diff --git a/gnu/packages/admin.scm b/gnu/packages/admin.scm
index c9dd154313..e508340ef0 100644
--- a/gnu/packages/admin.scm
+++ b/gnu/packages/admin.scm
@@ -6237,21 +6237,22 @@ (define (make-suite str)
                 (((make-suite "servertestcase.ServerConfigReaderTests"))
                  ""))))
           (add-before 'build 'fix-default-config
-            (lambda* (#:key outputs #:allow-other-keys)
+            (lambda _
               (substitute* '("config/paths-common.conf"
                              "fail2ban/tests/utils.py"
                              "fail2ban/client/configreader.py"
                              "fail2ban/client/fail2bancmdline.py"
                              "fail2ban/client/fail2banregex.py")
                 (("/etc/fail2ban")
-                 (string-append (assoc-ref outputs "out") "/etc/fail2ban")))))
+                 (string-append #$output "/etc/fail2ban")))))
           (add-after 'fix-default-config 'set-action-dependencies
             (lambda* (#:key inputs #:allow-other-keys)
               ;; deleting things that are not feasible to fix
               ;; or won't be used any way
               (with-directory-excursion "config/action.d"
                 (for-each delete-file
-                          '("apf.conf" "bsd-ipfw.conf"
+                          '("apf.conf"
+                            "bsd-ipfw.conf"
                             "dshield.conf"
                             "ipfilter.conf"
                             "ipfw.conf"
@@ -6270,74 +6271,60 @@ (define (make-suite str)
                             "shorewall.conf"
                             "shorewall-ipset-proto6.conf"
                             "ufw.conf")))
-              (let* ((lookup-cmd (lambda (i)
-                                   (search-input-file inputs i)))
-                     (bin (lambda (i)
-                            (lookup-cmd (string-append "/bin/" i))))
-                     (sbin (lambda (i)
-                             (lookup-cmd (string-append "/sbin/" i))))
-                     (ip (sbin "ip"))
-                     (sendmail (sbin "sendmail")))
-                (substitute* (find-files "config/action.d" "\\.conf$")
-                  ;; TODO: deal with geoiplookup ..
-                  (("(awk|curl|dig|jq)" all cmd)
-                   (bin cmd))
-                  (("(cat|echo|grep|head|printf|wc) " all cmd)
-                   (string-append (bin cmd) " "))
-                  ((" (date|rm|sed|tail|touch|tr) " all cmd)
-                   (string-append " "
-                                  (bin cmd) " "))
-                  (("cut -d")
-                   (string-append (bin "cut") " -d"))
-                  (("`date`")
-                   (string-append "`"
-                                  (bin "date") "`"))
-                  (("id -")
-                   (string-append (bin "id") " -"))
-                  (("ip -([46]) addr" all ver)
-                   (string-append ip " -" ver " addr"))
-                  (("ip route")
-                   (string-append ip " route"))
-                  (("ipset ")
-                   (string-append (sbin "ipset") " "))
-                  (("(iptables|ip6tables) <" all cmd)
-                   (string-append (sbin cmd) " <"))
-                  (("/usr/bin/nsupdate")
-                   (bin "nsupdate"))
-                  (("mail -E")
-                   (string-append sendmail " -E"))
-                  (("nftables = nft")
-                   (string-append "nftables = "
-                                  (sbin "nft")))
-                  (("perl -e")
-                   (string-append (bin "perl") " -e"))
-                  (("/usr/sbin/sendmail")
-                   sendmail)
-                  (("test -e")
-                   (string-append (bin "test") " -e"))
-                  (("_whois = whois")
-                   (string-append "_whois = "
-                                  (bin "whois")))))
+              (define (lookup dir file)
+                (search-input-file inputs (string-append "/" dir "/" file)))
+
+              (substitute* (find-files "config/action.d" "\\.conf$")
+                ;; TODO: deal with geoiplookup ..
+                (("(awk|curl|dig|jq)" all cmd)
+                 (lookup "bin" cmd))
+                (("(cat|echo|grep|head|printf|wc) " all cmd)
+                 (string-append (lookup "bin" cmd) " "))
+                ((" (date|rm|sed|tail|touch|tr) " all cmd)
+                 (string-append " " (lookup "bin" cmd) " "))
+                (("cut -d")
+                 (string-append (lookup "bin" "cut") " -d"))
+                (("`date`")
+                 (string-append "`" (lookup "bin" "date") "`"))
+                (("id -")
+                 (string-append (lookup "bin" "id") " -"))
+                (("ip (route|-[46] addr)" all rest)
+                 (string-append (lookup "sbin" "ip") rest))
+                (("ipset ")
+                 (string-append (lookup "sbin" "ipset") " "))
+                (("(iptables|ip6tables) <" all cmd)
+                 (string-append (lookup "sbin" cmd) " <"))
+                (("/usr/bin/nsupdate")
+                 (lookup "bin" "nsupdate"))
+                (("mail -E")
+                 (string-append (lookup "sbin" "sendmail") " -E"))
+                (("nftables = nft")
+                 (string-append "nftables = " (lookup "sbin" "nft")))
+                (("perl -e")
+                 (string-append (lookup "bin" "perl") " -e"))
+                (("/usr/sbin/sendmail")
+                 (lookup "sbin" "sendmail"))
+                (("test -e")
+                 (string-append (lookup "bin" "test") " -e"))
+                (("_whois = whois")
+                 (string-append "_whois = " (lookup "bin" "whois"))))
+
               (substitute* "config/jail.conf"
                 (("before = paths-debian\\.conf")
                  "before = paths-guix.conf"))))
           (add-after 'install 'copy-man-pages
-            (lambda* (#:key outputs #:allow-other-keys)
-              (let* ((man (string-append (assoc-ref outputs "out") "/man"))
-                     (install-man (lambda (m)
-                                    (lambda (f)
-                                      (install-file (string-append f "." m)
-                                                    (string-append man "/man"
-                                                                   m)))))
-                     (install-man1 (install-man "1"))
-                     (install-man5 (install-man "5")))
-                (with-directory-excursion "man"
-                  (for-each install-man1
-                            '("fail2ban" "fail2ban-client" "fail2ban-python"
-                              "fail2ban-regex" "fail2ban-server"
-                              "fail2ban-testcases"))
-                  (for-each install-man5
-                            '("jail.conf")))))))))
+            (lambda _
+              (define (install-man m)
+                (lambda (f)
+                  (install-file (string-append f "." m)
+                                (string-append #$output "man/man" m))))
+
+              (with-directory-excursion "man"
+                (for-each (install-man "1")
+                          '("fail2ban" "fail2ban-client" "fail2ban-python"
+                            "fail2ban-regex" "fail2ban-server"
+                            "fail2ban-testcases"))
+                ((install-man "5") "jail.conf")))))))
     (native-inputs (list python-setuptools python-wheel))
     (inputs (list gawk
                   coreutils-minimal
