So, let me summarize everything that I’ve figured out so far:

• There is a detailed breakdown of the optional features of all supported storage providers in the Rclone documentation, including public sharing links feature. Exactly what I was thinking about. So my initial search has now narrowed down a bit. I like how no one even tried to dig in that direction :D I appreciate you pushing me towards the hard-selfhosting path, though! Community name checks out, as they say…
• AFAIK all dynamic DNS services work like this: you install a daemon on your PC (or router), it connects to the DDNS provider’s server. That server looks at the source IP address of your request and then puts it into the A record of the domain name they provide you. So it won’t work with reverse-proxying daemons like Cloudflare Zero Trust or Netbird, at least not directly.
• On the other hand, these reverse-proxying solutions (TIL it called ZTNA — Zero Trust Network Access) has an option to use it with external domains. Their documentation mentions that you should set a specific CNAME record for your domain. However, Cloudflare supports this setup only on the paid plans! So it turns out that Cloudflare Zero Trust isn’t suitable for this task at all.
• And just out of curiosity: does Cloudflare shows the same obnoxious browser check page in front of a service behind its Zero Trust? And will it even work with a non-browser client in that case, like Nextcloud client? I know that you can set up a split-horizon DNS (such a cool name!) to open your service from within your network, I’m just curious.
• Seems like Netbird allow you to use external domain for free with their gateway. Finally, good news! You still need a DDNS provider that allows you to set CNAME record for a free domain name, though. No-IP, however, provides this option only for their paid domains. So it also isn’t suitable for this task. Are there any DDNS providers that allows you to set CNAME record for free?

Am I missing something? Also, hope you don’t mind me overexplaining like that! It’s pretty much notes for myself, but you never know if it might be useful for someone else.

Well, while it’s probably the most sane solution, it doesn’t suit me at all, unfortunately. For me, there is a strict requirement: it must be free of charge, without any payment at all. Guess I should have mentioned it explicitly in the original post, but I did not expect such an immediate direction shift!

Basically the S3 API allows authenticating with a signature as a part of the URL that are scoped to a specific object and optionally expires.

I see, like that, right? But it says expiration is rather mandatory than optional, and these pre-signed links lasts no longer than 7 days! Or is it just an Amazon’s own limitation, and other S3-compatible providers might provide unlimited expiration time?

I know Yggdrasil, it’s pretty cool! But if I’m about to ask my audience to install some additional software, I’d rather prefer ZeroNet, as it provides built-in P2P redundancy and doesn’t even depend on my host being alive. So it likely fits better with my initial idea. Although I really don’t have confidence to ask for this, unless this hypothetical software is purposefully tailored to my use case. And for now, It doesn’t exist (yet?).

Interesting… I didn’t even think it could be used that way! So I might as well consider this option for real. Can it be used with a dynamic dns TLD?

Don’t feel brave enough to selfhost a public-facing service, though…

And… how to obtain a public IP, then?

because unencrypted http is BAD.

Sorry, I don’t enjoy such blatant wordings at all. I prefer to say «supports delivering content unmodified solely by a lucky chance» :D

Edit: now, after reading @[email protected]’s and @[email protected]’s comments, I realized that Cloudflare tunnel could be used for reverse-proxying traffic to the local daemons! You know, when you think about Cloudflare, you genuinely feels nothing but repulsion after all that endless browser check pages, and don’t even consider it as something useful. So for now, I’m trying to wrap my head around all of this to ask a meaningful question. So it’s not over yet!

I know, right? But it requires a valid TLD and a public IP, so this is not an option, unfortunately.

That’s exactly what I’ve imagined after reading the original post, thanks for sharing!

In theory anything that can host WebDAV, SSH/SFTP, or an S3 endpoint would do the job.

Sounds like Rclone, which can host all of these protocols, has a web UI, and can act as a REST server for Restic as well. Haven’t tried it yet, though! Just leaving it here as an additional option to consider.

Yeah, I think that must be it. So it wasn’t a déjà vu! Thanks for the clarification.

By the way, is there any good place to ask for help if I’d like to request a modding tool for certain niche games? I have almost no idea about reverse engineering, so I’m unlikely to do it myself, even with LLM assist.

«It’s all your fault!» — Sony to Sam Altman, probably

Also, I have a strange déjà vu: wasn’t there a native Bloodborne recompilation a couple years ago? I remember watching a few videos about it. If I recall correctly, there was a strange cape animation, as it’s internally rendered in 30 FPS, or something like that. Or was it an emulator?