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The developer preview is essentially a way to run and test the Koinos blockchain framework, which means that it has the 6 critical microservices which can all communicate with one another to produce blocks, containing smart contracts, and then broadcast those blocks over a peer-to-peer network. In addition to modular upgradeability and the microservice architecture, contained within this preview are other innovative features native to Koinos like positive state deltas and active/passive data, both of which will provide massive benefits to vertical scalability.