\setvariables and \getvariables sounds like the most general solution

in that case.

For example, you could put the various \setvariables statements in various separate files and load a specific one from the context command line with --environment=...

 

I tried it and it works. Only one thing: when the variables are not set (forgot the environment parameter, file not correctly set, ...) I would like to set default values. How would I do that?

%\enablemode[variables]

\startmode[variables]

\setvariables

  [test]

  [one=One,

   two=Two]

\stopmode

\starttext

\doifelsevariable{test}{one}{1: \getvariable{test}{one}}{??}\par

\doifelsevariable{test}{two}{2: \getvariable{test}{two}}{??}

\stoptext