Uppy is a modular, client-side JavaScript file upload library with a companion server (Companion) for remote provider integrations. It provides a plugin-based architecture where core functionality (file selection, upload strategies, UI components) is encapsulated in reusable packages. The client-side library supports drag-and-drop, webcam/screen capture, image editing, thumbnail generation, and multiple upload backends (tus resumable, AWS S3 multipart, XHR, Transloadit). The Companion server handles OAuth flows, remote file listing/download from providers like Google Drive, Dropbox, Box, OneDrive, Facebook, Zoom, Unsplash, and WebDAV, as well as S3 presigning and Transloadit Storage integration. The repository is a monorepo with over 50 packages, including framework-specific wrappers for React, Vue, Svelte, and Angular, plus headless controllers for custom UI. Key entry points are @uppy/core (Uppy class, plugin system), @uppy/dashboard (main UI), @uppy/companion (Express server), and @uppy/aws-s3 (S3 upload client). Data flows: user selects files via UI plugins, which are then uploaded via configured uploader plugins; remote sources are fetched through Companion using OAuth tokens. External dependencies include tus-js-client, AWS SDK, Transloadit API, and various OAuth providers. The codebase is well-tested with unit, integration, and browser tests, and uses modern TypeScript, ESM, and Preact for UI.
ShareX is a comprehensive screenshot, image editing, and file sharing application for Windows. It features a modular architecture with separate libraries for screen capture, image editing, uploading, helpers, history, and tools. The application supports capturing screenshots/recordings, applying annotations and effects, uploading to over 50 services, and includes various productivity tools. Built with .NET/C# using a mix of Windows Forms and Avalonia UI frameworks, it employs MVVM patterns, plugin architectures for extensibility, and cross-cutting helper libraries. The system handles data flows from capture through editing to upload/storage, with history tracking for user convenience.