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Alternative to Google Photos
(lemmy.blahaj.zone)
If it's free and open source and it's also software, it can be discussed here. Subcommunity of Technology.
This community's icon was made by Aaron Schneider, under the CC-BY-NC-SA 4.0 license.
Nextcloud, as mentioned, is a great option but does require a bit of work, albeit not much. I would recommend a Synology server. They're fantastically simple and this was my approach after trying Nextcloud. I did this to divorce myself from Google. Synology has many mirrored services