I use Ubuntu on a ThinkPad as my daily computer and keep a monthly income-and-expense spreadsheet locally in ONLYOFFICE. At the moment, the file only exists on my laptop and a backup drive, but I may eventually want to share it with my girlfriend so we can both view and update it. She uses a Mac, so switching her to Linux is unlikely.
Google Sheets would make simultaneous editing and access from anywhere easy, but I'm uncomfortable storing a complete record of our finances with a large cloud provider. I considered Syncthing, although that could create conflicting copies if one of us edits the file while the other laptop is offline.
Is there a privacy-conscious solution that keeps the spreadsheet under our control while allowing both of us to access it whenever needed, preferably with collaborative editing?
4 Answers
Syncthing is fine if only one person edits at a time, but it won’t provide true collaborative editing and simultaneous changes can produce conflicts. A shared NAS or private cloud is better when either person needs to open the file independently. Any solution that supports remote access still needs security updates and backups.
A small NAS could work well. Store the file centrally and access it from both computers, possibly through a secure remote-access feature or a self-hosted service such as Nextcloud. You could use LibreOffice on the Mac, though simultaneous editing and conflict handling may depend on the specific setup.
You can use a mainstream cloud drive or Apple’s sharing tools if convenience matters more than keeping the data entirely local. They’ll provide the smoothest access across Ubuntu and macOS, but the spreadsheet will still be stored on someone else’s infrastructure.
Self-hosting a browser-based spreadsheet service is another option if you’re comfortable maintaining a server. That gives you online-style collaboration while keeping the data on hardware you control. Just make sure remote access is secured properly and that you have reliable backups.

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