At first glance these two software vendors compliment each other well because there is so little redundancy -- Demandware filling a commerce gap in the Salesforce portfolio. However, it’s more complicated than that. From the DX platform angle, Salesforce is acquiring a competitor.
 
Here’s the rub for this acquisition strategy: two platforms divided cannot stand. While Salesforce and Demandware have the benefit of both betting on SaaS, they have big obstacles to overcome. Technology integration and rationalization is one, big obstacle. Possibly bigger, Salesforce’s CRM-centric horizontal roll-up strategy must subsume Demandware’s retail commerce suite, which is a vertical roll-up strategy.
 
Predictions:

• Salesforce must take a firm hand to establish a parallel Commerce Cloud, adjacent to the existing Demandware offering and client base. 
• Perhaps more importantly, Salesforce will leverage the Commerce Cloud in conjunction with Sales, Service and Marketing Clouds to go head-to-head with SAP hybris and Oracle’s CX cloud, and to a lesser extent, IBM. Platform level integration will take time, probably between 12-36 months.