a proxy core in rust that runs sing-box configs

sbr reads the same configuration files as sing-box and runs them on a core written in Rust. The app for iPhone, iPad, Mac and Apple TV is native SwiftUI around that core, which runs in the system's packet tunnel extension.

why

• faster

  On most encrypted paths measured, sbr moves more data per second than sing-box with the same config file and spends less CPU per byte: trojan over TLS is 14–23% faster on Linux, and WireGuard on Apple silicon uploads at about a third of sing-box's CPU per GB. The benchmarks include the paths where sbr is slower.

• lighter

  iOS stops a packet tunnel extension that uses more than about 50 MB of memory, and Go's garbage-collected heap is why sing-box needs constant tuning to stay under it. sbr has no garbage collector, and a relayed connection costs about 32 KB by default inside the extension.

• harder to block

  Every TLS connection over TCP sends a ClientHello captured from Chrome, Safari or Firefox. Failover notices servers that complete a handshake and then stop carrying data, and a handshake reset before the server answers is retried with its ClientHello fragmented. See features and censorship.

• yours

  sbr connects only to what your profile names. Where sing-box falls back to a third-party default, such as measuring latency against gstatic.com or downloading a dashboard from GitHub, sbr does neither. The app has no account, no server of its own and no analytics; see the privacy policy.

• compatible

  Profiles written for sing-box run unchanged, including remote profiles and rule-sets. A field sbr has not implemented is rejected at import with its JSON path, so a profile never routes differently without saying so.

get it

• iphone and ipad

  In beta on TestFlight. An App Store release is planned.

• mac and apple tv

  Built from source with Xcode; see apple/App/README.md.

• command line

  The sbr binary takes sing-box's flags, on macOS and Linux.

  cargo build --release -p sbr
  sbr check -c config.json
  sbr run -c config.json

Source, issues and documentation are on GitHub.