diff --git a/pkgs/os-specific/linux/minimal-bootstrap/default.nix b/pkgs/os-specific/linux/minimal-bootstrap/default.nix
index 24b9f735f949..510f0e047ec0 100644
--- a/pkgs/os-specific/linux/minimal-bootstrap/default.nix
+++ b/pkgs/os-specific/linux/minimal-bootstrap/default.nix
@@ -10,7 +10,7 @@ lib.makeScope newScope (self: with self; {
     inherit system;
   };
 
-  inherit (callPackage ./stage0-posix { }) kaem mkKaemDerivation m2libc mescc-tools mescc-tools-extra writeTextFile writeText;
+  inherit (callPackage ./stage0-posix { }) kaem m2libc mescc-tools mescc-tools-extra writeTextFile writeText runCommand;
 
   mes = callPackage ./mes { };
 
diff --git a/pkgs/os-specific/linux/minimal-bootstrap/mes/default.nix b/pkgs/os-specific/linux/minimal-bootstrap/mes/default.nix
index 3e04cc54c1c5..6c179c4fbfec 100644
--- a/pkgs/os-specific/linux/minimal-bootstrap/mes/default.nix
+++ b/pkgs/os-specific/linux/minimal-bootstrap/mes/default.nix
@@ -1,4 +1,4 @@
-{ mkKaemDerivation
+{ runCommand
 , fetchurl
 , writeText
 , m2libc
@@ -19,279 +19,274 @@ let
     sha256 = "06rg6pn4k8smyydwls1abc9h702cri3z65ac9gvc4rxxklpynslk";
   };
 in
-(mkKaemDerivation {
-  pname = "mes";
-  inherit version;
+# Adapted from https://github.com/fosslinux/live-bootstrap/blob/1bc4296091c51f53a5598050c8956d16e945b0f5/sysa/mes-0.24.2/mes-0.24.2.kaem
+(runCommand "mes-${version}" {} ''
+  # Unpack source
+  ungz --file ${src} --output mes.tar
+  mkdir ''${out} ''${out}/bin ''${out}/share
+  cd ''${out}/share
+  untar --non-strict --file ''${NIX_BUILD_TOP}/mes.tar # ignore symlinks
 
-  # Adapted from https://github.com/fosslinux/live-bootstrap/blob/1bc4296091c51f53a5598050c8956d16e945b0f5/sysa/mes-0.24.2/mes-0.24.2.kaem
-  buildPhase = ''
-    # Unpack source
-    ungz --file ${src} --output mes.tar
-    mkdir ''${out} ''${out}/bin ''${out}/share
-    cd ''${out}/share
-    untar --non-strict --file ''${NIX_BUILD_TOP}/mes.tar # ignore symlinks
+  MES_PREFIX=''${out}/share/mes-${version}
+  LIBDIR=''${MES_PREFIX}/lib
 
-    MES_PREFIX=''${out}/share/mes-${version}
-    LIBDIR=''${MES_PREFIX}/lib
+  cd ''${MES_PREFIX}
 
-    cd ''${MES_PREFIX}
+  cp ${./config.h} include/mes/config.h
+  replace --file include/mes/config.h --output include/mes/config.h --match-on @VERSION@ --replace-with ${version}
 
-    cp ${./config.h} include/mes/config.h
-    replace --file include/mes/config.h --output include/mes/config.h --match-on @VERSION@ --replace-with ${version}
+  mkdir include/arch
+  cp include/linux/x86/syscall.h include/arch/syscall.h
+  cp include/linux/x86/kernel-stat.h include/arch/kernel-stat.h
 
-    mkdir include/arch
-    cp include/linux/x86/syscall.h include/arch/syscall.h
-    cp include/linux/x86/kernel-stat.h include/arch/kernel-stat.h
+  # Remove pregenerated files
+  rm mes/module/mes/psyntax.pp mes/module/mes/psyntax.pp.header
 
-    # Remove pregenerated files
-    rm mes/module/mes/psyntax.pp mes/module/mes/psyntax.pp.header
+  # These files are symlinked in the repo
+  cp mes/module/srfi/srfi-9-struct.mes mes/module/srfi/srfi-9.mes
+  cp mes/module/srfi/srfi-9/gnu-struct.mes mes/module/srfi/srfi-9/gnu.mes
 
-    # These files are symlinked in the repo
-    cp mes/module/srfi/srfi-9-struct.mes mes/module/srfi/srfi-9.mes
-    cp mes/module/srfi/srfi-9/gnu-struct.mes mes/module/srfi/srfi-9/gnu.mes
+  # Fixes to support newer M2-Planet
+  catm x86_defs.M1 ${m2libc}/x86/x86_defs.M1 lib/m2/x86/x86_defs.M1
+  cp x86_defs.M1 lib/m2/x86/x86_defs.M1
+  rm x86_defs.M1
 
-    # Fixes to support newer M2-Planet
-    catm x86_defs.M1 ${m2libc}/x86/x86_defs.M1 lib/m2/x86/x86_defs.M1
-    cp x86_defs.M1 lib/m2/x86/x86_defs.M1
-    rm x86_defs.M1
+  # Remove environment impurities
+  __GUILE_LOAD_PATH="\"''${MES_PREFIX}/mes/module:''${MES_PREFIX}/module:${nyaccModules}/module\""
+  boot0_scm=mes/module/mes/boot-0.scm
+  guile_mes=mes/module/mes/guile.mes
+  replace --file ''${boot0_scm} --output ''${boot0_scm} --match-on "(getenv \"GUILE_LOAD_PATH\")" --replace-with ''${__GUILE_LOAD_PATH}
+  replace --file ''${guile_mes} --output ''${guile_mes} --match-on "(getenv \"GUILE_LOAD_PATH\")" --replace-with ''${__GUILE_LOAD_PATH}
 
-    # Remove environment impurities
-    __GUILE_LOAD_PATH="\"''${MES_PREFIX}/mes/module:''${MES_PREFIX}/module:${nyaccModules}/module\""
-    boot0_scm=mes/module/mes/boot-0.scm
-    guile_mes=mes/module/mes/guile.mes
-    replace --file ''${boot0_scm} --output ''${boot0_scm} --match-on "(getenv \"GUILE_LOAD_PATH\")" --replace-with ''${__GUILE_LOAD_PATH}
-    replace --file ''${guile_mes} --output ''${guile_mes} --match-on "(getenv \"GUILE_LOAD_PATH\")" --replace-with ''${__GUILE_LOAD_PATH}
+  module_mescc_scm=module/mescc/mescc.scm
+  replace --file ''${module_mescc_scm} --output ''${module_mescc_scm} --match-on "(getenv \"M1\")" --replace-with "\"${mescc-tools}/bin/M1\""
+  replace --file ''${module_mescc_scm} --output ''${module_mescc_scm} --match-on "(getenv \"HEX2\")" --replace-with "\"${mescc-tools}/bin/hex2\""
+  replace --file ''${module_mescc_scm} --output ''${module_mescc_scm} --match-on "(getenv \"BLOOD_ELF\")" --replace-with "\"${mescc-tools}/bin/blood-elf\""
+  replace --file ''${module_mescc_scm} --output ''${module_mescc_scm} --match-on "(getenv \"srcdest\")" --replace-with "\"''${MES_PREFIX}\""
 
-    module_mescc_scm=module/mescc/mescc.scm
-    replace --file ''${module_mescc_scm} --output ''${module_mescc_scm} --match-on "(getenv \"M1\")" --replace-with "\"${mescc-tools}/bin/M1\""
-    replace --file ''${module_mescc_scm} --output ''${module_mescc_scm} --match-on "(getenv \"HEX2\")" --replace-with "\"${mescc-tools}/bin/hex2\""
-    replace --file ''${module_mescc_scm} --output ''${module_mescc_scm} --match-on "(getenv \"BLOOD_ELF\")" --replace-with "\"${mescc-tools}/bin/blood-elf\""
-    replace --file ''${module_mescc_scm} --output ''${module_mescc_scm} --match-on "(getenv \"srcdest\")" --replace-with "\"''${MES_PREFIX}\""
+  mes_c=src/mes.c
+  replace --file ''${mes_c} --output ''${mes_c} --match-on "getenv (\"MES_PREFIX\")" --replace-with "\"''${MES_PREFIX}\""
+  replace --file ''${mes_c} --output ''${mes_c} --match-on "getenv (\"srcdest\")" --replace-with "\"''${MES_PREFIX}\""
 
