Top accelerator startups

14,448 startups · 29 programs

Reflex

Active · Build the software you wish existed.

12signal of 100 · rising 4
  • team of 15Team size · YC's directory+6.2
  • went through YCProgram · this site+4
  • hiringHiring · Titles (titles.fru.dev), YC+2

A sum of public facts, not a judgement and not investment advice.

Competitors

Adjacent

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About Reflex

For decades, businesses have adapted to software that wasn’t built for them. Teams pay for features they don’t need, go without the ones they do, and fill the gaps with spreadsheets, emails, and manual work. AI flips the equation. Now, software can be built around your business. Reflex brings AI and engineering expertise to your business without requiring you to become a software company. We work alongside your team to identify where better software can make the biggest difference, build on or replace your existing systems, and help you put it to work. Our platform gives every app a shared foundation, making your software easier to connect, maintain, and improve. As your business evolves, your software can evolve with it. That foundation is Reflex, our open-source framework for building full-stack web apps entirely in Python. With 1M+ apps built, approximately 29,000 GitHub stars, and usage by 30% of the Fortune 500, Reflex gives developers a shared foundation for building and extending applications, with source code they can inspect, customize, and run themselves.

YC batch
W23 · Winter 2023
Status, per YC
Active
Category
AI, Developer tools
Team size
15
Location
San Francisco, CA, USA
Checked
6h ago

YC tags: Developer Tools, Open Source, Web Development, Infrastructure, AI

Changes seen

Team sizeOct 29, 2026

Team went from 10 to 15 people.

One-linerOct 29, 2026

Rewrote its one-liner; it read "The operating system for building mission-critical enterprise apps."

TagsOct 19, 2026

Newly tagged AI; no longer tagged Artificial Intelligence.

Reflex in W23: 274 companies, 69% AI

Reflex: questions

Which YC batch was Reflex in?

Reflex was in Y Combinator's Winter 2023 batch (W23).

Is Reflex still active?

Y Combinator lists Reflex as active.

Where is Reflex based?

Reflex lists San Francisco, CA, USA as its location on YC's directory.