Discover the Fastest‑Growing JavaScript/TypeScript Repos of 2023

GitHub now hosts over 100 million repositories; to help developers discover the most exciting projects, the ROSS Index ranks the fastest‑growing open‑source startups.

The following five JavaScript/TypeScript repositories grew at least 400% last year and have attracted significant attention.

1. LangChain – Build Powerful AI Chatbots

LangChain is a comprehensive library and framework for building applications on large language models. It enables ChatGPT to access Wikipedia, weather data, Gmail, and more, providing all components needed to create sophisticated AI‑driven workflows.

For a practical example, see the open‑source CoverLetterGPT repository, which turns job descriptions and résumé PDFs into customized cover letters.

2. Wasp – The Fastest Way to Build Full‑Stack Web Apps with React and Node.js

Wasp simplifies full‑stack development by letting developers declare functionality in a configuration file, automatically handling boilerplate such as authentication, email verification, UI components, async tasks, and React Query data fetching.

Wasp‑built open‑source SaaS starter Open SaaS and the AI app generator MAGE showcase its capabilities.

3. Resend – Rethink How You Send Emails

Resend provides a flexible email API and dashboard for managing transactional and marketing emails, including tracking opens and handling spam. It powers the popular React Email repository (12k+ stars), making styled email creation easy.

4. Nebuly – User‑Experience Insights for AI Chatbots

Nebuly is an open‑source tool that lets developers and teams analyze how users interact with AI chatbots, offering metrics such as most asked questions, conversation topics, A/B testing, and content suitability.

5. Formbricks – Easy User Feedback Collection

Formbricks positions itself as an open‑source alternative to Typeform, allowing developers to embed customizable forms, collect survey data, and integrate with tools like Notion, Zapier, or Google Sheets.

These fast‑growing repositories illustrate the vibrant open‑source startup ecosystem and provide developers with powerful tools to accelerate their projects.