Cal.com is going closed source • Hacker News Board

Re: Cal.com is going closed source

#91

Post by evanelias » Wed, Apr 15, 2026, 6:54 PM UTC

toast0 wrote: post #26

Peer_Rich wrote: post #5

Earlier quoted context omitted.

hey cofounder here. since it takes my 16 year old neighbors son 15 mins and $100 claude code credits to hack your open source project

I don't think this really helps that much. Your neighbor could ask an LLM to decompile your binaries, and then run security analysis on the results. If the tool correctly says you've got security issues, trying to hide them won't work. You still have the security issues and someone is going to find them.

If I understand correctly, their primary product is SaaS, and their non-DIY self-host edition is an enterprise product. So your neighbor wouldn't have access to the binaries to begin with.

Re: Cal.com is going closed source

#92

Post by abound » Wed, Apr 15, 2026, 7:08 PM UTC

This certainly makes me feel better about the project I started a few months ago to replace my Cal.com instance with a smaller, simpler self-hosted tool

https://git.sr.ht/~bsprague/schedyou

Re: Cal.com is going closed source

#93

Post by no_wizard » Wed, Apr 15, 2026, 7:14 PM UTC

esafak wrote: post #40

gouthamve wrote: post #3

This is a weird knee-jerk reaction. I feel like this is more a business decision than a security decision. I feel like with AI, self-hosting software reliably is becoming easier so the incentives to pay for a hosted service of an OSS project are going down.

Their product is getting commoditized: https://workspace.google.com/resources/appointment-schedulin...

I always felt it was a matter of time before Google took notice.

It has always been odd to me they didn’t have this functionality years ago. It’s been requested for a long long time

Re: Cal.com is going closed source

#94

Post by righthand » Wed, Apr 15, 2026, 7:14 PM UTC

Good for them. I’m sure they saw the writing on the wall when Monday.com was cloned. This is the right move.

Re: Cal.com is going closed source

#95

Post by abound » Wed, Apr 15, 2026, 7:14 PM UTC

fontain wrote: post #88

Monumentally dumb given their codebase is already public and the type of security issues that exist in software are usually found in the oldest code. But also, and more importantly, cal.com launched coss.com last year, open source is (ostensibly) their DNA. How could they do a complete 180 on something so fundamental and think that wouldn’t worry customers, much more so than their codebase being public? I cannot even…

Oh wow the coss.com thing makes this so much worse. Making such an aggressive and public commitment to open source to then turn around and do something like this is a pretty rough look.

Re: Cal.com is going closed source

#96

Post by OsrsNeedsf2P » Wed, Apr 15, 2026, 7:28 PM UTC

DrammBA wrote: post #56

simonw wrote: post #11

Drew Breunig published a very relevant piece yesterday that came to the opposite conclusion: https://www.dbreunig.com/2026/04/14/cybersecurity-is-proof-o... Since security exploits can now be found by spending tokens, open source is MORE valuable because open source libraries can share that auditing budget while closed source software has to find all the exploits themselves in private. > If Mythos continues to find e…

I have a feeling the real reason is them trying to avoid someone using AI to copyright-wash their product, they're just using security as the excuse.

An app like Cal.com can be vibe coded in a few evenings with a Chrome MCP server pointed to their website to figure out all the nooks and crannys. The moat of Cal.com is not the code, it's the users who don't want to migrate.

The real answer is they are likely having a hard time converting people to paid plans

Re: Cal.com is going closed source

#97

Post by analogpixel » Wed, Apr 15, 2026, 7:32 PM UTC

TIL I learned about yet another calendar application I don't need. Someone should setup their openclaw to just write a new todo/calendar app each week; they'll be billionaires by the end of the year.

Re: Cal.com is going closed source

#98

Post by [deleted] » Wed, Apr 15, 2026, 7:39 PM UTC

[deleted]

Re: Cal.com is going closed source

#99

Post by lisperforlife » Wed, Apr 15, 2026, 7:39 PM UTC

DrammBA wrote: post #56

simonw wrote: post #11

Drew Breunig published a very relevant piece yesterday that came to the opposite conclusion: https://www.dbreunig.com/2026/04/14/cybersecurity-is-proof-o... Since security exploits can now be found by spending tokens, open source is MORE valuable because open source libraries can share that auditing budget while closed source software has to find all the exploits themselves in private. > If Mythos continues to find e…

I have a feeling the real reason is them trying to avoid someone using AI to copyright-wash their product, they're just using security as the excuse.

Exactly this! Classic open source bait and switch.

Re: Cal.com is going closed source

#100

Post by maxloh » Wed, Apr 15, 2026, 7:40 PM UTC

ButlerianJihad wrote: post #6

This seems kind of crazy. If LLMs are so stunningly good at finding vulnerabilities in code, then shouldn't the solution be to run an LLM against your code after you commit, and before you release it? Then you basically have pentesting harnesses all to yourself before going public. If an LLM can't find any flaws, then you are good to release that code. A few years ago, I invoked Linus's Law in a classroom, and I was…

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