TypeScript overtakes Python and JavaScript

By August 2025, TypeScript had become the most-used language on GitHub, surpassing both Python and JavaScript for the first time. Over the preceding year, TypeScript added more than one million contributors — the largest absolute growth of any language on the platform.

A chart showing the top 10 programming languages on GitHub from 2023 to 2025. TypeScript rises to #1 in 2025, overtaking Python and JavaScript, which move to #2 and #3 respectively. Other top languages include Java, C#, PHP, Shell, C++, HCL, and Go. The chart tracks ranking changes over time on a dark background with colored lines representing each language.

Python also grew substantially, adding roughly 850,000 contributors year over year (+48.78%). JavaScript trailed both, gaining about 427,000 contributors (+24.79%). The widening gap suggests a structural preference rather than a passing trend.

Strongly typed languages are increasingly the default for new development, especially as AI-assisted coding becomes routine. A large share of failures in AI-generated code trace back to type mismatches, broken contracts, or faulty assumptions between components. Type systems act as guardrails: they catch errors earlier, reduce review churn, and make AI-produced changes easier to validate before reaching production.

For teams adopting AI in daily workflows, the practical takeaways are straightforward:

  • TypeScript is becoming the default starting point for new projects, particularly in AI-heavy environments.
  • Introducing types into an existing JavaScript codebase may reduce friction more effectively than swapping AI models or tools.

Python anchors AI infrastructure

Contributor counts reveal who uses a language; repository data reveals what they build with it. Looking at AI-focused repositories, Python stands apart. As of August 2025, nearly half of all new AI projects on GitHub were built primarily in Python.

A chart listing the most commonly used programming languages in AI-tagged projects on GitHub in 2025. Python ranks first with 582,000 repositories (+50.7% year over year), followed by JavaScript with 88,000 (+24.8%), TypeScript with 86,000 (+77.9%), Shell with 9,000 (+324%), and C++ with 7,800 (+11%). The chart includes brief descriptions of each language’s role in AI development, displayed on a blue gradient background with green geometric ribbon graphics.

AI projects now command a disproportionate share of open source momentum. Six of the ten fastest-growing open source projects by contributors in 2025 focused directly on AI infrastructure or tooling.

A table listing the fastest-growing open source projects on GitHub in 2025 by contributors. The top ten are zen-browser/desktop, cline/cline, vllm-project/vllm, astral-sh/uv, microsoft/vscode, infiniflow/ragflow, sgl-project/sglang, continuedev/continue, comfyanonymous/ComfyUI, and home-assistant/core. Growth rates range from 2,301% to 6,836%, with most projects marked as AI-focused. Displayed on a blue gradient background with the GitHub Octoverse ribbon graphic.

Python's dominance in this space isn't new, but its role is shifting. The data points to a move from experimentation toward production-ready AI systems, with Python increasingly anchoring packaging, orchestration, and deployment rather than living only in notebooks. That trajectory is likely to continue well into 2026.

The implications for practitioners:

  • Python remains the backbone of applied AI work, from training and inference to orchestration.
  • Production-oriented Python skills — packaging, typing, CI, containerization — are becoming more valuable than exploratory scripting alone.

Speed and reproducibility win

Beyond AI, the fastest-growing open source projects reveal a shared emphasis on speed, control, and predictable outcomes. Tools that prioritize performance and minimalism are gaining traction quickly.

One clear example is astral-sh/uv, a package and project manager that dramatically accelerates Python package management. Its rapid growth reflects a growing intolerance for slow feedback loops and non-deterministic environments. When multiple projects of this kind surge simultaneously, it signals a broader trend — one that aligns closely with AI-assisted workflows where iteration speed and reproducibility directly impact developer productivity.

What developers are signaling with their choices:

  • Fast installs and deterministic builds matter as much as feature depth.
  • Tools that eliminate “works on my machine” scenarios are winning mindshare.

Where new contributors arrive

As the developer population expands, the entry points for first-time contributors become increasingly telling.

A chart showing the open source projects that attracted the most first-time contributors on GitHub in 2025. The top ten are microsoft/vscode, firstcontributions/first-contributions, home-assistant/core, slackblitz/bolt.new, flutter/flutter, zen-browser/desktop, is-a-dev/register, vllm-project/vllm, comfyanonymous/ComfyUI, and ollama/ollama. Displayed on a blue gradient background with green 3D ribbon graphics.

Projects like microsoft/vscode and firstcontributions/first-contributions continued to top the list over the past year, reflecting both the scale of widely used tools and the persistent demand for low-friction on-ramps into open source. (Contributions are defined here as any content-generating activity on GitHub.)

Yet basic project governance remains uneven across the ecosystem. README files are common, but contributor guides and codes of conduct are still relatively rare — even as first-time contributions keep climbing. Most projects on the fastest-growing list have thorough documentation on what the project does and how to contribute, suggesting that clear guidance is a significant driver of participation.

For maintainers looking to grow their communities:

  • Clear documentation lowers the barrier to contribution more than new features do.
  • Contributor guides and codes of conduct help convert curiosity into sustained participation.
  • Improving project hygiene is often the fastest path to a larger contributor base.

AI is no longer a separate category of development — it is shaping the languages teams select, the tools that gain traction, and the projects that attract contributors. TypeScript is becoming the default for reliability at scale, while Python holds its ground as AI systems move from prototypes into production. Across the ecosystem, developers are gravitating toward tools that minimize friction: faster feedback loops, reproducible environments, and clearer contribution paths.

The full 2025 Octoverse report contains additional data for those who want to dig deeper and draw their own conclusions.