AlterSend for Developers & self-hosters.
Open-source, end-to-end encrypted P2P file transfer that works across networks — no LAN limit, no VPN, no cloud storage.
What's slowing you down today
LAN-only tools stop at your network edge
LocalSend and Snapdrop discover peers by local broadcast. The moment the other device is on different Wi-Fi, they simply can't see each other.
The workaround is running a VPN for a file copy
Tailscale or WireGuard makes LAN tools work across networks — at the cost of configuring and running a VPN on both ends, including the other person's.
Cloud sync means trusting someone else's server
Dropbox and Drive solve reach by putting your files on infrastructure you don't control and can't inspect.
Linux is usually the afterthought
Plenty of transfer apps ship Windows, Mac, iOS and Android — then leave the Linux desktop for someone else to figure out.
Getting a 40 GB VM image to a colleague on another network
The same job, before and after.
Before
- Try LocalSend — different subnets, no discovery.
- Set up Tailscale on both machines, and theirs.
- Or upload to S3/Drive and share a signed URL.
- Either way: config, or a third party holding the bytes.
With AlterSend
- Both install AlterSend, pair with a join code once.
- Send the image directly, end-to-end encrypted.
- No VPN, no bucket, no credentials to rotate afterwards.
Why it fits your workflow
Apache-2.0 and auditable
Read the source and verify exactly how key exchange and transfer work. No black box.
Works across networks
Peer discovery over a DHT, not a LAN broadcast — different Wi-Fi, different country, same flow.
End-to-end encrypted, no relay storage
Files travel directly between devices and are never stored on infrastructure in between.
First-class Linux
Linux desktop alongside Windows, macOS, iOS and Android — the same protocol on all five.
Step-by-step guides
LocalSend over the internet
Why LAN discovery can't cross subnets, and what the VPN workaround really costs.
Read the guide →AlterSend vs LocalSend
Same privacy model, without the same-network requirement.
Read the guide →AlterSend vs PairDrop
A native app versus a browser tab and a signaling server.
Read the guide →