JavaScript has 28 million users: What this reveals about the future of Global Tech teams

SlashData Team
2 hours ago
4 min read

The tools developers choose say a lot about the future of software and the businesses that support it. Programming languages are more than syntax; they shape hiring, tooling, revenue models, and even operational risk. That’s why SlashData’s latest Q1 2025 Developer Nation report offers essential insights not just for engineers, but for business function leaders, operations teams, and strategists across the global tech ecosystem.

Here’s why this matters for decision-makers;

JavaScript Still Reigns Supreme But Growth is Slowing

With 28 million active developers, JavaScript remains the world’s most-used programming language. It’s used across virtually every software domain, making it an indispensable skill in both front-end and full-stack roles.

That being said, JavaScript’s growth is slowing. While it still added 2.8 million new developers in the past year, this is modest compared to expansion in previous periods. This may indicate a maturing market which is something teams should watch when forecasting tool adoption or developer availability.

Why it matters:

JavaScript is essential but competitive. Teams hiring for JS-heavy roles should consider differentiating to attract top talent. Culture, projects, or compensation are only a few examples.

Java Surges Ahead of Python

For the first time in recent years, Java (23.2M developers) has surpassed Python (22.9M) to become the second-largest language community. Java’s strength lies in its consistent growth across multiple development domains from desktop to game development.

This distributed growth suggests long-term resilience. Unlike trends driven by a single technology (like Python and AI/ML), Java’s adoption is diversified and stable.

Why it matters:

Enterprise-ready, reliable, and multi-domain, Java is a safe bet for scaling teams especially those managing legacy systems or building for high-availability environments.

Rust and Swift See Big Growth With AI’s Help

Rust added 1.1M developers this year, now reaching 5.1M globally. It’s growing steadily, supported by its memory safety, performance, and appeal in secure system design.

Swift also saw a surprise resurgence, jumping from 4.6M to 5.6M developers. This growth was likely fueled by the rise of AI coding assistants. 42% of Swift developers use tools like GitHub Copilot, compared to 32% of developers overall.

Ruby followed a similar pattern, with a 1.6M increase year-over-year. AI tooling appears to be lowering the learning curve for languages previously considered niche or difficult.

Why it matters:

When evaluating tools, onboarding time, or training needs, language-community trends shaped by AI support should be part of your planning.

Midsize Languages with Specialised Appeal

Languages like Kotlin (6.3M), C# (11.1M), and Go (5.0M) show strong presence in specific ecosystems such as Android development, enterprise platforms, and cloud-native tooling, respectively.

These languages may not lead in total users but are critical in vertical markets. Teams focused on mobile, backend scalability, or DevOps should keep these ecosystems in scope.

Why it matters:

Specialisation matters. A smaller language community can still represent a critical competency for strategic hires or partnerships.

C and Rust Are Favoured by High Earners

SlashData’s income analysis shows that high-earning developers are more likely to use C and Rust, languages associated with performance, reliability, and foundational system development.

This suggests a connection between deep technical expertise and compensation, which is especially true in roles where performance and security matter.

Why it matters:

Upskilling in performance-focused languages can yield strong ROI for tech talent and the companies that employ them. It’s also a signal of where critical infrastructure investments may be headed.

PHP and JavaScript Dominate the Lower-Income Brackets

Interestingly, PHP and JavaScript see higher usage among lower-income developers. For PHP, the explanation may lie in its popularity among freelancers and micro-businesses. 35% of companies with fewer than five employees use PHP, compared to just 19% of enterprises.

JavaScript’s ubiquity makes it widely used, but also highly competitive, which can suppress wage growth in some markets.

Why it matters:

Language choice can signal market segment, pricing pressure, or training needs. Business teams working on pricing models or developer outreach should factor this in.

New Developers Experiment & Then Specialize

Developers with less than five years’ experience use more programming languages (avg. 4.2) than those with 16+ years (avg. 3.4). This reflects a natural progression: early-career developers explore, while experienced professionals focus on depth.

This insight is useful for workforce planning, especially for training programs or internal mobility strategies.

Why it matters:

New hires may require time to settle into a language ecosystem. Plan for ramp-up time and give room for experimentation.

The Big Picture: 47 Million Developers, 17 Major Languages

As of Q1 2025, there are 47 million active software developers globally. JavaScript, Java, and Python account for the lion’s share, followed by C++, PHP, C#, and a cluster of rising stars like Rust, Swift, Kotlin, and Go.

For business and operations teams, these numbers aren't just academic. They help answer critical questions:

Are we choosing languages our current and future teams can support?

Do we understand where to find (and how to retain) top talent?

How do language ecosystems affect vendor choice, tooling integration, and roadmap planning?

Conclusion

Programming language trends are a window into developer behavior, talent markets, and operational strategy. For product leads, hiring managers, operations teams, and executives, these insights are key to making smarter decisions in tech.

SlashData’s research doesn’t just explain what developers are doing, it helps global tech companies understand what’s possible, next.

To dive deeper into the data or access more developer ecosystem insights, visit: https://www.slashdata.co/free-resources

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