Abstract: Techniques are described for managing network services deployed in a network using a rules engine with on-demand dependency insertion. A network service manager may use a rules engine to monitor a network service at network devices in order to detect a device-level event, and determine a service-level impact of the detected event based on network service rules and dependencies. The dependencies define links between the device-level event and actions triggered by the device-level event. According to the techniques, a rules engine is configured to detect a device-level event and, in response, insert only those dependencies associated with the detected device-level event into a working memory. Once the device-level event has been cleared, the dependencies related to the device-level event are removed from the working memory. The working memory, therefore, will include only the dependencies needed to determine service-level impacts of currently detected device-level events.