diff --git a/contrib/guix/libexec/prelude.bash b/contrib/guix/libexec/prelude.bash
index b81799f..2527f91 100644
--- a/contrib/guix/libexec/prelude.bash
+++ b/contrib/guix/libexec/prelude.bash
@@ -51,7 +51,7 @@ fi
 time-machine() {
     # shellcheck disable=SC2086
     guix time-machine --url=https://github.com/tobtoht/guix.git \
-                      --commit=f0bb724211872cd6158fce6162e0b8c73efed126 \
+                      --commit=7bf1d7aeaffba15c4f680f93ae88fbef25427252 \
                       --cores="$JOBS" \
                       --keep-failed \
                       --fallback \
diff --git a/contrib/guix/patches/winpthreads-remap-guix-store.patch b/contrib/guix/patches/winpthreads-remap-guix-store.patch
index 2c12585..e1f1a6e 100644
--- a/contrib/guix/patches/winpthreads-remap-guix-store.patch
+++ b/contrib/guix/patches/winpthreads-remap-guix-store.patch
@@ -6,12 +6,12 @@ the package, map all guix store prefixes to something fixed, e.g. /usr.
 
 --- a/mingw-w64-libraries/winpthreads/Makefile.in
 +++ b/mingw-w64-libraries/winpthreads/Makefile.in
-@@ -454,7 +454,7 @@ top_build_prefix = @top_build_prefix@
+@@ -478,7 +478,7 @@ top_build_prefix = @top_build_prefix@
  top_builddir = @top_builddir@
  top_srcdir = @top_srcdir@
  SUBDIRS = . tests
--AM_CFLAGS = -Wall -DWIN32_LEAN_AND_MEAN
-+AM_CFLAGS = -Wall -DWIN32_LEAN_AND_MEAN $(shell find /gnu/store -maxdepth 1 -mindepth 1 -type d -exec echo -n " -ffile-prefix-map={}=/usr" \;)
+-AM_CFLAGS = -Wall -DWIN32_LEAN_AND_MEAN $(am__append_1)
++AM_CFLAGS = -Wall -DWIN32_LEAN_AND_MEAN $(am__append_1) $(shell find /gnu/store -maxdepth 1 -mindepth 1 -type d -exec echo -n " -ffile-prefix-map={}=/usr" \;)
  ACLOCAL_AMFLAGS = -I m4
  lib_LTLIBRARIES = libwinpthread.la
  include_HEADERS = include/pthread.h include/sched.h include/semaphore.h include/pthread_unistd.h include/pthread_time.h include/pthread_compat.h include/pthread_signal.h