diff --git a/gnu/local.mk b/gnu/local.mk
index cf8849cf59..51dcf4e6e6 100644
--- a/gnu/local.mk
+++ b/gnu/local.mk
@@ -40,6 +40,7 @@
 # Copyright © 2020 Malte Frank Gerdes <mate.f.gerdes@gmail.com>
 # Copyright © 2020 Vinicius Monego <monego@posteo.net>
 # Copyright © 2021 Björn Höfling <bjoern.hoefling@bjoernhoefling.de>
+# Copyright © 2021 Philip McGrath <philip@philipmcgrath.com>
 #
 # This file is part of GNU Guix.
 #
@@ -1629,6 +1630,7 @@ dist_patch_DATA =						\
   %D%/packages/patches/ripperx-missing-file.patch		\
   %D%/packages/patches/rpcbind-CVE-2017-8779.patch		\
   %D%/packages/patches/rtags-separate-rct.patch			\
+  %D%/packages/patches/racket-sh-via-rktio.patch		\
   %D%/packages/patches/racket-store-checksum-override.patch	\
   %D%/packages/patches/remake-impure-dirs.patch			\
   %D%/packages/patches/retroarch-LIBRETRO_DIRECTORY.patch	\
diff --git a/gnu/packages/patches/racket-sh-via-rktio.patch b/gnu/packages/patches/racket-sh-via-rktio.patch
new file mode 100644
index 0000000000..870e8eb5f2
--- /dev/null
+++ b/gnu/packages/patches/racket-sh-via-rktio.patch
@@ -0,0 +1,91 @@
+From 34fd01842d5211e73260721b7a516487e982497c Mon Sep 17 00:00:00 2001
+From: Philip McGrath <philip@philipmcgrath.com>
+Date: Thu, 4 Mar 2021 04:11:50 -0500
+Subject: [PATCH] patch rktio_process for "/bin/sh" on Guix
+
+Racket provides the functions `system` and `process`,
+which execute shell commands using `sh` (or `cmd` on Windows).
+Racket assumes that `sh` can be found at "/bin/sh",
+which is not necessarily true on Guix.
+
+This patch adds a special case for "/bin/sh" to `rktio_process`,
+the C function that implements the core of `system`, `process`,
+and related Racket functions.
+
+Guix should enable the special case by defining the C preprocessor
+macro `GUIX_RKTIO_PATCH_BIN_SH` with the path to `sh` in the store.
+If:
+
+    1. The `GUIX_RKTIO_PATCH_BIN_SH` macro is defined; and
+
+    2. `rktio_process` is called with the exact path "/bin/sh"; and
+
+    3. "/bin/sh" does not exist (if it does, we don't want to change
+       the expected behavior); and
+
+    4. The path specified by `GUIX_RKTIO_PATCH_BIN_SH` does exists;
+
+then `rktio_process` will execute the file specified
+by `GUIX_RKTIO_PATCH_BIN_SH` instead of "/bin/sh".
+
+Compared to previous attempts to patch the Racket sources,
+making this change at the C level is both:
+
+    - More comprehensive: it catches all attempts to execute "/bin/sh",
+      without having to track down the source of every occurance; and
+
+    - Less intrusive: by guarding the special case with a C preprocessor
+      conditional and a runtime check that the file in the store exists,
+      we make it much less likely that it will "leak" out of Guix.
