One of the results of the Unicode Consortium's work on defining the MessageFormat 2 specification is a data model for messages that's intended to be sufficiently powerful to represent all known features of all known localization formats. Let me show you what it looks like, why this is important, and what you might be able to do with it even if you never use any other part of MF2. Oh, and we're already building open-source tools for working with the data model in JavaScript and Python. Formatting runtimes are available in JavaScript as a polyfill for the proposed Intl.MessageFormat API, and in C++ and Java as a part of this spring's ICU 75 release.