-    mes_c=src/mes.c
-    replace --file ''${mes_c} --output ''${mes_c} --match-on "getenv (\"MES_PREFIX\")" --replace-with "\"''${MES_PREFIX}\""
-    replace --file ''${mes_c} --output ''${mes_c} --match-on "getenv (\"srcdest\")" --replace-with "\"''${MES_PREFIX}\""
+  gc_c=src/gc.c
+  replace --file ''${gc_c} --output ''${gc_c} --match-on "getenv (\"MES_ARENA\")" --replace-with "\"100000000\""
+  replace --file ''${gc_c} --output ''${gc_c} --match-on "getenv (\"MES_MAX_ARENA\")" --replace-with "\"100000000\""
+  replace --file ''${gc_c} --output ''${gc_c} --match-on "getenv (\"MES_STACK\")" --replace-with "\"6000000\""
 
-    gc_c=src/gc.c
-    replace --file ''${gc_c} --output ''${gc_c} --match-on "getenv (\"MES_ARENA\")" --replace-with "\"100000000\""
-    replace --file ''${gc_c} --output ''${gc_c} --match-on "getenv (\"MES_MAX_ARENA\")" --replace-with "\"100000000\""
-    replace --file ''${gc_c} --output ''${gc_c} --match-on "getenv (\"MES_STACK\")" --replace-with "\"6000000\""
+  # Create mescc.scm
+  mescc_in=scripts/mescc.scm.in
+  replace --file ''${mescc_in} --output ''${mescc_in} --match-on "(getenv \"MES_PREFIX\")" --replace-with "\"''${MES_PREFIX}\""
+  replace --file ''${mescc_in} --output ''${mescc_in} --match-on "(getenv \"includedir\")" --replace-with "\"''${MES_PREFIX}/include\""
+  replace --file ''${mescc_in} --output ''${mescc_in} --match-on "(getenv \"libdir\")" --replace-with "\"''${MES_PREFIX}/lib\""
+  replace --file ''${mescc_in} --output ''${mescc_in} --match-on @prefix@ --replace-with ''${MES_PREFIX}
+  replace --file ''${mescc_in} --output ''${mescc_in} --match-on @VERSION@ --replace-with ${version}
+  replace --file ''${mescc_in} --output ''${mescc_in} --match-on @mes_cpu@ --replace-with ${ARCH}
+  replace --file ''${mescc_in} --output ''${mescc_in} --match-on @mes_kernel@ --replace-with linux
+  cp ''${mescc_in} ''${out}/bin/mescc.scm
+  chmod 555 ''${out}/bin/mescc.scm
 
-    # Create mescc.scm
-    mescc_in=scripts/mescc.scm.in
-    replace --file ''${mescc_in} --output ''${mescc_in} --match-on "(getenv \"MES_PREFIX\")" --replace-with "\"''${MES_PREFIX}\""
-    replace --file ''${mescc_in} --output ''${mescc_in} --match-on "(getenv \"includedir\")" --replace-with "\"''${MES_PREFIX}/include\""
-    replace --file ''${mescc_in} --output ''${mescc_in} --match-on "(getenv \"libdir\")" --replace-with "\"''${MES_PREFIX}/lib\""
-    replace --file ''${mescc_in} --output ''${mescc_in} --match-on @prefix@ --replace-with ''${MES_PREFIX}
-    replace --file ''${mescc_in} --output ''${mescc_in} --match-on @VERSION@ --replace-with ${version}
-    replace --file ''${mescc_in} --output ''${mescc_in} --match-on @mes_cpu@ --replace-with ${ARCH}
-    replace --file ''${mescc_in} --output ''${mescc_in} --match-on @mes_kernel@ --replace-with linux
-    cp ''${mescc_in} ''${out}/bin/mescc.scm
-    chmod 555 ''${out}/bin/mescc.scm
-
-    # Build mes-m2
-    mes_cpu=${ARCH}
-    stage0_cpu=${ARCH}
-    kaem --verbose --strict --file kaem.run
-    cp bin/mes-m2 ''${out}/bin/mes-m2
-    chmod 555 ''${out}/bin/mes-m2
+  # Build mes-m2
+  mes_cpu=${ARCH}
+  stage0_cpu=${ARCH}
+  kaem --verbose --strict --file kaem.run
+  cp bin/mes-m2 ''${out}/bin/mes-m2
+  chmod 555 ''${out}/bin/mes-m2
 
 
-    # Recompile Mes and Mes C library using mes-m2 bootstrapped Mes
-    cd ''${NIX_BUILD_TOP}
-    alias mescc="''${out}/bin/mes-m2 -e main ''${out}/bin/mescc.scm -D HAVE_CONFIG_H=1 -I ''${MES_PREFIX}/include -I ''${MES_PREFIX}/include/linux/x86 -c"
+  # Recompile Mes and Mes C library using mes-m2 bootstrapped Mes
+  cd ''${NIX_BUILD_TOP}
+  alias mescc="''${out}/bin/mes-m2 -e main ''${out}/bin/mescc.scm -D HAVE_CONFIG_H=1 -I ''${MES_PREFIX}/include -I ''${MES_PREFIX}/include/linux/x86 -c"
 
-    # Start with crt1.o
-    mescc ''${MES_PREFIX}/lib/linux/x86-mes-mescc/crt1.c
+  # Start with crt1.o
+  mescc ''${MES_PREFIX}/lib/linux/x86-mes-mescc/crt1.c
 
-    # Now for libc-mini.a
-    mescc ''${MES_PREFIX}/lib/mes/eputs.c
-    mescc ''${MES_PREFIX}/lib/mes/oputs.c
-    mescc ''${MES_PREFIX}/lib/mes/globals.c
-    mescc ''${MES_PREFIX}/lib/stdlib/exit.c
-    mescc ''${MES_PREFIX}/lib/linux/x86-mes-mescc/_exit.c
-    mescc ''${MES_PREFIX}/lib/linux/x86-mes-mescc/_write.c
-    mescc ''${MES_PREFIX}/lib/stdlib/puts.c
-    mescc ''${MES_PREFIX}/lib/string/strlen.c
-    mescc ''${MES_PREFIX}/lib/mes/mini-write.c
-    catm libc-mini.a eputs.o oputs.o globals.o exit.o _exit.o _write.o puts.o strlen.o mini-write.o
-    catm libc-mini.s eputs.s oputs.s globals.s exit.s _exit.s _write.s puts.s strlen.s mini-write.s
+  # Now for libc-mini.a
+  mescc ''${MES_PREFIX}/lib/mes/eputs.c
+  mescc ''${MES_PREFIX}/lib/mes/oputs.c
+  mescc ''${MES_PREFIX}/lib/mes/globals.c
+  mescc ''${MES_PREFIX}/lib/stdlib/exit.c
+  mescc ''${MES_PREFIX}/lib/linux/x86-mes-mescc/_exit.c
+  mescc ''${MES_PREFIX}/lib/linux/x86-mes-mescc/_write.c
+  mescc ''${MES_PREFIX}/lib/stdlib/puts.c
+  mescc ''${MES_PREFIX}/lib/string/strlen.c
+  mescc ''${MES_PREFIX}/lib/mes/mini-write.c
+  catm libc-mini.a eputs.o oputs.o globals.o exit.o _exit.o _write.o puts.o strlen.o mini-write.o
+  catm libc-mini.s eputs.s oputs.s globals.s exit.s _exit.s _write.s puts.s strlen.s mini-write.s
 
-    # libmescc.a
-    mescc ''${MES_PREFIX}/lib/linux/x86-mes-mescc/syscall-internal.c
-    catm libmescc.a globals.o syscall-internal.o
-    catm libmescc.s globals.s syscall-internal.s
+  # libmescc.a
+  mescc ''${MES_PREFIX}/lib/linux/x86-mes-mescc/syscall-internal.c
+  catm libmescc.a globals.o syscall-internal.o
+  catm libmescc.s globals.s syscall-internal.s
 
