Builds - Specifying a data source for builds

Thanks @nathanmartin - I did run across this option and managed to get a proof-of-concept working.

There were a few pitfalls I found with using the webhook build payload (although I may be missing something), mainly that internal source plugin changes were necessary to get it up and running. This is fine for us as we maintain multiple private source plugins, but others might run into trouble if they’re using third-party plugins.

Realistically what I was aiming to achieve was something close to Gatsby Cloud’s Cloud/Data Update Builds, but this post makes it clear that this probably isn’t achievable.

Although incremental builds are working in some fashion, equivalent builds have gone from 10-20 seconds in Gatsby Cloud to ~2 minutes on Netlify which is more than a little disheartening.