Architecture
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Contracts
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Every interaction on Resource Hub is based on contracts: Everything is a contract!
These contracts are produced by contract procedures. They define the framework of potential contracts. Available payment methods, assets, terms and conditions ...


.. figure:: figures/statemachine-contract-procedure.png
   
   The contract procedure as factory for new contracts

Each individual contract is a state machine. The states represent the different stages that have different actions attached to them. Contracts emit events, that decoupled code can listen to. The change of a state is a very fundamental event emitted by a contract. The audience that listens to these events is called Trigger:  Event -> Condition -> Action

.. figure:: figures/statemachine-state-graph.png

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Service Infrastructure
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Currently the application is deployed in a container.

.. figure:: figures/deployment-architecture.png