Frontend Engineering at Palantir: Building a Backend-less Cross-Application API

This post introduces two new frontend-only frameworks, 'Shared State' and 'Commands', to enable real-time, client-side communication between Palantir applications. Shared State allows applications to define and synchronize data models across tabs, while Commands enables one application to invoke arbitrary logic (APIs) in another. These frameworks are designed to function in DDIL environments by avoiding backend dependencies and are being adopted for direct application-to-application interaction as well as for AIP agents to use as 'tools' to manipulate applications.