-    # libc.a
-    mescc ''${MES_PREFIX}/lib/ctype/isnumber.c
-    mescc ''${MES_PREFIX}/lib/mes/abtol.c
-    mescc ''${MES_PREFIX}/lib/mes/cast.c
-    mescc ''${MES_PREFIX}/lib/mes/eputc.c
-    mescc ''${MES_PREFIX}/lib/mes/fdgetc.c
-    mescc ''${MES_PREFIX}/lib/mes/fdputc.c
-    mescc ''${MES_PREFIX}/lib/mes/fdputs.c
-    mescc ''${MES_PREFIX}/lib/mes/fdungetc.c
-    mescc ''${MES_PREFIX}/lib/mes/itoa.c
-    mescc ''${MES_PREFIX}/lib/mes/ltoa.c
-    mescc ''${MES_PREFIX}/lib/mes/ltoab.c
-    mescc ''${MES_PREFIX}/lib/mes/mes_open.c
-    mescc ''${MES_PREFIX}/lib/mes/ntoab.c
-    mescc ''${MES_PREFIX}/lib/mes/oputc.c
-    mescc ''${MES_PREFIX}/lib/mes/ultoa.c
-    mescc ''${MES_PREFIX}/lib/mes/utoa.c
-    mescc ''${MES_PREFIX}/lib/ctype/isdigit.c
-    mescc ''${MES_PREFIX}/lib/ctype/isspace.c
-    mescc ''${MES_PREFIX}/lib/ctype/isxdigit.c
-    mescc ''${MES_PREFIX}/lib/mes/assert_msg.c
-    mescc ''${MES_PREFIX}/lib/posix/write.c
-    mescc ''${MES_PREFIX}/lib/stdlib/atoi.c
-    mescc ''${MES_PREFIX}/lib/linux/lseek.c
-    mescc ''${MES_PREFIX}/lib/mes/__assert_fail.c
-    mescc ''${MES_PREFIX}/lib/mes/__buffered_read.c
-    mescc ''${MES_PREFIX}/lib/mes/__mes_debug.c
-    mescc ''${MES_PREFIX}/lib/posix/execv.c
-    mescc ''${MES_PREFIX}/lib/posix/getcwd.c
-    mescc ''${MES_PREFIX}/lib/posix/getenv.c
-    mescc ''${MES_PREFIX}/lib/posix/isatty.c
-    mescc ''${MES_PREFIX}/lib/posix/open.c
-    mescc ''${MES_PREFIX}/lib/posix/buffered-read.c
-    mescc ''${MES_PREFIX}/lib/posix/setenv.c
-    mescc ''${MES_PREFIX}/lib/posix/wait.c
-    mescc ''${MES_PREFIX}/lib/stdio/fgetc.c
-    mescc ''${MES_PREFIX}/lib/stdio/fputc.c
-    mescc ''${MES_PREFIX}/lib/stdio/fputs.c
-    mescc ''${MES_PREFIX}/lib/stdio/getc.c
-    mescc ''${MES_PREFIX}/lib/stdio/getchar.c
-    mescc ''${MES_PREFIX}/lib/stdio/putc.c
-    mescc ''${MES_PREFIX}/lib/stdio/putchar.c
-    mescc ''${MES_PREFIX}/lib/stdio/ungetc.c
-    mescc ''${MES_PREFIX}/lib/stdlib/free.c
-    mescc ''${MES_PREFIX}/lib/stdlib/realloc.c
-    mescc ''${MES_PREFIX}/lib/string/memchr.c
-    mescc ''${MES_PREFIX}/lib/string/memcmp.c
-    mescc ''${MES_PREFIX}/lib/string/memcpy.c
-    mescc ''${MES_PREFIX}/lib/string/memmove.c
-    mescc ''${MES_PREFIX}/lib/string/memset.c
-    mescc ''${MES_PREFIX}/lib/string/strcmp.c
-    mescc ''${MES_PREFIX}/lib/string/strcpy.c
-    mescc ''${MES_PREFIX}/lib/string/strncmp.c
-    mescc ''${MES_PREFIX}/lib/posix/raise.c
-    mescc ''${MES_PREFIX}/lib/linux/access.c
-    mescc ''${MES_PREFIX}/lib/linux/brk.c
-    mescc ''${MES_PREFIX}/lib/linux/chmod.c
-    mescc ''${MES_PREFIX}/lib/linux/clock_gettime.c
-    mescc ''${MES_PREFIX}/lib/linux/dup.c
-    mescc ''${MES_PREFIX}/lib/linux/dup2.c
-    mescc ''${MES_PREFIX}/lib/linux/execve.c
-    mescc ''${MES_PREFIX}/lib/linux/fork.c
-    mescc ''${MES_PREFIX}/lib/linux/fsync.c
-    mescc ''${MES_PREFIX}/lib/linux/_getcwd.c
-    mescc ''${MES_PREFIX}/lib/linux/gettimeofday.c
-    mescc ''${MES_PREFIX}/lib/linux/ioctl3.c
-    mescc ''${MES_PREFIX}/lib/linux/malloc.c
-    mescc ''${MES_PREFIX}/lib/linux/_open3.c
-    mescc ''${MES_PREFIX}/lib/linux/_read.c
-    mescc ''${MES_PREFIX}/lib/linux/time.c
-    mescc ''${MES_PREFIX}/lib/linux/unlink.c
-    mescc ''${MES_PREFIX}/lib/linux/waitpid.c
-    mescc ''${MES_PREFIX}/lib/linux/x86-mes-mescc/syscall.c
-    mescc ''${MES_PREFIX}/lib/linux/getpid.c
-    mescc ''${MES_PREFIX}/lib/linux/kill.c
-    catm libc.a eputs.o oputs.o globals.o exit.o _exit.o _write.o puts.o strlen.o isnumber.o abtol.o cast.o eputc.o fdgetc.o fdputc.o fdputs.o fdungetc.o itoa.o ltoa.o ltoab.o mes_open.o ntoab.o oputc.o ultoa.o utoa.o isdigit.o isspace.o isxdigit.o assert_msg.o write.o atoi.o lseek.o __assert_fail.o __buffered_read.o __mes_debug.o execv.o getcwd.o getenv.o isatty.o open.o buffered-read.o setenv.o wait.o fgetc.o fputc.o fputs.o getc.o getchar.o putc.o putchar.o ungetc.o free.o malloc.o realloc.o memchr.o memcmp.o memcpy.o memmove.o memset.o strcmp.o strcpy.o strncmp.o raise.o access.o brk.o chmod.o clock_gettime.o dup.o dup2.o execve.o fork.o fsync.o _getcwd.o gettimeofday.o ioctl3.o _open3.o _read.o time.o unlink.o waitpid.o syscall.o getpid.o kill.o
-    catm libc.s eputs.s oputs.s globals.s exit.s _exit.s _write.s puts.s strlen.s isnumber.s abtol.s cast.s eputc.s fdgetc.s fdputc.s fdputs.s fdungetc.s itoa.s ltoa.s ltoab.s mes_open.s ntoab.s oputc.s ultoa.s utoa.s isdigit.s isspace.s isxdigit.s assert_msg.s write.s atoi.s lseek.s __assert_fail.s __buffered_read.s __mes_debug.s execv.s getcwd.s getenv.s isatty.s open.s buffered-read.s setenv.s wait.s fgetc.s fputc.s fputs.s getc.s getchar.s putc.s putchar.s ungetc.s free.s malloc.s realloc.s memchr.s memcmp.s memcpy.s memmove.s memset.s strcmp.s strcpy.s strncmp.s raise.s access.s brk.s chmod.s clock_gettime.s dup.s dup2.s execve.s fork.s fsync.s _getcwd.s gettimeofday.s ioctl3.s _open3.s _read.s time.s unlink.s waitpid.s syscall.s getpid.s kill.s
+  # libc.a
+  mescc ''${MES_PREFIX}/lib/ctype/isnumber.c
+  mescc ''${MES_PREFIX}/lib/mes/abtol.c
+  mescc ''${MES_PREFIX}/lib/mes/cast.c
+  mescc ''${MES_PREFIX}/lib/mes/eputc.c
+  mescc ''${MES_PREFIX}/lib/mes/fdgetc.c
+  mescc ''${MES_PREFIX}/lib/mes/fdputc.c
+  mescc ''${MES_PREFIX}/lib/mes/fdputs.c
+  mescc ''${MES_PREFIX}/lib/mes/fdungetc.c
+  mescc ''${MES_PREFIX}/lib/mes/itoa.c
+  mescc ''${MES_PREFIX}/lib/mes/ltoa.c
+  mescc ''${MES_PREFIX}/lib/mes/ltoab.c
+  mescc ''${MES_PREFIX}/lib/mes/mes_open.c
+  mescc ''${MES_PREFIX}/lib/mes/ntoab.c
+  mescc ''${MES_PREFIX}/lib/mes/oputc.c
+  mescc ''${MES_PREFIX}/lib/mes/ultoa.c
+  mescc ''${MES_PREFIX}/lib/mes/utoa.c
+  mescc ''${MES_PREFIX}/lib/ctype/isdigit.c
+  mescc ''${MES_PREFIX}/lib/ctype/isspace.c
+  mescc ''${MES_PREFIX}/lib/ctype/isxdigit.c
+  mescc ''${MES_PREFIX}/lib/mes/assert_msg.c
+  mescc ''${MES_PREFIX}/lib/posix/write.c
+  mescc ''${MES_PREFIX}/lib/stdlib/atoi.c
+  mescc ''${MES_PREFIX}/lib/linux/lseek.c
+  mescc ''${MES_PREFIX}/lib/mes/__assert_fail.c
+  mescc ''${MES_PREFIX}/lib/mes/__buffered_read.c
+  mescc ''${MES_PREFIX}/lib/mes/__mes_debug.c
+  mescc ''${MES_PREFIX}/lib/posix/execv.c
+  mescc ''${MES_PREFIX}/lib/posix/getcwd.c
+  mescc ''${MES_PREFIX}/lib/posix/getenv.c
+  mescc ''${MES_PREFIX}/lib/posix/isatty.c
+  mescc ''${MES_PREFIX}/lib/posix/open.c
+  mescc ''${MES_PREFIX}/lib/posix/buffered-read.c
+  mescc ''${MES_PREFIX}/lib/posix/setenv.c
+  mescc ''${MES_PREFIX}/lib/posix/wait.c
+  mescc ''${MES_PREFIX}/lib/stdio/fgetc.c
+  mescc ''${MES_PREFIX}/lib/stdio/fputc.c
+  mescc ''${MES_PREFIX}/lib/stdio/fputs.c
+  mescc ''${MES_PREFIX}/lib/stdio/getc.c
+  mescc ''${MES_PREFIX}/lib/stdio/getchar.c
+  mescc ''${MES_PREFIX}/lib/stdio/putc.c
+  mescc ''${MES_PREFIX}/lib/stdio/putchar.c
+  mescc ''${MES_PREFIX}/lib/stdio/ungetc.c
+  mescc ''${MES_PREFIX}/lib/stdlib/free.c
+  mescc ''${MES_PREFIX}/lib/stdlib/realloc.c
+  mescc ''${MES_PREFIX}/lib/string/memchr.c
+  mescc ''${MES_PREFIX}/lib/string/memcmp.c
+  mescc ''${MES_PREFIX}/lib/string/memcpy.c
+  mescc ''${MES_PREFIX}/lib/string/memmove.c
+  mescc ''${MES_PREFIX}/lib/string/memset.c
+  mescc ''${MES_PREFIX}/lib/string/strcmp.c
+  mescc ''${MES_PREFIX}/lib/string/strcpy.c
+  mescc ''${MES_PREFIX}/lib/string/strncmp.c
+  mescc ''${MES_PREFIX}/lib/posix/raise.c
+  mescc ''${MES_PREFIX}/lib/linux/access.c
+  mescc ''${MES_PREFIX}/lib/linux/brk.c
+  mescc ''${MES_PREFIX}/lib/linux/chmod.c
+  mescc ''${MES_PREFIX}/lib/linux/clock_gettime.c
+  mescc ''${MES_PREFIX}/lib/linux/dup.c
+  mescc ''${MES_PREFIX}/lib/linux/dup2.c
+  mescc ''${MES_PREFIX}/lib/linux/execve.c
+  mescc ''${MES_PREFIX}/lib/linux/fork.c
+  mescc ''${MES_PREFIX}/lib/linux/fsync.c
+  mescc ''${MES_PREFIX}/lib/linux/_getcwd.c
+  mescc ''${MES_PREFIX}/lib/linux/gettimeofday.c
+  mescc ''${MES_PREFIX}/lib/linux/ioctl3.c
+  mescc ''${MES_PREFIX}/lib/linux/malloc.c
+  mescc ''${MES_PREFIX}/lib/linux/_open3.c
+  mescc ''${MES_PREFIX}/lib/linux/_read.c
+  mescc ''${MES_PREFIX}/lib/linux/time.c
+  mescc ''${MES_PREFIX}/lib/linux/unlink.c
+  mescc ''${MES_PREFIX}/lib/linux/waitpid.c
+  mescc ''${MES_PREFIX}/lib/linux/x86-mes-mescc/syscall.c
+  mescc ''${MES_PREFIX}/lib/linux/getpid.c
+  mescc ''${MES_PREFIX}/lib/linux/kill.c
+  catm libc.a eputs.o oputs.o globals.o exit.o _exit.o _write.o puts.o strlen.o isnumber.o abtol.o cast.o eputc.o fdgetc.o fdputc.o fdputs.o fdungetc.o itoa.o ltoa.o ltoab.o mes_open.o ntoab.o oputc.o ultoa.o utoa.o isdigit.o isspace.o isxdigit.o assert_msg.o write.o atoi.o lseek.o __assert_fail.o __buffered_read.o __mes_debug.o execv.o getcwd.o getenv.o isatty.o open.o buffered-read.o setenv.o wait.o fgetc.o fputc.o fputs.o getc.o getchar.o putc.o putchar.o ungetc.o free.o malloc.o realloc.o memchr.o memcmp.o memcpy.o memmove.o memset.o strcmp.o strcpy.o strncmp.o raise.o access.o brk.o chmod.o clock_gettime.o dup.o dup2.o execve.o fork.o fsync.o _getcwd.o gettimeofday.o ioctl3.o _open3.o _read.o time.o unlink.o waitpid.o syscall.o getpid.o kill.o
+  catm libc.s eputs.s oputs.s globals.s exit.s _exit.s _write.s puts.s strlen.s isnumber.s abtol.s cast.s eputc.s fdgetc.s fdputc.s fdputs.s fdungetc.s itoa.s ltoa.s ltoab.s mes_open.s ntoab.s oputc.s ultoa.s utoa.s isdigit.s isspace.s isxdigit.s assert_msg.s write.s atoi.s lseek.s __assert_fail.s __buffered_read.s __mes_debug.s execv.s getcwd.s getenv.s isatty.s open.s buffered-read.s setenv.s wait.s fgetc.s fputc.s fputs.s getc.s getchar.s putc.s putchar.s ungetc.s free.s malloc.s realloc.s memchr.s memcmp.s memcpy.s memmove.s memset.s strcmp.s strcpy.s strncmp.s raise.s access.s brk.s chmod.s clock_gettime.s dup.s dup2.s execve.s fork.s fsync.s _getcwd.s gettimeofday.s ioctl3.s _open3.s _read.s time.s unlink.s waitpid.s syscall.s getpid.s kill.s
 
