Developer Experience (DX) is the overall interactions and feeling that the developer feels when working towards a goal. It is similar to the definition of User Experience (UX), except in this case the primary user is a software engineer.
Focusing on the three pillars of user experience — usability, findability and credibility — are also excellent markers of measuring developer experience.
For developer experience, having a service that is reliable and performant is key to credibility.
Developer experience is key to building and maintaining the next generation of software and platforms.