Mystique CLI is an Atlassian developed CLI for Optimizely Web. It is a multi-phase project that is currently focusing on improving the development cycle for growth engineers. Currently, Mystique is the standard for developing web experiments at Atlassian, and is capable of a wide variety of operations utilizing Optimizely's REST API. This includes creating, updating, testing, and duplicating experiments/personalization campaigns, as well as "promoting" these entities between Optimizely projects for different environments (e.g. from QA => Prod). It has significantly reduced manual overhead and decreased development time by up to 95% for particular actions.