Multi-Vendor On-Premises is a self-hosted marketplace builder that allows entrepreneurs to start large marketplaces and scale them easily. Comes with over 500 features, open source code and 1,700 live cases worldwide.
SymmetricDS - SymmetricDS is an asynchronous database replication software package that supports multiple subscribers and bi-directional synchronization.
Dittofi Marketplace Solution - Build a custom marketplace in under 24 hours.
Kettle Pentaho - Pentaho Data Integration ( ETL ) a.k.a Kettle
Sharetribe - Build your online marketplace business. You don't need a developer.
CData Sync - Straightforward data synchronizing between on-premise and cloud data sources with a wide range of traditional and emerging databases.
SmartEngage - Cross-channel autoresponder for marketing automation