qurb

Private cloud storage. Dropbox-like sync where your files stay on your own devices — they move directly between them, encrypted end to end, and are never stored on our servers.

Status (2026-10-19): working on Linux and Android, both apps designed, in light and dark. A computer backs up a phone's WhatsApp and chosen folders, and keeps a folder for each person, opened with a yes on their phone. Release 0.1.0 is built — Linux, Android on every ABI, and Windows, which has not run on Windows — and not yet published (docs/releasing.md).

• The engine is complete and hardened: two devices sync end to end over QUIC, with encryption, conflict handling that never discards an edit, and key management — verified at 100,000 files, and tested against crashes, wrong clocks, long absences, damaged disks and hostile peers.
• The desktop window does everything the command line does: setting up, pairing by QR code or six digits, browsing and freeing files, sending to one device, recently deleted, settling conflicts, sharing a folder with chosen devices, keeping a folder only remotely, and a passphrase on the key. Files opens on Shared and a folder for each person — each phone's WhatsApp, backed-up folders and Private Vault — opened only with that person's yes on their phone. Designed to the owner's direction, light and dark. There is an Arch package.
• The Android app syncs with a laptop both ways, from home Wi-Fi or mobile data, is woken by push within seconds, takes shares from any app, and shows its files in the system file picker — verified on a Galaxy S23. It backs up WhatsApp (36,062 files, 10.1 GB on the S23) and chosen folders to the laptop, and reaches its folder there to download or restore a file.
• Not done yet: the relay running on a server, publishing the release, iOS and macOS, and running Windows at all. Restoring WhatsApp from the laptop is unproven. Unmeasured: battery over a day on a phone, and how often a direct connection works across other networks.

docs/features.md lists everything that exists, and how far each piece has been checked.

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Start here

docs/CODEBASE.md — everything needed to understand this project from scratch. No prior context assumed.

Then, depending on what you want:

you want	read
what it can do today	docs/features.md
the vocabulary	docs/glossary.md
what comes next, and what the product brief asks	docs/product-plan.md
the phases, and the honest risks	docs/roadmap.md
the full target design	docs/architecture.md
why a particular choice was made	docs/decisions/
what each phase produced and measured	docs/phases/
how to try it on your own hardware	docs/trying-it.md

Layout

docs/           documentation — start with CODEBASE.md
crates/         the engine, the program, the desktop window, the services
android/        the Android app, a thin Kotlin layer over the FFI
packaging/      installing: an Arch package, an install script, server units, Windows' README
scripts/        building for Android, a release, generating bindings and icons, the desktop smoke test
experiments/    throwaway spikes, clearly marked as such
website/        the website (Next.js), in the apps' design, independent of the engine

The split between crates/ and experiments/ is deliberate. Experimental code may cut corners provided its README says which. Code in crates/ is meant to last. Nothing migrates silently between them.

Trying it

From a release (./scripts/release.sh builds one into dist/; what each file is for, and what it has run on, is docs/releasing.md): the .deb on Debian, Ubuntu and their kind, the .rpm on Fedora and openSUSE Tumbleweed, both for glibc 2.34 and later; the Arch package; the static qurb alone on any Linux; the .apk on any Android phone from 8.0.

From this checkout, on Arch — the window, the tray icon and the command line:

cd packaging/arch && makepkg -si

Anywhere else, for this user only:

cargo build --release -p qurb-cli -p qurb-tray -p qurb-desktop
./packaging/install.sh

Then open qurb from the applications menu: it sets the device up — nothing to write down — and pairs another device by QR code or six digits. From a terminal instead:

qurb init                  # a new key, in ~/qurb/Shared; nothing to write down
qurb pair                  # on it: shows a code and six digits
qurb join <code or digits> # on the other device: takes the key and pairs
qurb run                   # on both

The Android app: ./scripts/android-app.sh install. Syncing from outside the house needs the rendezvous service reachable from both devices — docs/anywhere.md. Step by step, including the phone: docs/trying-it.md.

To watch the whole system work in one process, servers included:

cargo run --release -p qurb-peer --example demo -- /tmp/device-a /tmp/device-b

Building and testing

cargo build --release
cargo test --workspace         # 879 tests in 94 binaries, all passing (2026-10-15)
./scripts/desktop-smoke.sh     # the real window, driven end to end

The Phase 0 measurements — chunking throughput, boundary stability, NAT classification — are in experiments/phase0-spike and docs/phases/phase-0-spike.md. quictest stun there contacts public STUN servers, revealing your public IP to them as any video-call client does.

Licence

Either of Apache-2.0 or MIT, at your option, as Cargo.toml declares.