FOSS for encrypted storage container?
I have a bit of data that has to be encrypted and stored into a file so that it can be moved across file systems and possibly OSes. Disk encryption like dm-crypt and a loop device isn't appropriate as it may not exist on another OS.
It's been a very long time since I needed this sort of software. More than a decade ago I used TrueCrypt. I know that VeraCrypt is the current re-incarnationn of the project. Is that still the go-to software for this sort of application? Is there something else that's popular these days?
Veracrypt
Yes highly recommend Veracrypt.
Zip the file(s), then GPG symmetric encryption/decryption with AES. Nothing fancy.
I'd recommend encrypted archives. Like using 7z/7zip to encrypt files.
I use gocryptfs, i like having both CLI for scripts and its got GUI built into KDE Plasma's Vault feature
I personally use Cryptomator, which does on-the-fly data encryption/decryption, allowing you to mount the encrypted data as a "drive" which from the user's perspective looks like any other data drive.