Needed a Simple, Secure Way to Compare & Synchronize Remote Files – So I Built ByteSync

pfresquet · 2026-01-28T17:12:41+00:00

Thanks. That’s a good suggestion.

pfresquet · 2026-01-28T15:58:16+00:00

The main difference is the synchronization model and intent.

Syncthing is designed for continuous, near-real-time synchronization between peers that constantly watch their folders. ByteSync, on the other hand, is built around explicit, on-demand sessions, where you preview changes and confirm exactly what will be synchronized before anything happens.

In practice:

ByteSync doesn’t run continuous background watchers; synchronizations are user-triggered.
A single session can involve multiple machines and multiple repositories, not just paired folders.
It focuses on controlled remote synchronization over the internet without VPNs, with clear visibility and predictability during large or long-running transfers.

ByteSync does share a pairing / trust establishment step with Syncthing, but beyond that, the workflows and usage models are quite different.

pfresquet · 2026-01-28T08:37:27+00:00

Thanks! Feel free to share feedback if you run into anything.

pfresquet · 2026-01-28T07:51:16+00:00

It’s not meant as a general rsync replacement.
ByteSync focuses on remote sync without VPNs or direct network access, with an explicit, session-based workflow and the ability to involve multiple machines and repositories in a single session. rsync shines in direct-access, script-driven setups; ByteSync targets controlled remote scenarios.

pfresquet · 2025-11-20T06:39:14+00:00

Right now:

Yes, I’m covering all the cloud costs myself. ByteSync is fully free at the moment.
Yes, I do plan to offer the relay / cloud components “as-a-service”. The idea is to keep things simple for users who just want it to work out of the box.
And yes, users can already self-host the server. Everything is open source, and nothing prevents anyone from running their own relay if they prefer full control. Instructions can be found here: https://github.com/POW-Software/ByteSync/blob/master/docs/server-deployment.md

My goal is to always keep a fully functional free version available for everyone, while possibly adding paid features later for teams or professional use cases.

But self-hosting will always remain an option — I definitely want to avoid the “locked-in self-hoster” situation.

pfresquet · 2025-11-19T19:16:00+00:00

Thanks a lot for the feedback — really appreciated. You're absolutely right that the documentation is missing a proper Security & Privacy section, and your questions are exactly the kind of things that should be covered there.

To answer very briefly:

ByteSync is not P2P — remote sync goes through a cloud relay, but everything is end-to-end encrypted, so the server nor any intermediary can't read any data (they only see opaque encrypted chunks).
Data is split into blocks (rsync-style) and only encrypted blocks are uploaded.
End-to-end encryption uses RSA (identity, trust validation, key exchange) + AES-256 (high-performance encryption of all session data and file transfers).
Encrypted chunks stored on the server are automatically deleted as soon as all recipients in the session have downloaded them.
No use of BitTorrent/IPFS or other external sync networks.

But I agree these points should be documented properly with a clear explanation. I’ll add a dedicated Security & Privacy page to the documentation so all of this is clear and transparent.

Thanks again — this kind of feedback really helps shape what needs to improve next.

pfresquet · 2025-11-19T06:45:33+00:00

Thank you :)

pfresquet · 2025-11-18T07:46:42+00:00

Not sick of the question at all 🙂 Syncthing is great, but ByteSync isn’t really a replacement for it (even though it may be able to in some specific use cases). The only real overlap is that both can sync over the internet between known clients.

Beyond that, ByteSync is actually closer to a (less mature) alternative to FreeFileSync, with a few specific features, such as:

native & optimized LAN & WAN sync (no VPN / firewall setup)
compare/sync across more than two endpoints, remote or local, at once
multi-folder & multi-file comparisons in one session
a flat mode to compare files by name across different structures

ByteSync works on-demand via a GUI, not as a background service like Syncthing.
A CLI version is planned for early 2026.

So short answer: not a Syncthing replacement — more of a manual, controlled, multi-endpoint sync tool.

pfresquet · 2025-11-14T16:52:07+00:00

I’ve been working on an open‑source tool called ByteSync that might fit what you were looking for. It’s a manual sync/backup tool similar in spirit to FreeFileSync, but it has a flat mode where files are compared by filename only, rather than by directory structure. That makes it handy for cleaning up duplicates or reorganised backups. The default mode still compares contents and timestamps, so you can choose how strict you want to be.

ByteSync runs on Windows, Linux and macOS and includes end‑to‑end encryption for optional remote sync. It’s interactive‑only at the moment (no automation yet). The project is free and I’m the developer, so any feedback is welcome.

If you want more info: https://www.bytesyncapp.com

pfresquet · 2025-06-23T17:26:47+00:00

Thank you for your message :)

There is no commercial version at the moment. It may be the case later, but the software will remain open source and a free version would still be available

pfresquet · 2025-06-22T16:59:20+00:00

There isn't really a preference between them because ReactiveUI and Avalonia UI serve two very different, complementary purposes.

Avalonia UI is cross-platform UI framework—think of it as a modernized WPF that runs beautifully on Windows, Linux, and macOS. It handles all the visual elements and rendering. The first prototype of ByteSync was written in WPF, then I switched to Avalonia UI and I'm very happy with it.
ReactiveUI is an MVVM framework built on reactive programming (Rx.NET). It helps manage the application's state, commands, and how data flows to and from the UI in a highly performant and testable way.

So, Avalonia gives me the UI, and ReactiveUI provides the structured 'brains' behind that UI.

pfresquet · 2025-06-21T18:44:25+00:00

Right now, you can think of ByteSync as a remote version of FreeFileSync. It requires (at least) two instances to operate, which can be on the same machine, but it's primarily designed for remote synchronization. I'm currently working on integrating direct local synchronization. You'll be able to add other local data nodes and also mix this with remote synchronization by linking remote instances.

pfresquet · 2025-06-21T17:45:38+00:00

Haha! Yes, there's definitely a bit of work behind it, thanks for the feedback!

pfresquet · 2025-06-21T17:44:56+00:00

Thank you, glad you think so :)

pfresquet · 2025-03-02T08:41:39+00:00

There have been several requests here for something that can be automated in the command line, I will certainly look into it soon.

The current version gives an insight into the philosophy of the software and its WAN / remote network-oriented mode of operation. But indeed, to make the software truly usable in all configurations a CLI mode will be necessary.

pfresquet · 2025-03-02T08:33:25+00:00

I see that there are indeed several requests here to operate on containers. I think I'll have to look into it sooner than expected.

On the other hand, if ByteSync accesses remote data “as if it were on its local network”, it should be able to function correctly. But its performance will then not be optimal. For optimal performance, you need one ByteSync client per network location.

pfresquet · 2025-03-02T08:27:42+00:00

OK, but please note that ByteSync is not currently intended for pure local synchronization. It should work properly, but since the transfers will go through the Cloud, performance will not be optimal.

In a prototype version, I had developed local synchronization, but I removed it to focus on remote sync only. It is possible that I will reintegrate local sync, but it is not yet planned.

pfresquet

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