Hey there 👋🐱 it's Peer, cofounder of Cal.com. today we are launching Cal.com 4.0 which is our largest release ever. Cal.com is going from a single product to a multi-product with the launch of Cal.com Platform, a headless scheduling API powered by Cal Atoms, a set of plug & play react components. ⚛️ story time 👇 when my YC company shutdown during covid i needed a job. And because i suck at interviews i did what i can do best: i started building. i saw a lot of other founders shutting down their business too, so i built a marketplace to hire ex-yc founders as contractors. you might be surprised, but we used calendly to facilitate the meeting and asked for their link during the onboarding. and to be frank, it sucked. its simply not what its built for. i couldnt manage users, people didnt had an account or typos in their links, they forgot to upgrade and most importantly: i could not customise the experience. it was fully branded, felt foreign and would not work at scale with so many issues. i needed something i could be in charge of. so i googled "calendly open source" and found 0 results. just a couple hackernews and reddit posts asking for the same damn thing. ~~two days later~~ (*imagine the french spongebob narrator voice*) i started hacking on a landing page and together with @baileypumfleet, calendso was born. we launched and, well, the rest you've probably seen here on product hunt. anyway, we took a bit of a detour from building the "developer focussed headless scheduling infrastructure" and started out building a consumer facing scheduling tool instead after buying the cal.com domain. why? well – we wanted to build something that would delight people first. the most pixel-perfect, fast, secure (SOC2, ISO27001, HIPAA), safe and accessible (open source) product for everyone. if you look into the market of developer tools, a lot of these "scheduling apis" have never been touched by a consumer. it's a group of developers thinking about "hmmm what do i think other developers need" and not "what is the best for the actual host and guest" you get scheduling apis that are outdated or just "a part of a broader offering of APIs" like Nylas, that dont get the love that they deserve. scheduling is hard. timezones suck, calendar apis are older than your grand dad (seriously) but after facilitating multiple millions of bookings with our consumer facing product we are now going back to our roots: Scheduling Infrastructure for absolutely everyone. we are dog-fooding our own apis, using our own components, so you can be sure what you are using for your next big idea has been battle tested by millions of people and designed by a team that really really cares about calendar scheduling. sometimes all you have to do is go full circle and start at the beginning. today we are launching cal.com 4.0 but we are just getting started! Peer p.s. huge shoutout to everyone who has been supporting us. it is truly inspiring to be working with such an awesome community and go from a small side project on github to an organization that eventually connects 1 billion people. 🙏

Wow! Even though I don't entirely understand everything, it seems pretty amazing, regardless... so I can only imagine what visitors think who actually do understand it.

Congratulations on the launch of Cal.com Platform! @peer_rich This platform offers the fastest and easiest way to integrate scheduling into your app. Free yourself from the hassles of timezones, calendar and conferencing APIs, and scheduling logic by leveraging Cal.com's robust scheduling technology for your next product. How customizable is the scheduling experience with Cal.com Platform? Can developers tailor it to fit their specific app design and requirements?

Also a former and longtime Calendly users here. Only been using Cal for a few months but immediately as a builder and engineer I saw the value right away. Really excited to see atoms ship today and look forward to integrating into my product. Congrats on the launch team.

Cal Atoms is the most exciting thing happening to scheduling infrastructure since Cal.com. There are so many possibilities like deeper integration into third party applications (e.g. branded Cal.com booking component inside a Papermark deck). Congrats on the launch! Congrats to the entire team!

Congrats cal.com team, another great milestone!

Very excited for this launch!

Hey folks. This looks killer. Great job putting it together. Do you have plans to create an explainer video that shows me in 3 minutes why I should use it?

Congrats on the release team. Can't wait to use it to build some automagical scheduling infra for my own product. Let's go 🔥

You guys have gone deep! Constantly impressed by the speed at which Cal.com is improving. Well done @peer_rich, @baileypumfleet and crew! P.S., Supabase sucks! 😉

Congrats on the launch guys, cal.com is my goto booking platform

Congrats team

Love it. It just works, and is somehow free???

I don’t see price anywhere! I’m excited about this, but weary… I am a marketplace for services, so it’s a core functionality… is it payed per user? That wouldn’t be an option…

Calendar scheduling is so surprisingly hard. Doctolib is $5bn+ company and you still can't do a simple query like "dermatologists that have a free slot on Thursday". Please go save them 🙇‍♂️

this vs just another relaunch of postgress 🤷

Love it! Clean docs and awesome old windows theme. Congrats to the team 🔥

Love this @peer_rich

Cal.com has been the best alternative for meeting appointment. V4 seems even nicer. This product remains one of the best open-source.

Ship, Ship, Ship — Ya love to see it. The Cerebro devs have been enjoying the building experience so far — I just came out of a product meeting about it.