At Flywire, we have been using blameless postmortem technique for more than 3 years. During that time we have modified, evolved and adapted the process to our company needs. Today postmortems at Flywire are a tool that help us to improve the understanding of our systems, train the oncall team, be transparent with the stakeholders about what happened during an incident, improve our procedures during oncall/fire situations and dig into the root causes of the incidents taking actions over them to fix them and avoid future similar incidents. We want to share which are the principles of blameless postmortem, how we apply them at Flywire and how to start to apply them into your company.