Where PeerSync earns its place.

Desktop at home, laptop on the road

Keep your working set identical on both machines without a monthly cloud bill or a quota. At home the two PCs talk directly over the LAN at wire speed. Away from home the laptop reaches the desktop through your rendezvous server, hole-punching when it can and relaying when it must.

• Edit on either side. The newer version wins, the older one lands in the archive instead of being lost.
• Large files only resend the chunks that changed, which matters on hotel Wi-Fi.
• The service keeps syncing on the desktop even when nobody is signed in.

A shared project folder without a SaaS subscription

A design studio, a research group or a small engineering team shares one project tree. Editors hold the read-write key. Reviewers, clients and build machines get the read-only key: they always see the latest state and can never push changes back by accident.

• No per-seat pricing and no admin console to keep in sync with your team roster. A key is the invitation.
• Turn on "Require approval for new devices" and vet each device fingerprint before it joins.
• Peers swarm chunks from each other, so the fifth person to join does not wait on the first.

A live off-site copy on a machine you trust

Mirror your important folders to a PC at a family member's house, a second office or a server in the next building. Give that machine the read-only key: it receives every change but can never write back, so a mistake there stays there.

• The archive on the receiving side keeps deleted and replaced files for 30 days, a safety net against ransomware or an accidental mass delete on the source.
• Continuous, not nightly. Changes stream as they happen, with a periodic rescan to catch what the watcher missed.
• Traffic is encrypted end to end even when it crosses a relay.

Untrusted, encrypted-only peers that store ciphertext without ever holding a readable key are planned for a later phase. Today the receiving PC must be one you trust with the contents.

Pushing builds, datasets and media to a fleet

A CI machine, a render farm or a content team produces large artifacts that many machines need. Publish from one read-write folder and let every receiver join read-only. Receivers fetch chunks from each other as well as from the source, so the source's uplink stops being the bottleneck.

• Content-defined chunking means a rebuilt installer or re-exported video reuses every unchanged block.
• Signed indexes mean a receiver cannot be fed a tampered artifact by another receiver.
• Script it: psp add and psp join slot into provisioning without the dashboard.

Branch offices with your own rendezvous server

Several sites behind their own NATs need to share folders, and the data must not leave the organization. Run the rendezvous service on one Windows Server you control. It introduces peers to each other, helps them hole-punch, and relays opaque encrypted traffic when a direct path is impossible. It never holds a key or a readable file.

• One service, one port (TCP and UDP 99), one TLS certificate. Installer, firewall rules and renewal hook included.
• Health checks, structured logs and aggregate OpenTelemetry counters for your monitoring, with no IPs or folder IDs in the event log.
• Within each site, peers still talk directly over the LAN. The server only matters across sites.

LAN-only sync in air-gapped or offline environments

Measurement rigs, workshop PCs, classroom labs or a studio network with no internet access. PeerSync needs no server and no connectivity beyond the local segment. Peers find each other by multicast and sync over encrypted QUIC exactly as they would anywhere else.

• No license check, no activation, nothing that phones home. It simply works offline.
• Encryption stays on even on an isolated LAN, and discovery tags rotate hourly so a rogue device learns nothing from listening.
• Disable tracker and relay per folder in Folder settings so nothing ever tries to leave the segment.