There are advantages to embedding. You can retain the host language type system and and object model. If you have a great query language and model but have to w

There are advantages to embedding. You can retain the host language type system and and object model. If you have a great query language and model but have to write a ton of code to marshal back and forth, it might not be adding that much value (classic impedance mismatch). While go’s compile time metaprogamming is virtually non-existent, it’s runtime metaprogramming with reflection is more or less complete. There’s a runtime cost to using it, but that can be mitigated. See https://github.com/cockroachdb/cockroach/tree/master/pkg/sql/schemachanger/rel https://github.com/cockroachdb/cockroach/tree/master/pkg/sql... for a reflection-driven, embedded logic query language in go that achieves pragmatic goals of writing logic queries over data structure graphs at reasonable performance and pretty good expressibility.