To Crd, or Not to Crd, That is the Question

One of Kubernetes most promising features is the ability to extend its API via use of Custom Resource Definitions (CRDs). As such, it comes as no surprise that CRDs have recently seen a big rise i …

One of Kubernetes’ most promising features is the ability to extend it’s API via use of Custom Resource Definitions (“CRDs”). As such, it comes as no surprise that CRDs have recently seen a big rise in popularity. But what exactly makes CRDs so great? And, more importantly, when should you be thinking about using them? Whilst Kubernetes Operators are often cited as a main use case for CRDs, their use is evolving into something much more exciting. Now, not only are developers extending the API with customizations for their Kubernetes clusters, but we are starting to see them making use of CRDs to build their applications! This is something that both Sam and Ed have been thinking about for a while now. In this talk they present their learnings by discussing the relative merits and drawbacks of a CRD-based approach to application development compared to more traditional approaches.