diff --git a/gnu/packages/java.scm b/gnu/packages/java.scm
index 5d36574..2f6d297 100644
--- a/gnu/packages/java.scm
+++ b/gnu/packages/java.scm
@@ -143,10 +143,18 @@ is implemented.")
               license:lgpl2.1+))))
 
 (define-public clojure
-  (let ((remove-archives '(begin
-                            (for-each delete-file
-                                      (find-files "./" ".*\\.(jar|zip)"))
-                            #t)))
+  (let* ((remove-archives '(begin
+                             (for-each delete-file
+                                       (find-files "." ".*\\.(jar|zip)"))
+                             #t))
+         (submodule (lambda (prefix version hash)
+                      (origin
+                        (method url-fetch)
+                        (uri (string-append "https://github.com/clojure/"
+                                            prefix version ".tar.gz"))
+                        (sha256 (base32 hash))
+                        (modules '((guix build utils)))
+                        (snippet remove-archives)))))
     (package
       (name "clojure")
       (version "1.8.0")
@@ -164,8 +172,6 @@ is implemented.")
       (arguments
        `(#:modules ((guix build ant-build-system)
                     (guix build utils)
-                    (ice-9 ftw)
-                    (ice-9 regex)
                     (srfi srfi-1)
                     (srfi srfi-26))
          #:test-target "test"
@@ -173,134 +179,78 @@ is implemented.")
          (modify-phases %standard-phases
            (add-after 'unpack 'unpack-submodule-sources
              (lambda* (#:key inputs #:allow-other-keys)
-               (let ((unpack
-                      (lambda (src-name)
-                        (and (mkdir-p src-name)
-                             (with-directory-excursion src-name
-                               (zero? (system* "tar"
-                                               ;; Use xz for repacked tarball.
-                                               "--xz"
-                                               "--extract"
-                                               "--verbose"
-                                               "--file" (assoc-ref inputs
-                                                                   src-name)
-                                               "--strip-components=1"))))))
-                     (copy (lambda (src-name)
-                             (copy-recursively
-                              (string-append src-name "/src/main/clojure/")
-                              "src/clj/"))))
-                 (every (lambda (src)
-                          (unpack src)
-                          (copy src))
-                        '("data-generators-src" "java-classpath-src"
-                          "test-check-src" "test-generative-src"
-                          "tools-namespace-src" "tools-reader-src")))))
-           ;;; The javadoc target is not built by default.
+               (for-each
+                (lambda (name)
+                  (mkdir-p name)
+                  (with-directory-excursion name
+                    (or (zero? (system* "tar"
+                                        ;; Use xz for repacked tarball.
+                                        "--xz"
+                                        "--extract"
+                                        "--verbose"
+                                        "--file" (assoc-ref inputs name)
+                                        "--strip-components=1"))
+                        (error "failed to unpack tarball" name)))
+                  (copy-recursively (string-append name "/src/main/clojure/")
+                                    "src/clj/"))
+                '("data-generators-src"
+                  "java-classpath-src"
+                  "test-check-src"
+                  "test-generative-src"
+                  "tools-namespace-src"
+                  "tools-reader-src"))
+               #t))
+           ;; The javadoc target is not built by default.
            (add-after 'build 'build-doc
              (lambda _
                (zero? (system* "ant" "javadoc"))))
-           ;;; Needed since no install target is provided.
+           ;; Needed since no install target is provided.
            (replace 'install
              (lambda* (#:key outputs #:allow-other-keys)
                (let ((java-dir (string-append (assoc-ref outputs "out")
                                               "/share/java/")))
-                 ;; Do not install clojure.jar to avoid collisions.
+                 ;; Install versioned to avoid collisions.
                  (install-file (string-append "clojure-" ,version ".jar")
                                java-dir)
                  #t)))
-           ;;; Needed since no install-doc target is provided.
+           ;; Needed since no install-doc target is provided.
            (add-after 'install 'install-doc
              (lambda* (#:key outputs #:allow-other-keys)
                (let ((doc-dir (string-append (assoc-ref outputs "out")
                                              "/share/doc/clojure-"
                                              ,version "/")))
-                 (and (copy-recursively "doc/clojure" doc-dir)
-                      (copy-recursively "target/javadoc/"
-                                        (string-append doc-dir "javadoc/")))
+                 (copy-recursively "doc/clojure" doc-dir)
+                 (copy-recursively "target/javadoc/"
+                                   (string-append doc-dir "javadoc/"))
                  (for-each (cut install-file <> doc-dir)
-                           (filter (cut string-match
-                                     ".*\\.(html|markdown|md|txt)"
-                                     <>)
-                                   (scandir "./")))
+                           (find-files "." ".*\\.(html|markdown|md|txt)"))
                  #t))))))
       ;; The native-inputs below are needed to run the tests.
