File	Built from	Purpose
`omnivoice-tts-darwin-arm64`	`ServeurpersoCom/omnivoice.cpp` @ pinned SHA	GGUF inference runtime — Apple Silicon
`omnivoice-tts-darwin-x86_64`	same	Intel Mac
`omnivoice-tts-linux-x86_64`	same	Linux (x86_64)
`omnivoice-tts-linux-aarch64`	same	Linux ARM64 — Apple Silicon under Asahi; built with GGML Vulkan where the toolchain supports it, so the Honeykrisp driver can accelerate generation
`omnivoice-tts-windows-x86_64.exe`	same	Windows
`checksums.sha256`	computed by `scripts/build-omnivoice-tts.sh`	SHA-256 manifest — verified by `VoiceStudioGGUFBackend.is_available()`

The pinned commit SHA for omnivoice.cpp lives in backend/engines/omnivoice_gguf/quant_map.json _meta.runtime_commit_sha.

Building locally

scripts/build-omnivoice-tts.sh --platform <slug> --commit-sha <40hex>

See .github/workflows/build-omnivoice-tts.yml build-omnivoice-tts job for the CI matrix that produces these artifacts. Apple Silicon (macos-14) builds cleanly with -DGGML_METAL=ON at the pinned SHA (#2105), enabling hardware-accelerated Metal inference when the packaged artifact passes binary preflight and macOS permits execution. Missing or blocked binaries retain the in-process VoiceStudioBackend fallback.

Placeholder note

Until the CI matrix produces real binaries, this directory contains zero-byte placeholders — a plain git clone always gets those (real binaries ship via the installers / CI artifacts, and are never committed here). VoiceStudioGGUFBackend.is_available() validates the file before trusting it (services/binary_preflight.py: non-empty + a real Mach-O/ELF/PE magic, #1172) and returns (False, "...not a usable executable...") for a placeholder, so the engine reports honestly through the Engine Compatibility Matrix and the default selection falls back to the in-process VoiceStudioBackend. Selecting the engine anyway (e.g. model: "omnivoice-gguf" on /v1/audio/speech) yields an actionable 400/503 naming scripts/build-omnivoice-tts.sh, never a raw "Exec format error".