diff --git a/steps-guix/guix-1.5.0/pass1.sh b/steps-guix/guix-1.5.0/pass1.sh
index 68b598ff..419226c0 100755
--- a/steps-guix/guix-1.5.0/pass1.sh
+++ b/steps-guix/guix-1.5.0/pass1.sh
@@ -27,6 +27,8 @@ src_prepare() {
         -e "s|@EXEC_XZ_HASH@|${EXEC_XZ_HASH}|g" \
         -e "s|@STATIC_BINARIES_SEED_HASH@|${STATIC_BINARIES_SEED_HASH}|g" \
         -e "s|@GUILE_SEED_HASH@|${GUILE_SEED_HASH}|g" \
+        -e "s|@MES_MINIMAL_SEED_HASH@|${MES_MINIMAL_SEED_HASH}|g" \
+        -e "s|@MESCC_TOOLS_SEED_HASH@|${MESCC_TOOLS_SEED_HASH}|g" \
         "${patch_template}" > "${rendered_patch}"
 
     if grep -Eq '@[A-Z0-9_]+@' "${rendered_patch}"; then
@@ -41,8 +43,12 @@ src_prepare() {
     grep -q "${EXEC_BASH_HASH}" "${bootstrap_scm}"
     grep -q "${STATIC_BINARIES_SEED_HASH}" "${bootstrap_scm}"
     grep -q "${GUILE_SEED_HASH}" "${bootstrap_scm}"
+    grep -q "${MES_MINIMAL_SEED_HASH}" "${bootstrap_scm}"
+    grep -q "${MESCC_TOOLS_SEED_HASH}" "${bootstrap_scm}"
     grep -q "All bootstrap binaries must come from local, reproducible distfiles." "${bootstrap_scm}"
     grep -q "%bootstrap-linux-headers-base-urls" "${bootstrap_scm}"
+    grep -q "mes-minimal-stripped-0.19-i686-linux.tar.xz" "${bootstrap_scm}"
+    grep -q "mescc-tools-static-stripped-0.5.2-i686-linux.tar.xz" "${bootstrap_scm}"
     grep -q "Offline bootstrap environment: require explicit channels." guix/channels.scm
 }
 
diff --git a/steps-guix/guix-1.5.0/patches/bootstrap-local-seeds.patch.in b/steps-guix/guix-1.5.0/patches/bootstrap-local-seeds.patch.in
index 91c7209e..71118fa3 100644
--- a/steps-guix/guix-1.5.0/patches/bootstrap-local-seeds.patch.in
+++ b/steps-guix/guix-1.5.0/patches/bootstrap-local-seeds.patch.in
@@ -97,6 +97,76 @@
                                ("armhf-linux"
                                 (base32
                                  "0gf0fn2kbpxkjixkmx5f4z6hv6qpmgixl69zgg74dbsfdfj8jdv5"))
+@@ -675,6 +672,44 @@
+                            (if (not (elf-file? "bin/egrep"))
+                              (substitute* '("bin/egrep" "bin/fgrep")
+                                (("^exec grep") (string-append (getcwd) "/bin/grep"))))
+                            (chmod "bin" #o555))))
++
++(define (bootstrap-mes-minimal-origin system)
++  (origin
++    (method url-fetch)
++    (uri (map (cut string-append <>
++                   "/mes-minimal-stripped-0.19-i686-linux.tar.xz")
++              %bootstrap-base-urls))
++    (sha256
++     (match system
++       ((or "i686-linux" "x86_64-linux")
++        (base32 "@MES_MINIMAL_SEED_HASH@"))
++       (_
++        (base32 "@MES_MINIMAL_SEED_HASH@"))))))
++
++(define %bootstrap-mes-minimal
++  (package-from-tarball "mes-minimal-bootstrap"
++                        bootstrap-mes-minimal-origin
++                        "mes"
++                        "Bootstrap Mes minimal binary seed"))
++
++(define (bootstrap-mescc-tools-origin system)
++  (origin
++    (method url-fetch)
++    (uri (map (cut string-append <>
++                   "/mescc-tools-static-stripped-0.5.2-i686-linux.tar.xz")
++              %bootstrap-base-urls))
++    (sha256
++     (match system
++       ((or "i686-linux" "x86_64-linux")
++        (base32 "@MESCC_TOOLS_SEED_HASH@"))
++       (_
++        (base32 "@MESCC_TOOLS_SEED_HASH@"))))))
++
++(define %bootstrap-mescc-tools
++  (package-from-tarball "mescc-tools-bootstrap"
++                        bootstrap-mescc-tools-origin
++                        "M2-Planet"
++                        "Bootstrap MesCC tools binary seed"))
+ (define-public %bootstrap-linux-libre-headers
+   (package-from-tarball
+@@ -989,11 +1022,15 @@
+   ;; own packages.
+   (match (%current-system)
+     ((or "i686-linux" "x86_64-linux")
+-     `(("linux-libre-headers" ,%bootstrap-linux-libre-headers)))
++     `(("linux-libre-headers" ,%bootstrap-linux-libre-headers)
++       ("mes-minimal" ,%bootstrap-mes-minimal)
++       ("mescc-tools" ,%bootstrap-mescc-tools)))
+     (_
+      `(("libc" ,%bootstrap-glibc)
+        ("gcc" ,%bootstrap-gcc)
+        ("binutils" ,%bootstrap-binutils)
+        ("coreutils&co" ,%bootstrap-coreutils&co)
++       ("mes-minimal" ,%bootstrap-mes-minimal)
++       ("mescc-tools" ,%bootstrap-mescc-tools)
+        ;; In gnu-build-system.scm, we rely on the availability of Bash.
+        ("bash" ,%bootstrap-coreutils&co)))))
+@@ -1005,5 +1042,7 @@
+   `(("libc" ,%bootstrap-glibc)
+     ("gcc" ,%bootstrap-gcc)
+     ("binutils" ,%bootstrap-binutils)
+     ("coreutils&co" ,%bootstrap-coreutils&co)
++    ("mes-minimal" ,%bootstrap-mes-minimal)
++    ("mescc-tools" ,%bootstrap-mescc-tools)
+     ("bash" ,%bootstrap-coreutils&co)))
 --- a/guix/channels.scm
 +++ b/guix/channels.scm
 @@ -194,8 +194,8 @@
diff --git a/steps-guix/xz-5.2.4/pass1.sh b/steps-guix/xz-5.2.4/pass1.sh
index 54173667..e8df790a 100644
--- a/steps-guix/xz-5.2.4/pass1.sh
+++ b/steps-guix/xz-5.2.4/pass1.sh
@@ -2,6 +2,14 @@
 
 SEED_PREFIX="/bootstrap-seeds/xz-5.2.4"
 
+src_prepare() {
+    default
+
+    # Mirror Guix bootstrap static strategy: force libtool-built xz executable
+    # to link with -all-static.
+    sed -i 's/^xz_LDADD =/xz_LDADD = -all-static /' src/xz/Makefile.in
+}
+
 src_configure() {
     ./configure \
         --prefix="${SEED_PREFIX}" \