-    # libc+tcc.a
-    mescc ''${MES_PREFIX}/lib/ctype/islower.c
-    mescc ''${MES_PREFIX}/lib/ctype/isupper.c
-    mescc ''${MES_PREFIX}/lib/ctype/tolower.c
-    mescc ''${MES_PREFIX}/lib/ctype/toupper.c
-    mescc ''${MES_PREFIX}/lib/mes/abtod.c
-    mescc ''${MES_PREFIX}/lib/mes/dtoab.c
-    mescc ''${MES_PREFIX}/lib/mes/search-path.c
-    mescc ''${MES_PREFIX}/lib/posix/execvp.c
-    mescc ''${MES_PREFIX}/lib/stdio/fclose.c
-    mescc ''${MES_PREFIX}/lib/stdio/fdopen.c
-    mescc ''${MES_PREFIX}/lib/stdio/ferror.c
-    mescc ''${MES_PREFIX}/lib/stdio/fflush.c
-    mescc ''${MES_PREFIX}/lib/stdio/fopen.c
-    mescc ''${MES_PREFIX}/lib/stdio/fprintf.c
-    mescc ''${MES_PREFIX}/lib/stdio/fread.c
-    mescc ''${MES_PREFIX}/lib/stdio/fseek.c
-    mescc ''${MES_PREFIX}/lib/stdio/ftell.c
-    mescc ''${MES_PREFIX}/lib/stdio/fwrite.c
-    mescc ''${MES_PREFIX}/lib/stdio/printf.c
-    mescc ''${MES_PREFIX}/lib/stdio/remove.c
-    mescc ''${MES_PREFIX}/lib/stdio/snprintf.c
-    mescc ''${MES_PREFIX}/lib/stdio/sprintf.c
-    mescc ''${MES_PREFIX}/lib/stdio/sscanf.c
-    mescc ''${MES_PREFIX}/lib/stdio/vfprintf.c
-    mescc ''${MES_PREFIX}/lib/stdio/vprintf.c
-    mescc ''${MES_PREFIX}/lib/stdio/vsnprintf.c
-    mescc ''${MES_PREFIX}/lib/stdio/vsprintf.c
-    mescc ''${MES_PREFIX}/lib/stdio/vsscanf.c
-    mescc ''${MES_PREFIX}/lib/stdlib/calloc.c
-    mescc ''${MES_PREFIX}/lib/stdlib/qsort.c
-    mescc ''${MES_PREFIX}/lib/stdlib/strtod.c
-    mescc ''${MES_PREFIX}/lib/stdlib/strtof.c
-    mescc ''${MES_PREFIX}/lib/stdlib/strtol.c
-    mescc ''${MES_PREFIX}/lib/stdlib/strtold.c
-    mescc ''${MES_PREFIX}/lib/stdlib/strtoll.c
-    mescc ''${MES_PREFIX}/lib/stdlib/strtoul.c
-    mescc ''${MES_PREFIX}/lib/stdlib/strtoull.c
-    mescc ''${MES_PREFIX}/lib/string/memmem.c
-    mescc ''${MES_PREFIX}/lib/string/strcat.c
-    mescc ''${MES_PREFIX}/lib/string/strchr.c
-    mescc ''${MES_PREFIX}/lib/string/strlwr.c
-    mescc ''${MES_PREFIX}/lib/string/strncpy.c
-    mescc ''${MES_PREFIX}/lib/string/strrchr.c
-    mescc ''${MES_PREFIX}/lib/string/strstr.c
-    mescc ''${MES_PREFIX}/lib/string/strupr.c
-    mescc ''${MES_PREFIX}/lib/stub/sigaction.c
-    mescc ''${MES_PREFIX}/lib/stub/ldexp.c
-    mescc ''${MES_PREFIX}/lib/stub/mprotect.c
-    mescc ''${MES_PREFIX}/lib/stub/localtime.c
-    mescc ''${MES_PREFIX}/lib/stub/sigemptyset.c
-    mescc ''${MES_PREFIX}/lib/x86-mes-mescc/setjmp.c
-    mescc ''${MES_PREFIX}/lib/linux/close.c
-    mescc ''${MES_PREFIX}/lib/linux/rmdir.c
-    mescc ''${MES_PREFIX}/lib/linux/stat.c
-    catm libc+tcc.a libc.a islower.o isupper.o tolower.o toupper.o abtod.o dtoab.o search-path.o execvp.o fclose.o fdopen.o ferror.o fflush.o fopen.o fprintf.o fread.o fseek.o ftell.o fwrite.o printf.o remove.o snprintf.o sprintf.o sscanf.o vfprintf.o vprintf.o vsnprintf.o vsprintf.o vsscanf.o calloc.o qsort.o strtod.o strtof.o strtol.o strtold.o strtoll.o strtoul.o strtoull.o memmem.o strcat.o strchr.o strlwr.o strncpy.o strrchr.o strstr.o strupr.o sigaction.o ldexp.o mprotect.o localtime.o sigemptyset.o setjmp.o close.o rmdir.o stat.o
-    catm libc+tcc.s libc.s islower.s isupper.s tolower.s toupper.s abtod.s dtoab.s search-path.s execvp.s fclose.s fdopen.s ferror.s fflush.s fopen.s fprintf.s fread.s fseek.s ftell.s fwrite.s printf.s remove.s snprintf.s sprintf.s sscanf.s vfprintf.s vprintf.s vsnprintf.s vsprintf.s vsscanf.s calloc.s qsort.s strtod.s strtof.s strtol.s strtold.s strtoll.s strtoul.s strtoull.s memmem.s strcat.s strchr.s strlwr.s strncpy.s strrchr.s strstr.s strupr.s sigaction.s ldexp.s mprotect.s localtime.s sigemptyset.s setjmp.s close.s rmdir.s stat.s
+  # libc+tcc.a
+  mescc ''${MES_PREFIX}/lib/ctype/islower.c
+  mescc ''${MES_PREFIX}/lib/ctype/isupper.c
+  mescc ''${MES_PREFIX}/lib/ctype/tolower.c
+  mescc ''${MES_PREFIX}/lib/ctype/toupper.c
+  mescc ''${MES_PREFIX}/lib/mes/abtod.c
+  mescc ''${MES_PREFIX}/lib/mes/dtoab.c
+  mescc ''${MES_PREFIX}/lib/mes/search-path.c
+  mescc ''${MES_PREFIX}/lib/posix/execvp.c
+  mescc ''${MES_PREFIX}/lib/stdio/fclose.c
+  mescc ''${MES_PREFIX}/lib/stdio/fdopen.c
+  mescc ''${MES_PREFIX}/lib/stdio/ferror.c
+  mescc ''${MES_PREFIX}/lib/stdio/fflush.c
+  mescc ''${MES_PREFIX}/lib/stdio/fopen.c
+  mescc ''${MES_PREFIX}/lib/stdio/fprintf.c
+  mescc ''${MES_PREFIX}/lib/stdio/fread.c
+  mescc ''${MES_PREFIX}/lib/stdio/fseek.c
+  mescc ''${MES_PREFIX}/lib/stdio/ftell.c
+  mescc ''${MES_PREFIX}/lib/stdio/fwrite.c
+  mescc ''${MES_PREFIX}/lib/stdio/printf.c
+  mescc ''${MES_PREFIX}/lib/stdio/remove.c
+  mescc ''${MES_PREFIX}/lib/stdio/snprintf.c
+  mescc ''${MES_PREFIX}/lib/stdio/sprintf.c
+  mescc ''${MES_PREFIX}/lib/stdio/sscanf.c
+  mescc ''${MES_PREFIX}/lib/stdio/vfprintf.c
+  mescc ''${MES_PREFIX}/lib/stdio/vprintf.c
+  mescc ''${MES_PREFIX}/lib/stdio/vsnprintf.c
+  mescc ''${MES_PREFIX}/lib/stdio/vsprintf.c
+  mescc ''${MES_PREFIX}/lib/stdio/vsscanf.c
+  mescc ''${MES_PREFIX}/lib/stdlib/calloc.c
+  mescc ''${MES_PREFIX}/lib/stdlib/qsort.c
+  mescc ''${MES_PREFIX}/lib/stdlib/strtod.c
+  mescc ''${MES_PREFIX}/lib/stdlib/strtof.c
+  mescc ''${MES_PREFIX}/lib/stdlib/strtol.c
+  mescc ''${MES_PREFIX}/lib/stdlib/strtold.c
+  mescc ''${MES_PREFIX}/lib/stdlib/strtoll.c
+  mescc ''${MES_PREFIX}/lib/stdlib/strtoul.c
+  mescc ''${MES_PREFIX}/lib/stdlib/strtoull.c
+  mescc ''${MES_PREFIX}/lib/string/memmem.c
+  mescc ''${MES_PREFIX}/lib/string/strcat.c
+  mescc ''${MES_PREFIX}/lib/string/strchr.c
+  mescc ''${MES_PREFIX}/lib/string/strlwr.c
+  mescc ''${MES_PREFIX}/lib/string/strncpy.c
+  mescc ''${MES_PREFIX}/lib/string/strrchr.c
+  mescc ''${MES_PREFIX}/lib/string/strstr.c
+  mescc ''${MES_PREFIX}/lib/string/strupr.c
+  mescc ''${MES_PREFIX}/lib/stub/sigaction.c
+  mescc ''${MES_PREFIX}/lib/stub/ldexp.c
+  mescc ''${MES_PREFIX}/lib/stub/mprotect.c
+  mescc ''${MES_PREFIX}/lib/stub/localtime.c
+  mescc ''${MES_PREFIX}/lib/stub/sigemptyset.c
+  mescc ''${MES_PREFIX}/lib/x86-mes-mescc/setjmp.c
+  mescc ''${MES_PREFIX}/lib/linux/close.c
+  mescc ''${MES_PREFIX}/lib/linux/rmdir.c
+  mescc ''${MES_PREFIX}/lib/linux/stat.c
+  catm libc+tcc.a libc.a islower.o isupper.o tolower.o toupper.o abtod.o dtoab.o search-path.o execvp.o fclose.o fdopen.o ferror.o fflush.o fopen.o fprintf.o fread.o fseek.o ftell.o fwrite.o printf.o remove.o snprintf.o sprintf.o sscanf.o vfprintf.o vprintf.o vsnprintf.o vsprintf.o vsscanf.o calloc.o qsort.o strtod.o strtof.o strtol.o strtold.o strtoll.o strtoul.o strtoull.o memmem.o strcat.o strchr.o strlwr.o strncpy.o strrchr.o strstr.o strupr.o sigaction.o ldexp.o mprotect.o localtime.o sigemptyset.o setjmp.o close.o rmdir.o stat.o
+  catm libc+tcc.s libc.s islower.s isupper.s tolower.s toupper.s abtod.s dtoab.s search-path.s execvp.s fclose.s fdopen.s ferror.s fflush.s fopen.s fprintf.s fread.s fseek.s ftell.s fwrite.s printf.s remove.s snprintf.s sprintf.s sscanf.s vfprintf.s vprintf.s vsnprintf.s vsprintf.s vsscanf.s calloc.s qsort.s strtod.s strtof.s strtol.s strtold.s strtoll.s strtoul.s strtoull.s memmem.s strcat.s strchr.s strlwr.s strncpy.s strrchr.s strstr.s strupr.s sigaction.s ldexp.s mprotect.s localtime.s sigemptyset.s setjmp.s close.s rmdir.s stat.s
 
