What do you like best about the product?

The platform and API documentation are stellar; kudos to the GraphQL explorer as well!
Utilizing clusters and having a webhook and notification service built into the platform has eased some previous pain we've experienced.
The web UI and UX are very intuitive, and pairing them with the amazing docs makes for a pleasant product introduction.

What do you dislike about the product?

Mostly a personal gripe; creating a YAML pipeline doesn't feel great when done through the API.
More specifically, the configuration field in the payload is very clunky and difficult to interface with as a human.
(I know the intention is for it to be done programmatically as an API, but it felt worth calling out)
Another nit-picky thing I've noticed is that certain values that go into a build's meta_data are casted in the response/event notification payloads. (int -> string)

What problems is the product solving and how is that benefiting you?

Being a vendored and managed service, Buildkite alleviates the pains of CI platform maintenance, helping us spend more time on things that matter more.