sendspin-vst

Sendspin VST3 plugin implemented in Rust.

Compatibility

• Requires Music Assistant 2.8.0b15 or newer.

UI Preview

Current scope

• VST3 instrument plugin with stereo output
• Custom plugin editor (egui) for server selection and status
• Background Sendspin WebSocket client
• Automatic discovery of Sendspin servers
• Timestamped playback scheduling on the audio thread using an SPSC ring buffer
• Underrun-driven sync state reporting (synchronized/error)
• Live diagnostics counters in the editor (queue_overflow, decode_error, late_chunk)

Configuration

Server URL can be configured in the plugin GUI:

• Pick a discovered server from mDNS
• Choose Other... and enter a custom URL
• Click Refresh to re-query mDNS
• Set a custom client name and click Apply Name

A persistent client_id UUID is stored under your user config directory:

• macOS: ~/Library/Application Support/sendspin-vst/client_id
• Linux: ~/.config/sendspin-vst/client_id
• Windows: %APPDATA%\\sendspin-vst\\client_id

Build

cargo check
cargo build --release

Test

cargo test
cargo clippy --all-targets --all-features -- -D warnings

For live server smoke tests (ignored by default):

# In another terminal: start a real server (example using sendspin-cli)
cd ../sendspin-cli
uv run sendspin serve --demo

# Back in this repository
SENDSPIN_SMOKE_SERVER_URL=ws://127.0.0.1:8927/sendspin \
  cargo test network::tests::live_protocol_client_connects -- --ignored --nocapture
SENDSPIN_SMOKE_SERVER_URL=ws://127.0.0.1:8927/sendspin \
  cargo test network::tests::live_smoke_connects_to_sendspin_server -- --ignored --nocapture

To produce an actual .vst3 bundle:

cargo xtask bundle sendspin-vst --release

The bundle will be written to:

• target/bundled/Sendspin.vst3