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Home
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21st
21st
Ai programming tools
Y Combinator Logo
Winter 2026
Active
developer-tools
b2b
design-tools
San Francisco
Company
Jobs
0
https://21st.dev
Ai programming tools
Active Founders
Serafim Korablev
CEO / co-founder
co-founder of 21st. prev. build gaspump.tg (acq.), via exchange ($1.5b GTV)
Serafim Korablev
CEO / co-founder
co-founder of 21st. prev. build gaspump.tg (acq.), via exchange ($1.5b GTV)
Sergey Bunas
Founder
co-founder @ 21st.dev; ex deel
Sergey Bunas
Founder
co-founder @ 21st.dev; ex deel
YC Photos
21st
Founded:
2024
Batch:
Winter 2026
Team Size:
3
Status:
Active
Location:
San Francisco
Primary Partner:
Ankit Gupta
