https://www.overleaf.com/help/17-is-overleaf-open-source#.WB...
An open-source business that doesn't survive (cough ReplicaDB cough) isn't necessarily better than a closed-but-extensible one that does. LaTeX itself is, and anything you're working on within Overleaf can be exported as text at any time, so I don't worry so much about lock-in.
The underlying toolchain (LaTeX and packages) is fully OSS, and isn't going anywhere; I have supported the LyX project in the past, and indeed that's how I laid out my dissertation, but in the end I find Overleaf more usable.
I still wish they'd support Markdown, though. Sometimes I just want to run off a quick, properly typeset series of equations and lists/tables without all the boilerplate. I suppose you could make the argument "well, if it was OSS, you could just patch it yourself!", and you wouldn't be wrong. But we use the autosubmit feature a lot, so on balance I've decided I can live with this shortcoming.
Pretty neat!
Focusing on internal development is not a justification for making software proprietary. A software license has nothing to do with development style -- you could do code dumps like Oracle while also licensing the code under a free software license.
> An open-source business that doesn't survive (cough ReplicaDB cough) isn't necessarily better than a closed-but-extensible one that does.
I disagree. All businesses will die eventually (or at least, almost all of them will). The difference between a proprietary business and a free software business is that only one of them actually makes a lasting contribution to society in terms of software (hint: it's not the proprietary one).
> The underlying toolchain (LaTeX and packages) is fully OSS, and isn't going anywhere;
True, and even more of a reason to prefer free software solutions (a proprietary version of LaTeX and packages wouldn't have survived for as long as LaTeX has).
But, each to their own.