+---
+ src/rktio/rktio_process.c | 22 +++++++++++++++++++++-
+ 1 file changed, 21 insertions(+), 1 deletion(-)
+
+diff --git a/src/rktio/rktio_process.c b/src/rktio/rktio_process.c
+index 89202436c0..ff65a434e2 100644
+--- a/src/rktio/rktio_process.c
++++ b/src/rktio/rktio_process.c
+@@ -1224,12 +1224,14 @@ int rktio_process_allowed_flags(rktio_t *rktio)
+ /*========================================================================*/
+ 
+ rktio_process_result_t *rktio_process(rktio_t *rktio,
+-                                      const char *command, int argc, rktio_const_string_t *argv,
++                                      /* PATCHED for Guix (next line) */
++                                      const char *_guix_orig_command, int argc, rktio_const_string_t *argv,
+                                       rktio_fd_t *stdout_fd, rktio_fd_t *stdin_fd, rktio_fd_t *stderr_fd,
+                                       rktio_process_t *group_proc,
+                                       const char *current_directory, rktio_envvars_t *envvars,
+                                       int flags)
+ {
++  const char *command; /* PATCHED for Guix */
+   rktio_process_result_t *result;
+   intptr_t to_subprocess[2], from_subprocess[2], err_subprocess[2];
+   int pid;
+@@ -1255,6 +1257,24 @@ rktio_process_result_t *rktio_process(rktio_t *rktio,
+   int i;
+ #endif
+ 
++/* BEGIN PATCH for Guix */
++#if defined(GUIX_RKTIO_PATCH_BIN_SH)
++# define GUIX_AS_a_STR_HELPER(x) #x
++# define GUIX_AS_a_STR(x) GUIX_AS_a_STR_HELPER(x)
++  /* A level of indirection makes `#` work as needed: */
++  command =
++      ((0 == strcmp(_guix_orig_command, "/bin/sh"))
++       && (! rktio_file_exists(rktio, "/bin/sh"))
++       && rktio_file_exists(rktio, GUIX_AS_a_STR(GUIX_RKTIO_PATCH_BIN_SH)))
++      ? GUIX_AS_a_STR(GUIX_RKTIO_PATCH_BIN_SH)
++      : _guix_orig_command;
++# undef GUIX_AS_a_STR
++# undef GUIX_AS_a_STR_HELPER
++#else
++  command = _guix_orig_command;
++#endif
++/* END PATCH for Guix */
++
+   /* avoid compiler warnings: */
+   to_subprocess[0] = -1;
+   to_subprocess[1] = -1;
+-- 
+2.25.1
+
diff --git a/gnu/packages/scheme.scm b/gnu/packages/scheme.scm
index 10be0aa28a..8656fef1ab 100644
--- a/gnu/packages/scheme.scm
+++ b/gnu/packages/scheme.scm
@@ -43,6 +43,7 @@
   #:use-module (guix build-system trivial)
   #:use-module (gnu packages autotools)
   #:use-module (gnu packages bdw-gc)
+  #:use-module (gnu packages bash)
   #:use-module (gnu packages compression)
   #:use-module (gnu packages databases)
   #:use-module (gnu packages libevent)
@@ -411,94 +412,26 @@ implementation techniques and as an expository tool.")
                (base32
                 "047wpjblfzmf1msz7snrp2c2h0zxyzlmbsqr9bwsyvz3frcg0888"))
               (patches (search-patches
+                        "racket-sh-via-rktio.patch"
+                        ;; TODO: If we're no longer patching Racket source
+                        ;; files with store paths, we may also fix the
+                        ;; issue that necessitated the following patch:
                         "racket-store-checksum-override.patch"))))
     (build-system gnu-build-system)
     (arguments
-     '(#:configure-flags
-       '("--enable-libz"
+     `(#:configure-flags
+       `(,(string-append "CPPFLAGS=-DGUIX_RKTIO_PATCH_BIN_SH="
+                         (assoc-ref %build-inputs "sh")
+                         "/bin/sh")
+         "--enable-libz"
          "--enable-liblz4")
+       #:modules
+       ((guix build gnu-build-system)
+        (guix build utils)
+        (srfi srfi-1))
        #:phases
        (modify-phases %standard-phases
-         (add-before 'configure 'pre-configure-minimal
-           (lambda* (#:key inputs #:allow-other-keys)
-             ;; Patch dynamically loaded libraries with their absolute paths.
-             (let* ((library-path (search-path-as-string->list
-                                   (getenv "LIBRARY_PATH")))
-                    (find-so (lambda (soname)
-                               (search-path
-                                library-path
-                                (format #f "~a.so" soname)))))
-               (substitute* "collects/db/private/sqlite3/ffi.rkt"
-                 (("ffi-lib sqlite-so")
-                  (format #f "ffi-lib \"~a\"" (find-so "libsqlite3"))))
-               (substitute* "collects/openssl/libssl.rkt"
-                 (("ffi-lib libssl-so")
-                  (format #f "ffi-lib \"~a\"" (find-so "libssl"))))
-               (substitute* "collects/openssl/libcrypto.rkt"
-                 (("ffi-lib libcrypto-so")
-                  (format #f "ffi-lib \"~a\"" (find-so "libcrypto")))))
-             (chdir "src")
-             #t))
-         (add-before 'pre-configure-minimal 'pre-configure
-           (lambda* (#:key inputs #:allow-other-keys)
-             ;; Patch dynamically loaded libraries with their absolute paths.
