Welcome to the CHICKEN Scheme pasting service

;; In Chicken 4 this code returns: hallo-test (what I want ;)
;; In Chicken 5 this code returns: hallo2829-test, it seems like (inj <a>) returns an uninterned symbol.

(define-syntax ir-test
  (ir-macro-transformer
   (lambda (exp inj _)
     (apply (lambda (_ <a>)
              `(print ',(symbol-append (inj <a>) '-test)))
            exp))))

(ir-test hallo)