Vendor lock-in and cloud outages are two importantchallenges that make IT managers reluctant in widely adopting thecloud within the enterprise. Vendor lock-in happens when the adoptionof cloud provider-specific technologies and APIs forces consumers tostay with the same provider even if they would like to change. Cloudoutages can happen to any provider, as the events of the last yearshave largely demonstrated, and have a critical impact on the actualreliability of cloud applications. A solution to both problems couldbe to support application developers and operators in the adoption ofa multi-cloud approach: applications are built to run andreplicate on different clouds, and mechanisms for fast switching froma cloud installation to the other are offered. In the MODACloudsproject we pursue this approach and rely on model-driven developmentcombined with risk analysis and quality prediction. In this paper weprovide an overview of our approach and present the architecture ofthe corresponding platform.