       (native-inputs
        `(("data-generators-src"
-          ,(let ((version "0.1.2"))
-             (origin
-               (method url-fetch)
-               (uri (string-append "https://github.com/clojure"
-                                   "/data.generators/archive/data.generators-"
-                                   version ".tar.gz"))
-               (sha256
-                (base32
-                 "0kki093jp4ckwxzfnw8ylflrfqs8b1i1wi9iapmwcsy328dmgzp1"))
-               (modules '((guix build utils)
-                          (ice-9 ftw)))
-               (snippet remove-archives))))
+          ,(submodule "data.generators/archive/data.generators-"
+                      "0.1.2"
+                      "0kki093jp4ckwxzfnw8ylflrfqs8b1i1wi9iapmwcsy328dmgzp1"))
          ("java-classpath-src"
-          ,(let ((version "0.2.3"))
-             (origin
-               (method url-fetch)
-               (uri
-                (string-append "https://github.com/clojure"
-                               "/java.classpath/archive/java.classpath-"
-                               version ".tar.gz"))
-               (sha256
-                (base32
-                 "0sjymly9xh1lkvwn5ygygpsfwz4dabblnlq0c9bx76rkvq62fyng"))
-               (modules '((guix build utils)))
-               (snippet remove-archives))))
+          ,(submodule "java.classpath/archive/java.classpath-"
+                      "0.2.3"
+                      "0sjymly9xh1lkvwn5ygygpsfwz4dabblnlq0c9bx76rkvq62fyng"))
          ("test-check-src"
-          ,(let ((version "0.9.0"))
-             (origin
-               (method url-fetch)
-               (uri
-                (string-append "https://github.com/clojure"
-                               "/test.check/archive/test.check-"
-                               version ".tar.gz"))
-               (sha256
-                (base32
-                 "0p0mnyhr442bzkz0s4k5ra3i6l5lc7kp6ajaqkkyh4c2k5yck1md"))
-               (modules '((guix build utils)))
-               (snippet remove-archives))))
+          ,(submodule "test.check/archive/test.check-"
+                      "0.9.0"
+                      "0p0mnyhr442bzkz0s4k5ra3i6l5lc7kp6ajaqkkyh4c2k5yck1md"))
          ("test-generative-src"
-          ,(let ((version "0.5.2"))
-             (origin
-               (method url-fetch)
-               (uri (string-append "https://github.com/clojure"
-                                   "/test.generative/archive/test.generative-"
-                                   version ".tar.gz"))
-               (sha256
-                (base32
-                 "1pjafy1i7yblc7ixmcpfq1lfbyf3jaljvkgrajn70sws9xs7a9f8"))
-               (modules '((guix build utils)))
-               (snippet remove-archives))))
+          ,(submodule "test.generative/archive/test.generative-"
+                      "0.5.2"
+                      "1pjafy1i7yblc7ixmcpfq1lfbyf3jaljvkgrajn70sws9xs7a9f8"))
          ("tools-namespace-src"
-          ,(let ((version "0.2.11"))
-             (origin
-               (method url-fetch)
-               (uri (string-append "https://github.com/clojure"
-                                   "/tools.namespace/archive/tools.namespace-"
-                                   version ".tar.gz"))
-               (sha256
-                (base32
-                 "10baak8v0hnwz2hr33bavshm7y49mmn9zsyyms1dwjz45p5ymhy0"))
-               (modules '((guix build utils)))
-               (snippet remove-archives))))
+          ,(submodule "tools.namespace/archive/tools.namespace-"
+                      "0.2.11"
+                      "10baak8v0hnwz2hr33bavshm7y49mmn9zsyyms1dwjz45p5ymhy0"))
          ("tools-reader-src"
-          ,(let ((version "0.10.0"))
-             (origin
-               (method url-fetch)
-               (uri
-                (string-append "https://github.com/clojure"
-                               "/tools.reader/archive/tools.reader-"
-                               version ".tar.gz"))
-               (sha256
-                (base32
-                 "09i3lzbhr608h76mhdjm3932gg9xi8sflscla3c5f0v1nkc28cnr"))
-               (modules '((guix build utils)))
-               (snippet remove-archives))))))
+          ,(submodule "tools.reader/archive/tools.reader-"
+                      "0.10.0"
+                      "09i3lzbhr608h76mhdjm3932gg9xi8sflscla3c5f0v1nkc28cnr"))))
       (home-page "https://clojure.org/")
       (synopsis "Lisp dialect running on the JVM")
       (description "Clojure is a dynamic, general-purpose programming language,