diff --git a/gnu/packages/toolkits.scm b/gnu/packages/toolkits.scm
index d68603f0cb2..943e01d1b07 100644
--- a/gnu/packages/toolkits.scm
+++ b/gnu/packages/toolkits.scm
@@ -23,12 +23,14 @@
   #:use-module (gnu packages documentation)
   #:use-module (gnu packages fontutils)
   #:use-module (gnu packages gl)
+  #:use-module (gnu packages python-build)
   #:use-module (gnu packages sdl)
   #:use-module (guix gexp)
   #:use-module ((guix licenses) #:prefix license:)
   #:use-module (guix packages)
   #:use-module (guix utils)
   #:use-module (guix build-system gnu)
+  #:use-module (guix build-system pyproject)
   #:use-module (guix build-system python)
   #:use-module (guix git-download))
 
@@ -190,46 +192,49 @@ standard operating system features.")
     (name "nuklear")
     (version "4.12.0")
     (home-page "https://github.com/Immediate-Mode-UI/Nuklear")
-    (source (origin
-              (method git-fetch)
-              (uri (git-reference
-                    (url home-page)
-                    (commit version)))
-              (file-name (git-file-name name version))
-              (sha256
-               (base32
-                "13cswwdys4hqdvbm4g4b9l269i16s7c4204j16v67ghj3b4mjifg"))
-              (snippet #~(begin (delete-file "nuklear.h")
-                                (delete-file "doc/index.html")))))
-    (build-system python-build-system)
+    (source
+     (origin
+       (method git-fetch)
+       (uri (git-reference
+             (url home-page)
+             (commit version)))
+       (file-name (git-file-name name version))
+       (sha256
+        (base32 "13cswwdys4hqdvbm4g4b9l269i16s7c4204j16v67ghj3b4mjifg"))
+       (snippet #~(begin
+                    (delete-file "nuklear.h")
+                    (delete-file "doc/index.html")))))
+    (build-system pyproject-build-system)
     (arguments
-     (list #:tests? #f ;no tests
-           #:phases #~(modify-phases %standard-phases
-                        (delete 'configure)
-                        (replace 'build
-                          (lambda _
-                            (with-directory-excursion "src"
-                              (invoke "./paq.sh"))
-                            (with-directory-excursion "doc"
-                              (with-input-from-file "../nuklear.h"
-                                (lambda _
-                                  (with-output-to-file "index.html"
-                                    (lambda _
-                                      (invoke "stddoc"))))))))
-                        (replace 'install
-                          (lambda* (#:key outputs #:allow-other-keys)
-                            (install-file "nuklear.h"
-                                          (string-append #$output "/include"))
-                            (install-file "doc/index.html"
-                                          (string-append #$output
-                                                         "/share/doc")))))))
-    (native-inputs (list stddoc))
+     (list
+      #:tests? #f ;no tests
+      #:phases
+      #~(modify-phases %standard-phases
+          (delete 'configure)
+          (replace 'build
+            (lambda _
+              (with-directory-excursion "src"
+                (invoke "./paq.sh"))
+              (with-directory-excursion "doc"
+                (with-input-from-file "../nuklear.h"
+                  (lambda _
+                    (with-output-to-file "index.html"
+                      (lambda _
+                        (invoke "stddoc"))))))))
+          (replace 'install
+            (lambda _
+              (install-file "nuklear.h"
+                            (string-append #$output "/include"))
+              (install-file "doc/index.html"
+                            (string-append #$output "/share/doc")))))))
+    (native-inputs (list stddoc python-setuptools))
     (synopsis "Graphical user interface toolkit written in ANSI C")
-    (description "This package provides an immediate-mode graphical user
-interface toolkit.  It was designed as an embeddable user interface
-for applications and does not have any dependencies, a default render backend
-or OS window/input handling.  The library is self contained in one single header
-file and can be used either in header only mode or in implementation mode.")
+    (description
+     "This package provides an immediate-mode graphical user interface
+toolkit.  It was designed as an embeddable user interface for applications and
+does not have any dependencies, a default render backend or OS window/input
+handling.  The library is self contained in one single header file and can be
+used either in header only mode or in implementation mode.")
     (license (list license:unlicense license:expat))))
 
 (define-public implot