An approach is provided for proactive notification of contract changes in a software service. According to the approach, when the executable code of a composite application operable to access the service is generated, an initial copy of a contract that describes the service is retrieved. A baseline representation of the contract is generated based on the initial copy of the contract. When the composite application is being executed, a determination is made based on the baseline representation whether the contract has experienced any changes. In response to determining that the contract has experienced a change, a notification is sent indicating that the contract has experienced the change.