they use different approaches. 23andme even has a short writeup on this: https://customercare.23andme.com/hc/en-us/articles/202904600...

Its really just a layer on top that uses the groovy DSL features

http://docs.groovy-lang.org/docs/latest/html/documentation/c...

nextflow can't even get this right- base nextflow uses some combination of `--paramName` and `--param-name` and treats them as interchangeable, while nf-core encourages `--param_name` (but nextflow sees that as different). All trivial differences but just layers on the CLI frustration train.