C
S21Developer Tools2021✓ VERIFIED
Cal.com
Open-source scheduling infrastructure — the Calendly alternative developers actually want to self-host. 25,000+ GitHub stars and growing.
/ STORY
Rejected by YC. Peer Richelsen and Bailey Pumfleet open-sourced Cal.com instead.
The GitHub repo went viral. The community built integrations YC-backed competitors couldn't ship fast enough. Cal.com raised a $25M Series A and became the default scheduling infrastructure for teams who care about ownership.
/ DETAILS
Founder
Peer Richelsen
YC Batch Applied
S21
Rejected
2021
Category
Developer Tools
Bootstrapped
No
Verified
Yes
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