baud

Messages with no server in the middle.
baud.rubric.sh · How it works · Mac · iPhone · Android

baud is a messenger for chats, groups and calls. Your messages go straight from your devices to your friends' devices. When there's no direct path, a device of yours or of a friend carries them, sealed, until the other side is back. There is no account, no phone number, and no company server that sees who you talk to.

How it works

• You are a key. Each device makes its own key pair, and your devices share a person key that signs your name and device list. Nothing is registered anywhere.
• Friends meet by link. A link or QR code works once, for an hour, and carries everything needed to connect after the #, so no server sees it.
• Direct whenever possible. Devices connect over QUIC (iroh), IPv6 first, and get through routers with port mapping and hole punching that a mutual friend's device coordinates. No public relay or discovery server is involved.
• Friends carry the rest. When two devices can't reach each other, a trusted device (yours, or a friend's) forwards the encrypted packets or holds a sealed envelope until the recipient is back.
• Your address stays with people you chose. Strangers can't connect to you and never learn your IP.

One small server exists: the wake relay, which asks Apple to wake a sleeping iPhone. It never sees a message and keeps nothing. docs/protocol.md covers the whole design, what each party can see, and the current limits.

What's in here

Folder	What it is
peer/	The network: identity, links, finding devices, hole punching, relays and carrying. Rust, on iroh.
core/	baud's Rust core: conversations, sealing, sync, files, calls. Used by the Android app.
BaudCore/	The same core in Swift, for the Mac and iPhone apps.
apps/	The apps: mac, ios and shared (SwiftUI), android (Kotlin, Compose), icon.
wake/	The wake relay for iPhones. A single Rust binary.
site/	baud.rubric.sh, a static site.
docs/	How the network works, and notes for working on baud.

Build it

You need rustup (stable), and for the apps Xcode 26 with XcodeGen, or Android Studio with the NDK and cargo install cargo-ndk.

# The network, the core and the wake relay
(cd peer && cargo test --workspace)
(cd core && cargo test --workspace)
(cd wake && cargo test)

# Mac and iPhone
peer/scripts/build-swift.sh            # builds the network for Swift (peer/swift/PeerKit)
xcodegen generate
xcodebuild -scheme BaudMac -destination 'platform=macOS' CODE_SIGNING_ALLOWED=NO build
xcodebuild -scheme Baud -destination 'platform=iOS Simulator,name=iPhone 17 Pro Max' CODE_SIGNING_ALLOWED=NO build
(cd BaudCore && swift test)

# Android (JAVA_HOME can be Android Studio's bundled JDK)
(cd apps/android && ./gradlew assembleDebug)   # builds the Rust core for the phone first

To see the app without a network, run the Mac build with BAUD_DEMO=1. It puts three demo people on an in-process mesh around you, with chats, a group and a space. docs/development.md lists every switch and script.

Status

baud is at version 0.2.19, for Mac, iPhone (a TestFlight beta) and Android, from baud.rubric.sh. It has not had an independent security review. Read the limits before you rely on it.

License

Public domain, under the Unlicense. Do whatever you like with it. Vendored and third-party pieces keep their own licenses, listed in LICENSE.