Maybe Pydio, but I haven't tried it. I've heard some good things. Seafile is actively maintained, they just aren't the most ambitious about adding user-facing, major changes. But they do release regularly and add functionality in major versions.
For bare-bones, efficient file-sync, go Syncthing. Want a central server, basic sharing capabilities, basic integration with document editors (OnlyOffice, etc), and excellent sync client performance? Go Seafile. Want lots of features and functionality, excellent sharing capabilties, and tons of third-party plugins? Go Nextcloud and try to optimize it.
I've used Pydio for similar applications in the past, you can set an expiry date for shared files >= 1 day. You can also add a password to shared files, and stop them being downloaded.
In which case, if you want those features but feel you can no longer trust ****Cloud take a look at pydio.
Not used it myself but it looks nice, another thing to evaluate.
http://pydio.com is probably the best software for this. https://pydio.com/en/docs/v6-enterprise/most-standard-case-fs-driver explains how to setup access to a file system. Note they have an enterprise version that provides the ability to remove the copyright links, but is otherwise identical to their open source version.
Currently I have a server with an smb share that is accessed via workstations drive mapping. I then configured a pydio workspace to map to this smb path. Now, when remote, I can login to the pydio interface and get to my files, upload/download etc. Then while at home, I can just use the server via mapped drive.
They have a sharing function built in, where you can limit to a folder or a file, and grant access based on time or on amount of downloads. Screenshot Imgur
I didn't like how Owncloud worked in this regard. Pydio allows me to keep my existing file structure while applying a remote access layer on top of it.
I use pydio. It's easy to setup but requires a database backend. I believe it can use sqlite though. It has some pretty nice sharing features including a download limit.
[edit] Confirmed that it can use an sqlite database stored in the local file structure. Also I updated the url since they've recently redone their site.
If you want a replacement that does not out right not support windows like these two check out a similar system called Pydio. I switched several years ago and have no looked back.
Check out Pydio. It takes some efforts to configure the server side properly, however, the result should totally satisfy you. There is also a PydioSync which is an application that synchronizes files between clients or between clients and server. Here's a link: https://pydio.com/en/products/downloads/pydiosync-desktop-app
In that context there is always pydio mentioned as the third solution (or it may be just my mind to put these three together: owncloud/nextcloud, Seafile and pydio). I never used it so I cannot say anything on the features you requested, but at least their website caters to businesses.
Spideroak is close and would hit all those marks if they would fucking release the rest of their code like they've been saying they would do for years (granted they might have released since I checked last, but I find that doubtful).
Pydio can use ENCFS but not out of the box. Can be a pain to set up too.
For syncthing, you might find this more recent discussion interesting. It's also very close.
You could try out pydio instead of nextcloud. Not as many features such as extensions but man its so much faster. I switched to it because I got fed up with nextcloud and the garbage on it.
I had been investigating Pydio Cells. That solution stores your files as regular files (with the same names) on disk. It would be easy to back everything up, and IMO the website looks much better than Seafile's, but there are no automatic photo uploading clients for mobile devices, and that's a primary use case for many.
Yes I read them. I found https://pydio.com/en/docs/cells/v2/centosrhel-systems, and I was able to get cells downloaded onto my server. However, the installation is not working the way it is described. So, I must be doing something wrong.
For those unaware, it seems Pydio Cells is an online doucment editor/collaborative suite. Replacement for Google Drive(sheets), Dropbox, etc.
Looks like it can be self hosted https://github.com/pydio/cells/
I essentially followed this: https://pydio.com/en/docs/kb/deployment/running-cells-container-behind-traefik-reverse-proxy
However, that doesn't show a MySQL/MariaDB database, so that is different. I also had to change CELLS_BIND=cells.domain.tld:80
to CELLS_BIND=0.0.0.0:80
Are you using a DB container? I can share what I have when I get home.
I have used pydio before, its free and came a as a plugin to install on my namecheap hosting but I know its open souce and I'm pretty sure you can self host. Have a look ! https://pydio.com/
CrushFTP has a web interface. I haven’t used it tho.
Or Pydio, again haven’t used.
https://www.crushftp.com/index.html
Alternatively, how comfortable are you with Linux/CLI? Could use lftp with aliases via SSH, ‘queue mirror —use-pget-n=5’ could be aliased to ‘qm <dir/filename> tab to complete etc.
While it can't do some of those fancy bonus abilities you want https://pydio.com formally known as AjaXplorer, can fit the bill for a simple web file manager. I'm not sure it still does, but it used to let you play flash video and mp3's through the interface. The community edition is, as I understand, only different from the commercial version by it's license.
And what about Pydio? :)
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There is all what you need : On-Premises, all the security features necessary to your need and a free home version.
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Try our live demo to get an idea: https://demo.pydio.com
As an alternative to Nextcloud, you can have a look to Pydio. It's On-premises, powerful and easy to use for you needs. It also has a good design.
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You can try our live demo to make you an idea: https://demo.pydio.com
Check out Pydio Cells! It can be deployed On-premises and offers better performance compared to Nextcloud. We release frequently enough to fix possible bugs and make improvements to make our software as stable as possible.
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Try our live demo to give you an idea: https://demo.pydio.com
Take a look at https://pydio.com/
There are two versions of this software: Pydio 8 and Pydio Cells.
Pydio 8 enterprise support Azure AD and Pydio Cells Enterprise will do too (soon).
An option I would recommend for backups would be borg: https://borgbackup.readthedocs.io/en/stable/
If you want a gui backup solution maybe duplicity + deja dup?
For a folder view: Something like https://pydio.com maybe?