Anki is a mature, cross-platform spaced-repetition flashcard application. While it is fundamentally an end-user product, it contains significant embedded algorithmic and data-analysis components (FSRS memory-state scheduling, revlog analytics, retention simulation) that make it a hybrid of application and computational research. The production system consists of a Rust backend that owns all core logic, scheduling, SQLite persistence, sync, and media management; a Python Qt desktop frontend (`aqt`); a TypeScript/Svelte web UI for modern editors, graphs, deck options, and image occlusion; and a standalone sync server binary. Communication between languages is driven by protobuf service definitions, with generated bindings for Rust, Python, and TypeScript.
lx-music-desktop is a cross-platform Electron-based music player (Vue 3 + TypeScript) that aggregates multiple Chinese streaming services (NetEase, Tencent, Kugou, Kuwo, Migu, Baidu, Xiami). It provides music search, playback, playlist management, lyrics (including desktop lyric windows and karaoke-style font rendering), downloads with quality tiers, audio effects (EQ, convolution reverb, pitch shifting), cross-device synchronization over a custom WebSocket protocol, and an HTTP Open API for third-party control. The architecture spans three processes: main (Electron window/tray/IPC, SQLite persistence via better-sqlite3), renderer (Vue app with custom reactive stores and a plugin-based audio engine), and renderer-lyric (dedicated always-on-top lyric window). All built-in music sources were removed in v2.6.0 following a Tencent legal complaint; the app now relies entirely on user-supplied Music API scripts, introducing a sandboxed script runtime with security warnings. The repository is actively maintained (last commit 2026-09-19) but the project is in a transition phase—the maintainer has announced a successor project ('Any Listen'), and the codebase shows signs of legacy accumulation: extensive commented-out code, duplicated components (e.g., MusicSortModal), hardcoded API endpoints/signatures that break frequently, and a custom store implementation diverging from Vuex/Pinia. Despite this, the code is well-organized around provider SDK adapters, composable logic hooks, and a clear main/renderer IPC boundary, with several genuinely reusable patterns.