rep_lang is a custom-built language for reaction and reputation data. It aims to provide an extensible framework for Neighbourhoods to specify "types" of responses and event records which are important to them, define functions over those types, and instantiate data values of those types. rep_lang makes "shared computation" seamless and facilitates easy sharing and remixing of these types, functions, and data definitions between agents and communities. By doing so, it will support the translation of social sensemaking metrics from one context to another.