> Can someone clarify if they mean development environments, or if they're talking about a service that they sell that's related to development environments.

their question isn't asking anything. It's both about development environments AND a service they sell, which is dev envs.

Even so

> This is the story of how (not) to build development environments in the cloud.

that is what the article is about. Their words. The person asked what the article is about, this it it, from the authors themselves.

read the damn article