Continuous software engineering copes with frequent changes and quickly evolving development projects while maintaining a high software quality. Developers require knowledge about former and ongoing decisions as well as about the users' needs to evolve software. Thus, decision and usage knowledge are two important knowledge types in continuous software engineering. Issue tracking and version control systems are widely used in continuous software engineering but lack a structured approach to integrate decision and usage knowledge. In this paper, we present ideas and requirements for a tool support to manage decision and usage knowledge in continuous software engineering. As a first step, we introduce the JIRA DecDoc plug-in for documenting decision knowledge.