-    # Build mes itself
-    mescc ''${MES_PREFIX}/src/builtins.c
-    mescc ''${MES_PREFIX}/src/cc.c
-    mescc ''${MES_PREFIX}/src/core.c
-    mescc ''${MES_PREFIX}/src/display.c
-    mescc ''${MES_PREFIX}/src/eval-apply.c
-    mescc ''${MES_PREFIX}/src/gc.c
-    mescc ''${MES_PREFIX}/src/globals.c
-    mescc ''${MES_PREFIX}/src/hash.c
-    mescc ''${MES_PREFIX}/src/lib.c
-    mescc ''${MES_PREFIX}/src/math.c
-    mescc ''${MES_PREFIX}/src/mes.c
-    mescc ''${MES_PREFIX}/src/module.c
-    mescc ''${MES_PREFIX}/src/posix.c
-    mescc ''${MES_PREFIX}/src/reader.c
-    mescc ''${MES_PREFIX}/src/stack.c
-    mescc ''${MES_PREFIX}/src/string.c
-    mescc ''${MES_PREFIX}/src/struct.c
-    mescc ''${MES_PREFIX}/src/symbol.c
-    mescc ''${MES_PREFIX}/src/vector.c
+  # Build mes itself
+  mescc ''${MES_PREFIX}/src/builtins.c
+  mescc ''${MES_PREFIX}/src/cc.c
+  mescc ''${MES_PREFIX}/src/core.c
+  mescc ''${MES_PREFIX}/src/display.c
+  mescc ''${MES_PREFIX}/src/eval-apply.c
+  mescc ''${MES_PREFIX}/src/gc.c
+  mescc ''${MES_PREFIX}/src/globals.c
+  mescc ''${MES_PREFIX}/src/hash.c
+  mescc ''${MES_PREFIX}/src/lib.c
+  mescc ''${MES_PREFIX}/src/math.c
+  mescc ''${MES_PREFIX}/src/mes.c
+  mescc ''${MES_PREFIX}/src/module.c
+  mescc ''${MES_PREFIX}/src/posix.c
+  mescc ''${MES_PREFIX}/src/reader.c
+  mescc ''${MES_PREFIX}/src/stack.c
+  mescc ''${MES_PREFIX}/src/string.c
+  mescc ''${MES_PREFIX}/src/struct.c
+  mescc ''${MES_PREFIX}/src/symbol.c
+  mescc ''${MES_PREFIX}/src/vector.c
 
