We have been publishing the top trending open-source startups every quarter since Q2 2020, and more than 30,000 developers, founders, and investors have visited the ROSS index to date.
Today’s update is truly a special one — after all these years, we are thrilled to open source the full index data in our GitHub repo, where one can monitor all future updates as well — just give it a star :)
As always, here’s our fresh top 10 for Q3 2025:
OpenCut (opencut-app/opencut, 32.0K stars, 32.0x growth) is a cross-platform video editor (alternative to CapCut). Founded in 2025.
🇺🇸 SST (sst/opencode, 22.1K stars, 22.1x growth) has built a full-stack deployment framework, and now is developing OpenCode, a terminal-based AI coding agent. Founded in 2017 in San Francisco. Raised $1.6M from Y Combinator, SV Angel, Greylock, etc.
🇺🇸 Upstash (upstash/context7, 20.9K stars, 20.9x growth) has built a serverless data platform, and now is developing Context7, an MCP server with up-to-date docs engine for LLMs. Founded in 2021 in San Jose, CA. Raised $11.9M from a16z, ScaleX, Mango Capital, Bek Ventures, etc.
🇺🇸 Hamster (eyaltoledano/claude-task-master, 17.4K stars, 17.4x growth) builds TaskMaster AI that transforms specs into AI-compatible tasks that integrate directly into dev tools. Founded in 2025 in San Francisco.
🇺🇸 Winfunc (winfunc/opcode, 16.6K stars, 16.6x growth) builds Asterisk, a codebase vulnerability automation system, and Opcode, a cross-platform client for Claude Code. Founded in 2024 in San Francisco. Raised an undisclosed amount from Y Combinator, Orange Collective, etc.
🇺🇸 Dyad (dyad-sh/dyad, 14.1K stars, 14.0x growth) is an AI builder for full-stack apps (alternative to Lovable). Founded in 2025 in San Jose, CA.
🇰🇷 Nari Labs (nari-labs/dia, 17.5K stars, 12.0x growth) develops advanced TTS models capable of generating ultra-realistic, expressive speech from text. Founded in 2025 in Seoul. Raised an undisclosed amount from Y Combinator.
🇺🇸 Astral (astral-sh/ty, 11.2K stars, 11.2x growth) builds high-performance Python tools, including ty, an extremely fast type checker. Founded in 2022 in New York. Raised $4M from Accel, Base Case Capital, Caffeinated, etc.
🇨🇦 Resemble AI (resemble-ai/chatterbox, 10.4K stars, 10.4x growth) produces ultra-realistic AI voices and detects deepfake audio in real time. Founded in 2018 in Toronto. Raised $12.2M from Craft Ventures, Firstminute, Javelin VC, etc.
🇺🇸 Kilo Code (Kilo-Org/kilocode, 9.3K stars, 9.1x growth) is an AI coding assistant. Founded in 2025 in San Francisco.
Get more data about other startups from the last quarter at ROSS Index Q3 2025.
It’s a pleasure to share that we participated in the $13M seed round of Mastra, a fast-growing AI agent framework for JavaScript/TypeScript developers. It was founded by a solid trio of open-source veterans — Sam, Shane, and Abhi — who previously built one of the most popular JS frontend frameworks, Gatsby.js.
Here you can find more context on why we have been so excited about this particular company, given the dynamic and quite competitive landscape of AI agent frameworks.
The index evolves with the support of its community, and in Q1 2024, we slightly tweaked our methodology. Now the startup list is based on maximum GitHub star growth within any 90-day period that ended in the target quarter. In a nutshell, our approach remains simple:
Monitor all GitHub repos with 1,000+ stars
Calculate the growth of stars during the target "sliding window" period
Select repos that are only associated with early-stage startups
Highlight the top 20 trending open-source startups by their GitHub star growth
There's no magic open metric representing the quality of tech companies. Our star growth-based approach highlights noteworthy early-stage startups leveraging open source that have been on developers' minds in the last quarter.
Since its launch in Q2 2020, all quarterly indexes are published on our website. You can easily contact us with your ideas on how to improve the index. Also, if you’re a lucky participant in the ROSS index’s top 20, feel free to let others know about this by adding a special badge on your GitHub repo or to your website.
Besides the ROSS index, we maintain our own open source repo: awesome list of open-source alternatives to established SaaS products. It already has 17,000+ stars and 100+ contributors. Join them or just give it a star 😊
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