I have this file which i use to interact with a version controlled 
repository similar to a Makefile.

How can i make it work with e.g. `./file.scm echo wheee` -> Will execute 
the `(define (echo msg) ...)` and output `wheee` in the terminal?

FWIW preferably i want it to work like `./file.scm echo whee build` so 
that it would output `wheee` and then ran the `(define (build) ...)` 
task too..

#!/usr/bin/env sh
exec guile -s "$0" "$@"
!#
;;; This file is used to interact with the project

;;; ==== [START] TO BE INCLUDED IN A LIBRARY [START] ==== ;;;

;; Get path to the current filename
(define-public %repo-root (dirname (current-filename)))

;;; ==== [STOP] TO BE INCLUDED IN A LIBRARY [STOP] ==== ;;;

;; FIXME-QA(Krey): We need to define an alternative to `(define 
(task)...)` to be more workable and faster to write

;;; Tasks
;; DESIGN(Krey): Build the system configuration
(define (build)
   (system* "guix"
        "system"
        "build"
        (string-append %repo-root "/config.scm")))

;; DESIGN(Krey): Deploy the system configuration on the current system
(define (deploy)
   (system* "guix"
        "system"
        "reconfigure"
        (string-append %repo-root "/config.scm")))

;; DESIGN(Krey): Build the bare minimal image for rockpro64
(define (tools-minimal-rockpro64)
   (system* "guix"
        "system"
        "--system=aarch64-linux"
        "image"
        (string-append %file-root "/config.scm")))

;; Processing of cli arguments
(define (echo msg) (system* "echo" msg))

;; DESIGN(Krey): Expecting to process the command-line args here
;; HOTFIX(Krey): Didn't figure out how to do it yet, so currently 
hard-coding
; deploy

;(quote (cdr (command-line)))
;;(match (command-line) ((_ "build") (build)))