Magic Wormhole: Get things from one computer to another, safely

by xd1936on 10/2/25, 12:25 PMwith 102 comments
by vu3rddon 10/6/25, 11:10 AM

My friend and former colleague has built a bunch of stuff over magic-wormhole like fowl[0], shwim[1] and so on. There is a lot of nice work on "dilated" wormhole.

[0] <https://github.com/meejah/fowl>

[1] <https://github.com/meejah/shwim>

by jerrythegerbilon 10/6/25, 2:48 AM

And its lesser known component, the mailbox server used for signaling to connect the two computers. If you’ve ever installed and used magic wormhole, you’ve likely used the default public mailbox server unless you configured and set up your own.

https://github.com/magic-wormhole/magic-wormhole-mailbox-ser...

by mikae1on 10/6/25, 5:34 AM

croc[1] has worked better for me. It supports resuming transfers, which is a must. It is very wormhole like and written in Go.

[1] https://github.com/schollz/croc

by brendynon 10/6/25, 4:11 AM

This project made me learn about and attempt to implement the SPAKE2 protocol and HKDF as an exercise. It's quite fascinating. It lets you upgrade a short password to a long key, but requires trusting a server to rate limit attempts on brute-forcing that short password. It seems difficult to find a practical use case for it tho. Because it's only relevant when it is impractical to send a long key. But if you think for a second, lets say you are transferring from a desktop to a phone, you can show a QR code and scan in with your phones camera, thus achieving a secure handshake bypassing the need for SPAKE2 all together. Maybe it would defeat the simplicity of the tool, but if it also provided a long string of words for the key, a user could optionally send all the words instead of just the first few and get themselves a secure key without needing to trust the server.

by rahimnathwanion 10/6/25, 5:03 PM

For sending files between my phone (Android) and my son's iPad, I use:

Wormhole William (Android): https://github.com/psanford/wormhole-william-mobile

Destiny (iOS): https://github.com/LeastAuthority/destiny

For interoperability, don't use Destiny's default servers. After you install Destiny, change the config to the standard Magic Wormhole servers:

Mailbox: ws://relay.magic-wormhole.io:4000/v1

Transit Relay: tcp://transit.magic-wormhole.io:4001

by smusamashahon 10/6/25, 3:33 AM

https://gist.github.com/SMUsamaShah/fd6e275e44009b72f64d0570... List of p2p file sharing tools including this one. Most in the list are browser based.

by klysmon 10/6/25, 3:42 AM

I use this all the time when trying to get files between devices that need multiple hops to get to. Way easier then remembering what scp or rsync combo I need to jump through a host

by remramon 10/6/25, 3:07 AM

AFAIK, Web Wormhole is the only one of those tools that can be used both as a command-line tool and from a browser. It looks like the site is down at the moment though. https://github.com/saljam/webwormhole https://webwormhole.io/

by FireInsighton 10/6/25, 4:02 AM

I prefer https://localsend.org/ nowadays. Nice cross-platform GUI, "just works". Requires being on the same lan, but discovery of other devices is automatic and there are no alphanumeric codes that have to be shared. It's a good QoL improvement to have "airdrop" between Android and Linux

by 0xDEAFBEADon 10/6/25, 7:31 AM

>Copying files through encrypted email requires bootstrapping a GPG key as well as an email address.

Do people realize that GPG supports symmetric encryption?

by burnteon 10/6/25, 4:29 PM

One of the best tools I've ever used. I adore it. I use it everywhere. It's supremely handy when migrating data between servers in a hurry.

by Uehrekaon 10/6/25, 5:44 AM

I’ve used this and localsend, both are great, but has anyone finally solved the problem of making one of these things that can use a GUI (for phones and tablets) and also a CLI (for when I’m SSHed into my home computer and need to send a video to get processed by something)?

by ignoramouson 10/6/25, 12:05 PM

Folks at Coder authored a p2p file transfer tool using Tailscale (no account needed, the setup is entirely ephemeral, and the code apparently runs a Headscale control server in-memory): https://github.com/coder/wush

Unsure how Tailscale rate limits, if at all, such traffic flowing through its public relays ("DERP"), as a tool like this is just ripe for abuse?

by nine_kon 10/6/25, 2:56 AM

A simple encrypted channel for file transfer. A great way to send a file to a stranger who is near you but shares nothing with you, e.g. at a conference.

