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Altersend
File transfer with no cloud storage, no account, no limits
96 followers
File transfer with no cloud storage, no account, no limits
96 followers
AlterSend sends files directly between devices - P2P, E2EE, no cloud storage, no account, no size limits. Open source and cross-platform: mobile + desktop. Share a code or scan a QR, and files stream straight across.
Altersend
Hey Product Hunt! 👋
I'm Denis. I built AlterSend because sending a big file to someone is still way harder than it should be. You upload it to WeTransfer or Google Drive, wait, hit a size limit, send a link, and your file ends up on a server that isn't yours. It's slow, it's capped, and it's not private.
AlterSend sends files straight from your device to the other person's. No upload step, no account, no size limit, end-to-end encrypted. Works anywhere - same room or another country.
We released a month ago and it's going better than I hoped: 7,000+ downloads, almost 1,000 GitHub stars, and a lot of great feedback from users that's helping me decide what to build next.
How it works:
• Each transfer creates a random 32-byte key - that's the join code you share with the receiver
• Devices find each other through a public DHT using a hash of that key - the key itself never leaves your devices
• The connection is encrypted end to end. If a direct connection isn't possible, a relay passes the encrypted stream along - it can't read your files and doesn't store anything
• When you disconnect, everything is wiped — nothing is stored anywhere
It's open source (Apache-2.0), free, and there are no accounts.
I'd love honest feedback - especially: what would it take for you to stop using WeTransfer, Drive links, or USB sticks? I'll be in the comments all day. 🙌
the "your files never touch the cloud" pitch is solid on paper but real P2P is never that clean once both sides are behind restrictive NAT/CGNAT - like on separate corporate wifis. what happens then, does it fall back to a relay server (still E2EE, just not direct), or does the transfer just fail and you're back to a USB drive?
Altersend
@galdayan yes, if hole punching fails (CGNAT/NAT), it falls back to a relay server. But the relay has no idea what your file is, it just forwards encrypted bytes.
@denisdev good, that closes the loop for me. one more - is the relay something you run and pay for yourself, or a third-party TURN service? for the "no cloud, nothing stored" pitch to hold up under the fallback path too, I'd want to know whose infra is passing my bytes along even if it can't read them
Altersend
@galdayan it's our own relay we run ourselves, but the plan is to let you self-host your own relay, or offer a dedicated one if you need better throughput and bandwidth.
@denisdev fair enough, that's a reasonable answer for a solo/early project. self-hosting the relay - is that already something people are running today, or still on the roadmap? asking because for a team that wanted the "no cloud" guarantee to be literal, being able to point the app at their own relay from day one would matter more than the fallback quality itself
How do you handle firewall and NAT traversal in the peer-to-peer file transfer process?
Altersend
@aymnart
We use Hyperswarm for discovery and NAT traversal, public bootstrap nodes help get the first peers introduced, then the DHT helps them hole-punch a direct UDX connection to each other, and only when that can't work (symmetric CGNAT, VPNs) do we fall back to an opt-in blind relay that blindly forwards encrypted bytes.
@denisdev The way you've implemented Hyperswarm for peer discovery is really impressive.
Connecting devices is near-instant! and file transfer is fast!
I just Downloaded it for my linux and android devices and decided to keep it.
Good luck! looking forward to more UX improvements.
Altersend
@aymnart thanks for it ! Will definitely keep improving it
Denis — the Hyperswarm + blind-relay fallback you explained to Aymen above is a clean answer to NAT. The harder case I run into with WinBidIQ's audience (SMBs teaming up on federal contract bids) is government and defense-contractor networks that don't just sit behind NAT — IT policy actively blocks outbound P2P/DHT traffic at the firewall, full stop. Does AlterSend's traffic pattern look enough like ordinary HTTPS/WebSocket to get through a typical corporate proxy allowlist, or is a network locked down like that just a hard no regardless of the relay fallback?
This looks really clean, love that there's no account or size limit involved. One thing that would make it way more usable for me is the ability to resume an interrupted transfer if someone drops off wifi for a second, since flaky connections mid-download are the worst.
Direct transfer usually means both devices need to be online at once. How do you handle sending something to someone who isn't around until later, or is that out of scope by design?
Almost everybody is logged into google drive and I see that the difference between AlterSend and Drive is that nothing gets stored. It's great but there's also a downside if someone wants to delete the file later, how often does that happen ?