It looks like I had declared some package dependencies 
incorrectly. They fact that they worked after I installed them was 
sheer luck. This patch should correct the dependency chain and 
update the PATH correctly.

* gnu/packages/ruby.scm (ruby-theme-check): Correct dependencies
(ruby-shopify-cli): Correct dependencies

---
 gnu/packages/ruby.scm | 8 ++------
 1 file changed, 2 insertions(+), 6 deletions(-)

diff --git a/gnu/packages/ruby.scm b/gnu/packages/ruby.scm
index 1637be8c1b..190322c644 100644
--- a/gnu/packages/ruby.scm
+++ b/gnu/packages/ruby.scm
@@ -11229,9 +11229,6 @@ (define-public ruby-theme-check
                "00sqbnbz6bspdzgmcdiziql1lvf0gzxk74hlvwcqsdka78bg0nk0"))))
    (build-system ruby-build-system)
    (arguments '(#:tests? #f))
-   (inputs `(("ruby-liquid" ,ruby-liquid)
-             ("ruby-nokogiri" ,ruby-nokogiri)
-             ("ruby-parser" ,ruby-parser)))
    (propagated-inputs (list ruby-liquid ruby-nokogiri 
    ruby-parser))
    (synopsis "A Shopify Theme Linter")
    (description "This package provides a Shopify Theme Linter")
@@ -11249,9 +11246,8 @@ (define-public ruby-shopify-cli
                (base32
                 "1fcqc8bpai3pnp77v4im2l92p40jnqikch8s5336lc4gp498vfb5"))))
     (build-system ruby-build-system)
-    (inputs `(("ruby-bugsnag" ,ruby-bugsnag)
-              ("ruby-listen"  ,ruby-listen)
-              ("ruby-theme-check" ,ruby-theme-check)))
+    (inputs (list ruby-bugsnag ruby-listen))
+    (propagated-inputs (list ruby-theme-check))
     (arguments '(#:tests? #f))
     (synopsis "Shopify CLI helps you build Shopify themes and 
     apps")
     (description "Use Shopify CLI to automate and enhance your 
     local
-- 
2.36.1