Our work with legacy code doesn’t often put us in a position to move quickly into new or trendy tooling. And while we almost always introduce Docker very early in our projects, it is usually only for the purpose of standardizing and easing setup of developer environments. Transitioning a live environment to containers, however, can be a daunting prospect.

There are a variety of reasons for that, many of which you’ve probably encountered yourself, which include:

1. The application isn’t in the cloud yet
2. It’s too complicated
3. Container orchestration (like Kubernetes or Swarm) is too new/buggy/insecure
4. We need microservices to leverage Kubernetes
5. The application is a monolith

All these might be valid reasons, but this talk will focus on our experiences in that last scenario — containerizing a monolith.