Though Vuze was also one of the earliest clients and it's also open source for some reasons it never really became popular. Maybe because it's a Java client?
- 80-90% of the web's servers (something like nginx 35%, Apache 30%, cloudflare 20% who I believe run Linux for a large chunk of their infrastructure, litespeed 10%)
- stock market. I've read a number of articles discussing how NYSE, Tokyo, and NASDAQ run their trades and servers on Linux.
- internet infrastructure: From Linux to ssl to VPN sooooo much of internet's infrastructure is open source. From the servers to the protocols to the stacks. I don't have hard numbers but I'd be comfortable guessing at least 3/4 of the net's infra is open source.
- Git
- Firefox
- Wikipedia
- Home Assistant
- OBS
- Linux
- VLC
- DaVinci Resolve is rising soooo fast for video editing, and for good reason. Once you move out of the consumer/hobbyist tier or beyond Premiere and more into pro-tier hardware Resolve is fucking incredible. It will be a couple of years before it displaces Avid's strangle hold on the film industry, but it's going to happen.
- Blender
encoders, while you may not notice it, a ton of the media we consume is coded with open source, from:
- AV1 of Netflix/Amazon/Youtube fame
- VP9
- x264
- x265
- Apple Lossless, etc...
- ffmpeg
- Android is built off AOSP.
- Wordpress
And obviously I'm missing thousands of used-in-production very "succesful" projects.
Cal.com is open-source Calendly, has raised $32M, and shares their stats publicly: https://cal.com/open
PostHog is open-source Mixpanel/Amplitude, has raised $39M, and appears to be widely recommended these days.
This database-free FOSS wiki engine [1] with a focus on simplicity is 19 years old, still gets updated, has useful plugins [2] for additional features, is a great choice for many uses, has adopters that use and love it, and has an estimated 50,000-250,000 installations [3].
As someone wrote, "DokuWiki is and will remain king for many simple reasons" [4].
[1] https://www.dokuwiki.org
[2] https://www.dokuwiki.org/plugins
[3] https://www.dokuwiki.org/faq:installcount
[4] https://old.reddit.com/r/sysadmin/comments/145l121/what_wiki_do_you_recommend/jnmd2t7/But I think the more interesting perspective is to reverse the question: where are proprietary software specifically successful?
Many years ago I'd noted that the concept of a shrinkwrap-based software company had very few successful exemplars. Microsoft and, perhaps Adobe, being the best-known cases. Through the mid-aughts, most other "software" firms had tremendous consulting arms: IBM, Oracle, Peoplesoft, SAP, Symantec, Informix, and the Big-N consulting companies notably.
Since the mid-aughts, SAAS and social media companies have arisen, though that's still a segment where a very small number of companies come to claim a monopoly position, largely due to adtech dynamics (on both ad sales aggregation and surveillance data).
Actual shrinkwrap software markets are increasingly marginal, fighting for table scraps, with the remaining large participants (Microsoft, Adobe) increasingly headed to subscription and/or ad-supported business models.
Firefox. Atom/VSCode (Sublime Text clones). Android (iOS clone).
Various databases (postgres, mongodb, etc).
Reddit (Digg alternative, since closed source) though I'm not sure releasing their source code had anything to do with their success.
HashiCorp in general sort of counts though it's harder to say "it was competing against X".
I think vBulletin still operates on this model, although they now offer it as a service too. phpBB is the oldest alternative to vBulletin, there are plenty.
Eventually all these CMSs from the 2000s were cloned and freed in some way or another. Our "SaaS" was cpanel which automagically installed these (they were THIS close to "serverless", if they only knew). By 2010, people barely knew what MovableType was.
cpanel is gone, shared hosting is gone, but that cloned freed CMS tech evolved and still powers a large chunk of the web.
Why doesn't it happen now? I don't know. Maybe it takes time, maybe that was a lucky decade, maybe it's happening in some place I'm not looking at.
I think Blogger was the main alternative back then, but there were probably several commercial ones with reasonable market share.
Vector based editing tool
Desktop publishing
Outline (https://www.getoutline.com) is successful on most metrics you'd judge a business and OSS project on.
I'm not sure if any of these ever pitched themselves explicitly that way on HN though. I think explicitly labeling as an "Open source alternative" brings a lot of baggage and expectations, and often says more about the maintainers philosophical POV than ability to create a sustainable business ;)
Though it is true that LibreOffice, ffmpeg, and Linux are successful and widely used, I was much more curious whether the small ShowHN ones got anywhere. And I barely found any.
All (recent) FOSS success stories come from the proprietary apps being so screwed up. (At least that's my impression)
This is not to disregard the meaningful thought and work that goes into the proprietary layers built on top of the open source codebases. But, we should all acknowledge that without those extremely high quality open source codebases, most SaaS wouldn't exist in the first place.
Of course there can be a USP and quality aspect, take basic resource metrics for example, you can pay someone to do that for you, or you can do it yourself, the difference in effort is marginal but the difference in cost can be extreme. But there are cases where that marginal difference in effort is what tips the choice towards paying someone else to do it. In my experience, if you cannot make such efforts, or don't have a plan to make such efforts in the future, you're either in the wrong business or are doomed to fail purely on PnL.
I use Insomnia every day.
Thus far the only cases where the MS Office users don't gradually slide into the gravity of an OnlyOffice service on private silicon is the heavy MS Excel (desktop) users who are of a very relevant (CFO, accounting) yet relatively small cohort.
It was originally released as freeware, but after it was widely adopted in the mid 1990s, its creator made it proprietary and created a company called SSH Communications Security to sell it. After a series of security vulnerabilities in that commercial software, OpenBSD developers got fed up and created OpenSSH, and basically everyone migrated to that within a year.
Javascript being an open standard meant there were no barriers to re-implementing them on alternative browsers. So when Internet Explorer started to lose its throne to Chrome and Firefox, Javascript survived while VBScript did not. When Apple decided to introduce webkit but not Flash to iOS, Javascript survived while Flash did not.
There's also uBlock Origin, but I don't know if it's the largest adblocker yet. It should be, though. I think it is a serious competitor, even in terms of market share, to many major for-profit adblockers.