Oval – Native macOS client for Open WebUI with on-device voice mode

Hey HN, I built Oval because I use Open WebUI as my self-hosted ChatGPT alternative but missed having a proper native Mac app for it.

What it does:

- Native SwiftUI macOS client that connects to any Open WebUI server

- On-device voice mode — STT and TTS run locally via RunAnywhere SDK (Whisper ONNX or WhisperKit on Apple Neural Engine), only the LLM call goes to your server

- Realtime transcription with speaker diarization (FluidAudio — Pyannote + WeSpeaker, all on-device)

- Sparkle auto-updates, keyboard shortcuts, floating voice panel

Why on-device voice?

Privacy — your audio never leaves your Mac. Latency — no round-trip for STT/TTS. And it works offline for transcription.

Stack: SwiftUI, RunAnywhere SDK (sherpa-onnx + WhisperKit), FluidAudio for diarization, Socket.IO + SSE for chat streaming.

Would love feedback, especially on the voice pipeline architecture.