Routines have previously been revealed to be an important design factor in smart homes. However, little research has investigated the utilization of routines in do-it-yourself (DIY) smart home system design. Using routines as a resource for DIY smart homes, this paper suggests the new concept of the smart home system Routinoscope: a routine-driven DIY smart home. Routinoscope is designed to embody collaborative routine reflection among family members. To determine the value of Routinoscope, an in-the-wild study was conducted with 6 households for 3 weeks. The results show that unlike the previous DIY smart home systems, Routinoscope shows different types of user experiences. Routinoscope enabled sensitivity to daily problems and better mediation between routines and smart home features. It also allowed family members to share their conflicts and help each other reduce such conflicts. Based on the findings, 2 design implications for future DIY smart homes are suggested: providing a problem-finding method and considering routine changes over time to maintain the DIY smart home.