aspeak is a text-to-speech client for Azure TTS API, written in Rust. It provides a CLI, a Rust library, and Python bindings. The core functionality synthesizes speech from plain text or SSML using either the REST or WebSocket API. The architecture is modular: the library defines two synthesizer types (`RestSynthesizer` and `WebsocketSynthesizer`) with a unified trait, and a CLI wraps these for command-line use. The Python binding exposes a `SpeechService` class. The codebase demonstrates solid Rust engineering with builder patterns, comprehensive error handling, and support for proxies, custom audio formats, and rich SSML options. It is well-tested with unit and integration tests, has CI/CD pipelines, and is actively maintained.