-             (let* ((library-path (search-path-as-string->list
-                                   (getenv "LIBRARY_PATH")))
-                    (find-so (lambda (soname)
-                               (search-path
-                                library-path
-                                (format #f "~a.so" soname))))
-                    (patch-ffi-libs (lambda (file libs)
-                                      (for-each
-                                       (lambda (lib)
-                                         (substitute* file
-                                           (((format #f "\"~a\"" lib))
-                                            (format #f "\"~a\"" (find-so lib)))))
-                                       libs))))
-               (substitute* "share/pkgs/math-lib/math/private/bigfloat/gmp.rkt"
-                 (("ffi-lib libgmp-so")
-                  (format #f "ffi-lib \"~a\"" (find-so "libgmp"))))
-               (substitute* "share/pkgs/math-lib/math/private/bigfloat/mpfr.rkt"
-                 (("ffi-lib libmpfr-so")
-                  (format #f "ffi-lib \"~a\"" (find-so "libmpfr"))))
-               (substitute* "share/pkgs/readline-lib/readline/rktrl.rkt"
-                 (("\\(getenv \"PLT_READLINE_LIB\"\\)")
-                  (format #f "\"~a\"" (find-so "libedit"))))
-               (for-each
-                (lambda (x) (apply patch-ffi-libs x))
-                '(("share/pkgs/draw-lib/racket/draw/unsafe/cairo-lib.rkt"
-                   ("libfontconfig" "libcairo"))
-                  ("share/pkgs/draw-lib/racket/draw/unsafe/glib.rkt"
-                   ("libglib-2.0" "libgmodule-2.0" "libgobject-2.0"))
-                  ("share/pkgs/draw-lib/racket/draw/unsafe/jpeg.rkt"
-                   ("libjpeg"))
-                  ("share/pkgs/draw-lib/racket/draw/unsafe/pango.rkt"
-                   ("libpango-1.0" "libpangocairo-1.0"))
-                  ("share/pkgs/draw-lib/racket/draw/unsafe/png.rkt"
-                   ("libpng"))
-                  ("share/pkgs/db-lib/db/private/odbc/ffi.rkt"
-                   ("libodbc"))
-                  ("share/pkgs/gui-lib/mred/private/wx/gtk/x11.rkt"
-                   ("libX11"))
-                  ("share/pkgs/gui-lib/mred/private/wx/gtk/gsettings.rkt"
-                   ("libgio-2.0"))
-                  ("share/pkgs/gui-lib/mred/private/wx/gtk/gtk3.rkt"
-                   ("libgdk-3" "libgtk-3"))
-                  ("share/pkgs/gui-lib/mred/private/wx/gtk/unique.rkt"
-                   ("libunique-1.0"))
-                  ("share/pkgs/gui-lib/mred/private/wx/gtk/utils.rkt"
-                   ("libgdk-x11-2.0" "libgdk_pixbuf-2.0" "libgtk-x11-2.0"))
-                  ("share/pkgs/gui-lib/mred/private/wx/gtk/gl-context.rkt"
-                   ("libGL"))
-                  ("share/pkgs/sgl/gl.rkt"
-                   ("libGL" "libGLU")))))
-             #t))
-         (add-after 'unpack 'patch-/bin/sh
-           (lambda _
-             (substitute* "collects/racket/system.rkt"
-               (("/bin/sh") (which "sh")))
-             #t))
-         (add-after 'patch-/bin/sh 'patch-chez-configure
+         (add-after 'unpack 'patch-chez-configure
            (lambda* (#:key inputs outputs #:allow-other-keys)
              (substitute* "src/cs/c/Makefile.in"
                (("/bin/sh") (which "sh")))
@@ -526,12 +459,69 @@ implementation techniques and as an expository tool.")