/* A modern version should, of course, work in a browser, so that there'd be no Python packages to install. But the browser security model does not allow listening, so a signaling server would be needed to create a WebRTC connection. It could run on one of the devices involved, but still can't be a pure web app. */

by BinaryIgoron 10/6/25, 3:49 PM

Been using it from time to time to transfer secrets; out of curiosity, when I'm sending something to some via this tool, do you known what machines is it relayed through? I am sure it's not peer-to-peer; would not be as reliable!

by AAAAaccountAAAAon 10/6/25, 10:07 AM

I did use it some time ago, but I remember the user experience being somewhat confusing, since there are multiple similarly named tools around, which don't seem to be interoperable. Still, a cool concept.

by AnonHPon 10/6/25, 3:12 AM

I’m glad to see that there are mobile apps and web applications that work on/use Magic Wormhole for peer to peer file transfers. The mobile app and web applications seem to be limited (number of files is one at a time, size of file allowed, etc.) due to limitations on mobile platforms and due to choices by the developer/server host.

by Arubison 10/6/25, 3:10 PM

Strong recommend. When I’m bouncing around getting onboarded on new client/customer machines that disallow syncing (justifiably), magic wormhole is a fabulous way to get my dot files and local env set up in a jiffy. Works well for secure transfer of _large_ files ad hoc, too, so a great fit for db dumps.

by samuelon 10/6/25, 10:19 AM

Recently learnt about tailscale funnel, and I love it, I would use for everything.

tailscale funnel --set-path <secret> <DIRECTORY>

(The path is needed because there are lots of bots who scan tailscale hostnames).

This works if the sender is tech savvy (and a tailscale user) but not in the other direction.

by aborsyon 10/6/25, 3:52 AM

I use magic wormhole when I first install a computer to send an SSH key. At that point, I have ssh. Also if you use a mesh VPN, your devices are already connected and there are several ways to transfer files.

I like to use it more. What is your use case for this?

BTW, I haven’t found a good iOS app.

by deknoson 10/7/25, 6:30 AM

1. i wish syncthing also would implement this 2. is it already postquantum secure?

(to all the quantum-computer-will-never-come-people: i like to be prepared in CASE it comes, otherwise no one will prepare and users are in the dust, once it is there)

by catlifeonmarson 10/6/25, 1:52 PM

Maybe I’m missing something but has this been largely superseded by wireguard these days?

by benoliver999on 10/6/25, 9:49 AM

I use this very specifically for setting up new machines. It's one of those where I don't use it much, but when I do it has saved me a whole lot of time, and it's worked well every time.

by ternon 10/6/25, 8:02 AM

Don't want to crash my friend's server, but he made a Mac app with this: https://www.viawormhole.xyz/

by jedisct1on 10/6/25, 7:51 AM

I use Piknik: https://github.com/jedisct1/piknik

by standup75on 10/6/25, 4:53 AM

I use it all the time. this tool is so great

by cloudkingon 10/6/25, 3:18 AM

Another simple solution works on LAN https://pairdrop.net/

by peterhadlawon 10/6/25, 2:38 AM

It just works.

by wslhon 10/6/25, 11:55 AM

Great tool.

Very minor web page issue report: please add a replay to the video. Thanks.

by etc-hostson 10/6/25, 6:20 PM

can Magic Wormhole help me place a directory of a terabyte of files onto multiple hosts in a datacenter ?

by vismit2000on 10/6/25, 7:01 AM

Another cool solution: Copyparty – Turn almost any device into a file server https://news.ycombinator.com/item?id=44711519

by humanfromearth9on 10/6/25, 2:12 PM

How better than Syncthing is it?