-    # Install libraries
-    cp libc.a ''${MES_PREFIX}/lib/x86-mes/
-    cp libc+tcc.a ''${MES_PREFIX}/lib/x86-mes/
-    cp libmescc.a ''${MES_PREFIX}/lib/x86-mes/
-    cp libc.s ''${MES_PREFIX}/lib/x86-mes/
-    cp libc+tcc.s ''${MES_PREFIX}/lib/x86-mes/
-    cp libmescc.s ''${MES_PREFIX}/lib/x86-mes/
-    cp crt1.o ''${MES_PREFIX}/lib/x86-mes/
-    cp crt1.s ''${MES_PREFIX}/lib/x86-mes/
+  # Install libraries
+  cp libc.a ''${MES_PREFIX}/lib/x86-mes/
+  cp libc+tcc.a ''${MES_PREFIX}/lib/x86-mes/
+  cp libmescc.a ''${MES_PREFIX}/lib/x86-mes/
+  cp libc.s ''${MES_PREFIX}/lib/x86-mes/
+  cp libc+tcc.s ''${MES_PREFIX}/lib/x86-mes/
+  cp libmescc.s ''${MES_PREFIX}/lib/x86-mes/
+  cp crt1.o ''${MES_PREFIX}/lib/x86-mes/
+  cp crt1.s ''${MES_PREFIX}/lib/x86-mes/
 
-    # Link everything into new mes executable
-    ''${out}/bin/mes-m2 -e main ''${out}/bin/mescc.scm -- --base-address 0x08048000 -L ''${MES_PREFIX}/lib -nostdlib -o ''${out}/bin/mes -L . crt1.o builtins.o cc.o core.o display.o eval-apply.o gc.o globals.o hash.o lib.o math.o mes.o module.o posix.o reader.o stack.o string.o struct.o symbol.o vector.o -lc -lmescc
-  '';
-}) // {
+  # Link everything into new mes executable
+  ''${out}/bin/mes-m2 -e main ''${out}/bin/mescc.scm -- --base-address 0x08048000 -L ''${MES_PREFIX}/lib -nostdlib -o ''${out}/bin/mes -L . crt1.o builtins.o cc.o core.o display.o eval-apply.o gc.o globals.o hash.o lib.o math.o mes.o module.o posix.o reader.o stack.o string.o struct.o symbol.o vector.o -lc -lmescc
+'') // {
   mesPrefix = "/share/mes-${version}";
 }
diff --git a/pkgs/os-specific/linux/minimal-bootstrap/stage0-posix/default.nix b/pkgs/os-specific/linux/minimal-bootstrap/stage0-posix/default.nix
index c26bca378571..ca015991a9d8 100644
--- a/pkgs/os-specific/linux/minimal-bootstrap/stage0-posix/default.nix
+++ b/pkgs/os-specific/linux/minimal-bootstrap/stage0-posix/default.nix
@@ -40,7 +40,7 @@ lib.makeScope newScope (self: with self; {
 
   mescc-tools-extra = callPackage ./mescc-tools-extra { };
 
-  inherit (callPackage ./utils.nix { }) writeTextFile writeText mkKaemDerivation;
+  inherit (callPackage ./utils.nix { }) writeTextFile writeText runCommand;
 
   # Now that mescc-tools-extra is available we can install kaem at /bin/kaem
   # to make it findable in environments
diff --git a/pkgs/os-specific/linux/minimal-bootstrap/stage0-posix/utils.nix b/pkgs/os-specific/linux/minimal-bootstrap/stage0-posix/utils.nix
index 8b013d30b20f..ce579c3d2210 100644
--- a/pkgs/os-specific/linux/minimal-bootstrap/stage0-posix/utils.nix
+++ b/pkgs/os-specific/linux/minimal-bootstrap/stage0-posix/utils.nix
@@ -34,30 +34,18 @@ rec {
 
   writeText = name: text: writeTextFile {inherit name text;};
 
-  mkKaemDerivation = args@{
-    pname ? null,
-    version ? null,
-    name ? null,
-    buildPhase,
-    buildInputs ? [],
-    ...
-  }:
-    assert name == null -> pname != null && version != null;
-    let
-      rname = if name != null then name else "${pname}-${version}";
-    in
+  runCommand = name: env: buildCommand:
     derivation ({
-      inherit system;
-      name = rname;
+      inherit name system;
 
       builder = "${kaem}/bin/kaem";
       args = [
         "--verbose"
         "--strict"
         "--file"
-        (writeText "${rname}-builder" buildPhase)
+        (writeText "${name}-builder" buildCommand)
       ];
 
-      PATH = lib.makeBinPath (buildInputs ++ [ kaem mescc-tools mescc-tools-extra ]);
-    } // (builtins.removeAttrs args [ "pname" "version" "name" "buildPhase" "buildInputs" ]));
+      PATH = lib.makeBinPath ((env.nativeBuildInputs or []) ++ [ kaem mescc-tools mescc-tools-extra ]);
+    } // (builtins.removeAttrs env [ "nativeBuildInputs" ]));
 }
diff --git a/pkgs/os-specific/linux/minimal-bootstrap/tinycc/bootstrappable.nix b/pkgs/os-specific/linux/minimal-bootstrap/tinycc/bootstrappable.nix
index 872295a74072..ba57c794fa4c 100644
--- a/pkgs/os-specific/linux/minimal-bootstrap/tinycc/bootstrappable.nix
+++ b/pkgs/os-specific/linux/minimal-bootstrap/tinycc/bootstrappable.nix
@@ -2,7 +2,7 @@
 # that can be compiled by MesCC
 
