Newbie Packaging Question

[Brian Woodcox]

I have a question regarding packaging.

Say I have the following in my sample.scm file:

(define commit "a1ee2ebf087768b5fbffa07f50a294ad9c8ee600")

(define version-date “201903271913”)

and then

(define-public test-me
  (package
  (name “test-me”)
  (version commit)
  (source …
               .
               .
               . etc...


In my modify-phases %standard-phases,  I am trying to use substitute* to patch 
some files with the version-date define outside my package.

Is this not possible, I always get an unbound variable error.

I have no problem accessing the commit variable which is defined outside of the 
package.

Any help would be greatly appreciated.

Thanks.