Arcmark is a native macOS bookmark manager designed to attach to any browser window as a sidebar, providing a workspace-based organization system for bookmarks. It is heavily inspired by Arc Browser's sidebar and operates as a local-first application.

The product offers browser sidebar functionality that attaches to Chrome, Arc, Safari, Brave, or any browser window. It includes workspace organization with separate bookmark collections using custom-colored workspaces, nested folders with hierarchical structures created via drag-and-drop, and inline editing for renaming folders and links directly in the list. Additional features include search and filter capabilities to quickly find bookmarks across workspaces, automatic fetching of website icons and page titles, browser import functionality from Chrome or Arc browser, and an always-on-top mode to pin the window above other applications.

Arcmark stores all data locally in a single JSON file on your Mac, emphasizing privacy and control. The application is built using Swift and AppKit frameworks, ensuring native macOS integration and performance.

Benefits include improved bookmark organization through workspace separation and hierarchical folders, enhanced productivity with quick access and search features, and data privacy through local storage. Use cases involve managing research materials, organizing project references, and maintaining personal browsing collections.

The target audience includes macOS users who need efficient bookmark management across multiple browsers. It integrates with Chrome, Arc, Safari, and Brave browsers, and is open source under the MIT license.