                  (("/bin/cp") (which "cp"))
                  (("/bin/echo") (which "echo")))
                (substitute* "makefiles/installsh"
-                 (("/bin/true") (which "true")))))))
+                 (("/bin/true") (which "true"))))
+             #t))
+         (add-before 'configure 'pre-configure-minimal
+           (lambda* (#:key inputs #:allow-other-keys)
+             (chdir "src")
+             #t))
+         (add-after 'build 'patch-config.rktd-lib-search-dirs
+           (lambda* (#:key inputs outputs #:allow-other-keys)
+             ;; We do this between the `build` and `install` phases
+             ;; so that we have racket to read and write the hash table,
+             ;; but it comes before `raco setup`, when foreign libraries
+             ;; are needed to build the documentation.
+             (define out (assoc-ref outputs "out"))
+             (apply invoke
+                    "./cs/c/racketcs"
+                    "-e"
+                    ,(format #f
+                             "~s"
+                             '(let* ((args
+                                      (vector->list
+                                       (current-command-line-arguments)))
+                                     (file (car args))
+                                     (extra-lib-search-dirs (cdr args)))
+                                (write-to-file
+                                 (hash-update
+                                  (file->value file)
+                                  'lib-search-dirs
+                                  (lambda (dirs)
+                                    (append dirs extra-lib-search-dirs))
+                                  null)
+                                 #:exists 'truncate/replace
+                                 file)))
+                    "--"
+                    "../etc/config.rktd"
+                    (filter-map (lambda (lib)
+                                  (cond
+                                   ((assoc-ref inputs lib)
+                                    => (lambda (pth)
+                                         (string-append pth "/lib")))
+                                   (else
+                                    #f)))
+                                '("cairo"
+                                  "fontconfig"
+                                  "glib"
+                                  "glu"
+                                  "gmp"
+                                  "gtk+"
+                                  "libjpeg"
+                                  "libpng"
+                                  "libx11"
+                                  "mesa"
+                                  "mpfr"
+                                  "openssl"
+                                  "pango"
+                                  "sqlite"
+                                  "unixodbc"
+                                  "libedit")))
+             #t)))
        ;; XXX: how to run them?
        #:tests? #f))
     (inputs
-     `(;; Hardcode dynamically loaded libraries for better functionality.
-       ;; sqlite and libraries for `racket/draw' are needed to build the doc.
+     `(;; sqlite and libraries for `racket/draw' are needed to build the doc.
+       ("sh" ,bash-minimal)
        ("zlib" ,zlib)
        ("zlib:static" ,zlib "static")
        ("lz4" ,lz4)
@@ -571,29 +561,21 @@ of languages such as Typed Racket, R5RS and R6RS Scheme, and Datalog.")
     (inherit racket)
     (name "racket-minimal")
     (version (package-version racket))
-    (source (origin
-              (method url-fetch)
-              (uri (list (string-append "https://mirror.racket-lang.org/installers/"
-                                        version "/racket-minimal-src.tgz")
-                         ;; this mirror seems to have broken HTTPS:
-                         (string-append
-                          "http://mirror.informatik.uni-tuebingen.de/mirror/racket/"
-                          version "/racket-minimal-src.tgz")))
-              (sha256
-               (base32
-                "0mwyffw4gcci8wmzxa3j28h03h0gsz55aard8qrk3lri8r2xyg21"))
-              (patches (search-patches
-                        "racket-store-checksum-override.patch"))))
+    (source
+     (origin
+       (inherit (package-source racket))
+       (uri (list (string-append "https://mirror.racket-lang.org/installers/"
+                                 version "/racket-minimal-src.tgz")
+                  ;; this mirror seems to have broken HTTPS:
+                  (string-append
+                   "http://mirror.informatik.uni-tuebingen.de/mirror/racket/"
+                   version "/racket-minimal-src.tgz")))
+       (sha256 "0mwyffw4gcci8wmzxa3j28h03h0gsz55aard8qrk3lri8r2xyg21")))
     (synopsis "Racket without bundled packages such as Dr. Racket")
-    (arguments
-     (substitute-keyword-arguments (package-arguments racket)
-       ((#:phases phases)
-        `(modify-phases ,phases
-           ;; Delete fix that applies to files not included in the minimal package.
-           (delete 'pre-configure)))))
     (inputs
      `(("openssl" ,openssl)
        ("sqlite" ,sqlite)
+       ("sh" ,bash-minimal)
        ("zlib" ,zlib)
        ("zlib:static" ,zlib "static")
        ("lz4" ,lz4)