 { lib
-, mkKaemDerivation
+, runCommand
 , fetchurl
 , mes
 , buildTinyccN
@@ -15,72 +15,67 @@ let
     sha256 = "1xhn5qgph32dlxp3fkl4d78f21hvlb2r5dpxvh295x8spkbmbrwp";
   };
 
-  mes-tcc = mkKaemDerivation rec {
-    pname = "mes-tcc";
-    version = "0.9.27";
+  mes-tcc = runCommand "mes-tcc-${version}" {} ''
+    # Create config.h
+    catm config.h
 
-    buildPhase = ''
-      # Create config.h
-      catm config.h
+    ${mes}/bin/mes --no-auto-compile -e main ${mes}/bin/mescc.scm -- \
+      -S \
+      -o tcc.s \
+      -I . \
+      -D BOOTSTRAP=1 \
+      -I ${src} \
+      -D TCC_TARGET_I386=1 \
+      -D inline= \
+      -D CONFIG_TCCDIR=\"''${out}/lib\" \
+      -D CONFIG_SYSROOT=\"\" \
+      -D CONFIG_TCC_CRTPREFIX=\"''${out}/lib\" \
+      -D CONFIG_TCC_ELFINTERP=\"/mes/loader\" \
+      -D CONFIG_TCC_SYSINCLUDEPATHS=\"${mes}${mes.mesPrefix}/include\" \
+      -D TCC_LIBGCC=\"${mes}${mes.mesPrefix}/lib/x86-mes/libc.a\" \
+      -D CONFIG_TCC_LIBTCC1_MES=0 \
+      -D CONFIG_TCCBOOT=1 \
+      -D CONFIG_TCC_STATIC=1 \
+      -D CONFIG_USE_LIBGCC=1 \
+      -D TCC_MES_LIBC=1 \
+      -D TCC_VERSION=\"${version}\" \
+      -D ONE_SOURCE=1 \
+      ${src}/tcc.c
 
-      ${mes}/bin/mes --no-auto-compile -e main ${mes}/bin/mescc.scm -- \
-        -S \
-        -o tcc.s \
-        -I . \
-        -D BOOTSTRAP=1 \
-        -I ${src} \
-        -D TCC_TARGET_I386=1 \
-        -D inline= \
-        -D CONFIG_TCCDIR=\"''${out}/lib\" \
-        -D CONFIG_SYSROOT=\"\" \
-        -D CONFIG_TCC_CRTPREFIX=\"''${out}/lib\" \
-        -D CONFIG_TCC_ELFINTERP=\"/mes/loader\" \
-        -D CONFIG_TCC_SYSINCLUDEPATHS=\"${mes}${mes.mesPrefix}/include\" \
-        -D TCC_LIBGCC=\"${mes}${mes.mesPrefix}/lib/x86-mes/libc.a\" \
-        -D CONFIG_TCC_LIBTCC1_MES=0 \
-        -D CONFIG_TCCBOOT=1 \
-        -D CONFIG_TCC_STATIC=1 \
-        -D CONFIG_USE_LIBGCC=1 \
-        -D TCC_MES_LIBC=1 \
-        -D TCC_VERSION=\"${version}\" \
-        -D ONE_SOURCE=1 \
-        ${src}/tcc.c
+    mkdir -p ''${out}/bin
+    ${mes}/bin/mes --no-auto-compile -e main ${mes}/bin/mescc.scm -- \
+      -l c+tcc \
+      -o ''${out}/bin/tcc \
+      tcc.s
 
-      mkdir -p ''${out}/bin
-      ${mes}/bin/mes --no-auto-compile -e main ${mes}/bin/mescc.scm -- \
-        -l c+tcc \
-        -o ''${out}/bin/tcc \
-        tcc.s
+    # Quick test
+    ''${out}/bin/tcc -version
 
-      # Quick test
-      ''${out}/bin/tcc -version
+    # Recompile the mes C library
+    mkdir -p ''${out}/lib
+    cd ${mes}${mes.mesPrefix}
 
-      # Recompile the mes C library
-      mkdir -p ''${out}/lib
-      cd ${mes}${mes.mesPrefix}
+    # crt1.o
+    ''${out}/bin/tcc -c -D HAVE_CONFIG_H=1 -I include -I include/linux/x86 -o ''${out}/lib/crt1.o lib/linux/x86-mes-gcc/crt1.c
 
-      # crt1.o
-      ''${out}/bin/tcc -c -D HAVE_CONFIG_H=1 -I include -I include/linux/x86 -o ''${out}/lib/crt1.o lib/linux/x86-mes-gcc/crt1.c
+    # crtn.o
+    ''${out}/bin/tcc -c -D HAVE_CONFIG_H=1 -I include -I include/linux/x86 -o ''${out}/lib/crtn.o lib/linux/x86-mes-gcc/crtn.c
 
-      # crtn.o
-      ''${out}/bin/tcc -c -D HAVE_CONFIG_H=1 -I include -I include/linux/x86 -o ''${out}/lib/crtn.o lib/linux/x86-mes-gcc/crtn.c
+    # crti.o
+    ''${out}/bin/tcc -c -D HAVE_CONFIG_H=1 -I include -I include/linux/x86 -o ''${out}/lib/crti.o lib/linux/x86-mes-gcc/crti.c
 
-      # crti.o
-      ''${out}/bin/tcc -c -D HAVE_CONFIG_H=1 -I include -I include/linux/x86 -o ''${out}/lib/crti.o lib/linux/x86-mes-gcc/crti.c
+    # libc+gcc.a
+    ''${out}/bin/tcc -c -D HAVE_CONFIG_H=1 -I include -I include/linux/x86 -o ''${TMPDIR}/unified-libc.o ${unified-libc}
+    ''${out}/bin/tcc -ar cr ''${out}/lib/libc.a ''${TMPDIR}/unified-libc.o
 
-      # libc+gcc.a
-      ''${out}/bin/tcc -c -D HAVE_CONFIG_H=1 -I include -I include/linux/x86 -o ''${TMPDIR}/unified-libc.o ${unified-libc}
-      ''${out}/bin/tcc -ar cr ''${out}/lib/libc.a ''${TMPDIR}/unified-libc.o
+    # libtcc1.a
+    ''${out}/bin/tcc -c -D HAVE_CONFIG_H=1 -I include -I include/linux/x86 -o ''${TMPDIR}/libtcc1.o lib/libtcc1.c
+    ''${out}/bin/tcc -ar cr ''${out}/lib/libtcc1.a ''${TMPDIR}/libtcc1.o
 
-      # libtcc1.a
-      ''${out}/bin/tcc -c -D HAVE_CONFIG_H=1 -I include -I include/linux/x86 -o ''${TMPDIR}/libtcc1.o lib/libtcc1.c
-      ''${out}/bin/tcc -ar cr ''${out}/lib/libtcc1.a ''${TMPDIR}/libtcc1.o
-
-      # libgetopt.a
-      ''${out}/bin/tcc -c -D HAVE_CONFIG_H=1 -I include -I include/linux/x86 -o ''${TMPDIR}/getopt.o lib/posix/getopt.c
-      ''${out}/bin/tcc -ar cr ''${out}/lib/libgetopt.a ''${TMPDIR}/getopt.o
-    '';
-  };
+    # libgetopt.a
+    ''${out}/bin/tcc -c -D HAVE_CONFIG_H=1 -I include -I include/linux/x86 -o ''${TMPDIR}/getopt.o lib/posix/getopt.c
+    ''${out}/bin/tcc -ar cr ''${out}/lib/libgetopt.a ''${TMPDIR}/getopt.o
+  '';
 
   boot0-tcc = buildTinyccN {
     pname = "boot0-tcc";
diff --git a/pkgs/os-specific/linux/minimal-bootstrap/tinycc/default.nix b/pkgs/os-specific/linux/minimal-bootstrap/tinycc/default.nix
index f7e8bf7d2f8f..cd1a5397f212 100644
--- a/pkgs/os-specific/linux/minimal-bootstrap/tinycc/default.nix
+++ b/pkgs/os-specific/linux/minimal-bootstrap/tinycc/default.nix
@@ -1,5 +1,5 @@
 { lib
-, mkKaemDerivation
+, runCommand
 , fetchurl
 , callPackage
 , mes
@@ -11,13 +11,10 @@ let
     sha256 = "009xvbiskg2ims2xag8w78yksnrqpm33asq5arxaph05hd59yss0";
   };
 
