Ask HN: Dropbox uses Python a lot, is it also the case for their Windows client? | Hacker News Reader

Ask HN: Dropbox uses Python a lot, is it also the case for their Windows client?

2 pointsjosephernest5 comments

It is well known that Dropbox uses (or used) Python a lot for their operation - I have read this quite often here on HN or elsewhere. I imagine this is true for their backend servers.

Question: was their Windows client app mainly done in Python too? (the one that watches the filesystem for changes, stays in the bottom-right system tray icon notification area near the clock, has a GUI...)

If so, which py => exe freeze solution did they use?

How did they prevent the Python bytecode to be decompiled (obfuscation, or compilation in a similar way to Cython? another method?)

Did they open-source some of the tools they developed to make Python perform well as a language that can be distributed as a .exe?

I have tried py2exe and many similar tools, also Cython in embedded mode, and distribution as a .exe is usually not the strength of Python (usual tools work rather well, but sooner or later you find corner cases), so I am curious about the Dropbox company tools for this.

Are there articles about this?

Yes, their desktop clients were mainly written in Python (with Qt) and shared a lot of code between platforms.

Right now I'm looking at their installation folder under Windows. It still comes with python38.dll, as well as a whole bunch of .pyd files. There is some .exe of course, but that could be a small wrapper written in a different language. Anyway, a bundle doesn't make much sense in this case.

Although I can't be bothered to look for sources, I remember reading that they used a quite heavily modified interpreter, at least for obfuscation and optimization purposes.

Some clues can be found on their blog: https://dropbox.tech/application.

Oh this is interesting, I would be super interested to learn about how they embedded Python in their .exe. (Cython can do it, but there are also other ways).

I started reading the blog, but not so much about the packaging of their code into .exe distribution.

I don't expect that to be very special. Embedding Python is a common thing to do, and boils down to using the interpreter as a library: https://docs.python.org/3/extending/embedding.html.

Dropbox has been moving away from Python. A lot of their new backend infrastructure is now written in Go. I don't have any inside knowledge, but it would surprise me if Dropbox ever used Python for their Windows client.

My guess is that it's a .NET executable, and was built using C#.

One way to know if it’s a .Net client is you can run ILDasm or DotPeek against the windows binary and see if it decompiles it.

Reply on news.ycombinator.com