Inject multiple node dependencies within one template, each with dedicated skip_if's about hygen HOT 1 OPEN

That would require especial parsing and allowing frontmatter in the middle may be complicated.

How about adding a modify or update action that gets the existing file content and returns the updated content?

That could be achieved in at least two ways, by having a variable contents in the context and a normal ejs body, or by having the template export a function transform(contents: string, context: {}): string as a named or as the default export

from hygen.