Chemsex among gay, bisexual and other men who have sex with men (GBMSM) has received increasing attention as a public health concern in recent years. Chemsex can affect a variety of aspects of the lives of GBMSM and contribute to physical, social and emotional health burden. Starting from a continuum perspective of chemsex, rather than a binary view of problematic vs. non-problematic use, we argue that men engaging in chemsex at different points in their chemsex journey may benefit from tailored and personalized support to cope with the various and evolving challenges and concerns that may be related to their chemsex behavior. To date, interactive digital communication technologies are not much used to provide support and care for GBMSM engaging in chemsex, neither for community-based support and care nor by health services. This suggests potential for missed opportunities, as GBMSM are generally avid users of these technologies for social connections and hookups, including in relation to chemsex. Recent research has provided emerging evidence of the potential effects of so-called just in time adaptive interventions (JITAI) to provide effective support and care for a variety of health issues. JITAI hold much promise for the provision of appropriate, tailored support and care for GBMSM at different points in the chemsex journey. Co-designing JITAI with potential users and other stakeholders (co-design) is key to success. At the Institute for Tropical Medicine, in Antwerp (Belgium), we initiated the Chemified project to develop an innovative digital chemsex support and care tool for GBMSM. This project illustrates how current understanding of chemsex as a journey can be integrated with a JITAI approach and make use of co-design principles to advance the available support and care for GBMSM engaging in chemsex.