HTML. These languages allow for the creation of interactive and dynamic user interfaces, which are crucial for real-time financial dashboards.

Python and C

Backends for web dashboards and other high-performance applications often use Python due to its simplicity and extensive libraries, or C for its speed and flexibility. Python is popular in data analysis, whereas C offers better performance for complex financial models.

Boutique Languages and Personal Preferences

Some companies adopt 'boutique' languages because they might have a team leader who has a strong preference for a particular language. These languages can include languages like R for statistical analysis or Scala for concurrent and functional programming. However, these languages are usually used for specific tasks and may not be as prevalent as the more mainstream ones like C and Java.

Conclusion

While both C and Java are widely used in finance companies, C is most prevalent for building critical trading systems due to its performance. Java, on the other hand, is used where high performance is not a primary driver. COBOL and FORTRAN are still used in legacy systems, while JavaScript, CSS, and HTML are essential for web interfaces. The choice of language often depends on the specific requirements of the project and the preferences of the development team.