Resilience engineering concepts can complement proceduralization of complex sociotechnical systems (STS). Proceduralization aims at defining precise and quantified system objectives, and at defining a process that describes and prescribes how to achieve those objectives. Although proceduralization has been successfully implemented to capture knowledge and experience, it is limited when the unexpected and unforeseen occurs. Resilience engineering focuses on this drawback and seeks for concepts to enable adaptive responses in these situations. We propose a team reflection process to enhance resilience of a rail STS, complementing its proceduralization. In the present study, we describe how rail signallers used team reflection, supported by a tool that allowed in-depth post-shift inspection of train movements. A near accident, occurring during a one-week observation, is described and used for two purposes. First, it was used as an example to explain the usage of the support tool. Second, it was used as a reference case of topics playing a role in evolving accidents. The analysis showed that the topic categories discussed during the team reflections were similar to the incident categories. This means that relevant topics are available, when things go right, to learn from and anticipate on. In addition, we showed that rail signallers, over the course of the observations, increasingly analysed and reasoned about their work. This enriched knowledge beyond procedures, enhancing the ability to cope with the unexpected and unforeseen.