Motivation
Most audio apps in the market optimize for streaming subscriptions, not local-first long-form listening. Audiobook listeners often want chapter-aware playback, persistent speed preferences, offline reliability, and straightforward file management without account creation or DRM lock-in. Existing tools either hide local workflows behind cloud assumptions or make desktop playback feel like an afterthought.
Spire was built to solve that directly: a lightweight Windows desktop player where local media is the primary path, podcasts are supported as a first-class extension, and user data stays on-device. Making it open source was a product decision, not just a licensing checkbox. The project is intentionally inspectable so users can verify behavior and contributors can improve areas like format handling, playback ergonomics, and import pipelines.
Technical Design
The app uses Electron with a React and TypeScript renderer plus a dedicated main-process service layer. Playback is handled through an mpv integration that communicates over named-pipe IPC, which provides reliable control over time position, pause state, chapter metadata, and playback speed. This choice avoids many limitations of browser-native audio for complex long-form media workflows.
State and metadata persistence are handled with better-sqlite3, including tables for books, files, chapters, progress, bookmarks, downloads, feeds, and settings. The database layer enables durable resume behavior, per-item playback settings, and local statistics without depending on external services. The project uses WAL mode and explicit schema versioning for stable local operation.
Podcast support is implemented through RSS parsing in the main process, with feed metadata and episode entries integrated into the same local listening workflow as file-based audiobooks. The runtime also includes download and library services plus local binary support for mpv and aria2c where needed.
Status
Spire is currently in early access and actively developed in the open. Core capabilities include local library playback, chapter navigation, progress tracking, variable speed control, RSS feed handling, and desktop-friendly control surfaces such as tray behavior and media-key shortcuts. The current focus is hardening import flows, improving playback diagnostics, and tightening multi-format reliability while preserving the same local-first design principles that motivated the project in the first place.