PostNL set out to bring a huge part of their development in-house with a clear goal: hire 150 engineers. However, after onboarding the first engineers, we saw that we needed to become better at onboarding new engineers. Every team was struggling on their own and not sharing their learnings. So we wrote an in-house guide on improving the onboarding for a new DevOps Engineer drawing from everyone's experiences. We want to share this guide focusing on three dimensions: technical, social, organizational. The talk is interesting for onboarding at any company size. It covers typical onboarding points, but puts them in a new light as well as adding additional insights.