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.
AssetSync is a Ruby gem that synchronizes compiled assets from a Rails (or Rack) application to cloud storage providers such as AWS S3, Rackspace Cloud Files, Google Cloud Storage, Azure Blob, and Backblaze B2. It hooks into the Rails asset pipeline by enhancing the `assets:precompile` Rake task, automatically uploading assets after compilation. The gem supports incremental uploads (uploading only new or changed files), optional deletion of obsolete remote files, gzip/brotli compression, concurrent uploads, CDN invalidation, and caching of remote file lists for performance. Configuration is flexible via Rails initializer, YAML file, or environment variables. The codebase is well-structured with a clear separation of concerns (`Config`, `Storage`, `MultiMime`), comprehensive unit and integration tests, and support for multiple Rails versions (6.1 through 8.1) and Ruby versions (3.0+). It is actively maintained with recent releases and zero Dependabot alerts.