Gekko 2.2 is now (summer 2018) available in a stable version, and a stable version 2.4 is planned for release in the summer 2018..

Development-wise, the main part of the Gekko development in 2017/18 has been on the up-coming Gekko 3.0, with syntax clarification, richer data objects, GAMS-like sets and array-timeseries, and many new features. Version 3.0 is planned for release in the autumn 2018. The syntax changes will not be dramatic, and an automatic translator from 2.2/2.4 is planned.