-  unified-libc = mkKaemDerivation {
-    name = "mes-unified-libc.c";
-    buildPhase = ''
-      cd ${mes}${mes.mesPrefix}/lib
-      catm ''${out} ctype/isalnum.c ctype/isalpha.c ctype/isascii.c ctype/iscntrl.c ctype/isdigit.c ctype/isgraph.c ctype/islower.c ctype/isnumber.c ctype/isprint.c ctype/ispunct.c ctype/isspace.c ctype/isupper.c ctype/isxdigit.c ctype/tolower.c ctype/toupper.c dirent/closedir.c dirent/__getdirentries.c dirent/opendir.c dirent/readdir.c linux/access.c linux/brk.c linux/chdir.c linux/chmod.c linux/clock_gettime.c linux/close.c linux/dup2.c linux/dup.c linux/execve.c linux/fcntl.c linux/fork.c linux/fsync.c linux/fstat.c linux/_getcwd.c linux/getdents.c linux/getegid.c linux/geteuid.c linux/getgid.c linux/getpid.c linux/getppid.c linux/getrusage.c linux/gettimeofday.c linux/getuid.c linux/ioctl.c linux/ioctl3.c linux/kill.c linux/link.c linux/lseek.c linux/lstat.c linux/malloc.c linux/mkdir.c linux/mknod.c linux/nanosleep.c linux/_open3.c linux/pipe.c linux/_read.c linux/readlink.c linux/rename.c linux/rmdir.c linux/setgid.c linux/settimer.c linux/setuid.c linux/signal.c linux/sigprogmask.c linux/symlink.c linux/stat.c linux/time.c linux/unlink.c linux/waitpid.c linux/x86-mes-gcc/_exit.c linux/x86-mes-gcc/syscall.c linux/x86-mes-gcc/_write.c math/ceil.c math/fabs.c math/floor.c mes/abtod.c mes/abtol.c mes/__assert_fail.c mes/assert_msg.c mes/__buffered_read.c mes/cast.c mes/dtoab.c mes/eputc.c mes/eputs.c mes/fdgetc.c mes/fdgets.c mes/fdputc.c mes/fdputs.c mes/fdungetc.c mes/globals.c mes/itoa.c mes/ltoab.c mes/ltoa.c mes/__mes_debug.c mes/mes_open.c mes/ntoab.c mes/oputc.c mes/oputs.c mes/search-path.c mes/ultoa.c mes/utoa.c posix/alarm.c posix/buffered-read.c posix/execl.c posix/execlp.c posix/execv.c posix/execvp.c posix/getcwd.c posix/getenv.c posix/isatty.c posix/mktemp.c posix/open.c posix/raise.c posix/sbrk.c posix/setenv.c posix/sleep.c posix/unsetenv.c posix/wait.c posix/write.c stdio/clearerr.c stdio/fclose.c stdio/fdopen.c stdio/feof.c stdio/ferror.c stdio/fflush.c stdio/fgetc.c stdio/fgets.c stdio/fileno.c stdio/fopen.c stdio/fprintf.c stdio/fputc.c stdio/fputs.c stdio/fread.c stdio/freopen.c stdio/fscanf.c stdio/fseek.c stdio/ftell.c stdio/fwrite.c stdio/getc.c stdio/getchar.c stdio/perror.c stdio/printf.c stdio/putc.c stdio/putchar.c stdio/remove.c stdio/snprintf.c stdio/sprintf.c stdio/sscanf.c stdio/ungetc.c stdio/vfprintf.c stdio/vfscanf.c stdio/vprintf.c stdio/vsnprintf.c stdio/vsprintf.c stdio/vsscanf.c stdlib/abort.c stdlib/abs.c stdlib/alloca.c stdlib/atexit.c stdlib/atof.c stdlib/atoi.c stdlib/atol.c stdlib/calloc.c stdlib/__exit.c stdlib/exit.c stdlib/free.c stdlib/mbstowcs.c stdlib/puts.c stdlib/qsort.c stdlib/realloc.c stdlib/strtod.c stdlib/strtof.c stdlib/strtol.c stdlib/strtold.c stdlib/strtoll.c stdlib/strtoul.c stdlib/strtoull.c string/bcmp.c string/bcopy.c string/bzero.c string/index.c string/memchr.c string/memcmp.c string/memcpy.c string/memmem.c string/memmove.c string/memset.c string/rindex.c string/strcat.c string/strchr.c string/strcmp.c string/strcpy.c string/strcspn.c string/strdup.c string/strerror.c string/strlen.c string/strlwr.c string/strncat.c string/strncmp.c string/strncpy.c string/strpbrk.c string/strrchr.c string/strspn.c string/strstr.c string/strupr.c stub/atan2.c stub/bsearch.c stub/chown.c stub/__cleanup.c stub/cos.c stub/ctime.c stub/exp.c stub/fpurge.c stub/freadahead.c stub/frexp.c stub/getgrgid.c stub/getgrnam.c stub/getlogin.c stub/getpgid.c stub/getpgrp.c stub/getpwnam.c stub/getpwuid.c stub/gmtime.c stub/ldexp.c stub/localtime.c stub/log.c stub/mktime.c stub/modf.c stub/mprotect.c stub/pclose.c stub/popen.c stub/pow.c stub/rand.c stub/rewind.c stub/setbuf.c stub/setgrent.c stub/setlocale.c stub/setvbuf.c stub/sigaction.c stub/sigaddset.c stub/sigblock.c stub/sigdelset.c stub/sigemptyset.c stub/sigsetmask.c stub/sin.c stub/sys_siglist.c stub/system.c stub/sqrt.c stub/strftime.c stub/times.c stub/ttyname.c stub/umask.c stub/utime.c x86-mes-gcc/setjmp.c
-    '';
-  };
+  unified-libc = runCommand "mes-unified-libc.c" {} ''
+    cd ${mes}${mes.mesPrefix}/lib
+    catm ''${out} ctype/isalnum.c ctype/isalpha.c ctype/isascii.c ctype/iscntrl.c ctype/isdigit.c ctype/isgraph.c ctype/islower.c ctype/isnumber.c ctype/isprint.c ctype/ispunct.c ctype/isspace.c ctype/isupper.c ctype/isxdigit.c ctype/tolower.c ctype/toupper.c dirent/closedir.c dirent/__getdirentries.c dirent/opendir.c dirent/readdir.c linux/access.c linux/brk.c linux/chdir.c linux/chmod.c linux/clock_gettime.c linux/close.c linux/dup2.c linux/dup.c linux/execve.c linux/fcntl.c linux/fork.c linux/fsync.c linux/fstat.c linux/_getcwd.c linux/getdents.c linux/getegid.c linux/geteuid.c linux/getgid.c linux/getpid.c linux/getppid.c linux/getrusage.c linux/gettimeofday.c linux/getuid.c linux/ioctl.c linux/ioctl3.c linux/kill.c linux/link.c linux/lseek.c linux/lstat.c linux/malloc.c linux/mkdir.c linux/mknod.c linux/nanosleep.c linux/_open3.c linux/pipe.c linux/_read.c linux/readlink.c linux/rename.c linux/rmdir.c linux/setgid.c linux/settimer.c linux/setuid.c linux/signal.c linux/sigprogmask.c linux/symlink.c linux/stat.c linux/time.c linux/unlink.c linux/waitpid.c linux/x86-mes-gcc/_exit.c linux/x86-mes-gcc/syscall.c linux/x86-mes-gcc/_write.c math/ceil.c math/fabs.c math/floor.c mes/abtod.c mes/abtol.c mes/__assert_fail.c mes/assert_msg.c mes/__buffered_read.c mes/cast.c mes/dtoab.c mes/eputc.c mes/eputs.c mes/fdgetc.c mes/fdgets.c mes/fdputc.c mes/fdputs.c mes/fdungetc.c mes/globals.c mes/itoa.c mes/ltoab.c mes/ltoa.c mes/__mes_debug.c mes/mes_open.c mes/ntoab.c mes/oputc.c mes/oputs.c mes/search-path.c mes/ultoa.c mes/utoa.c posix/alarm.c posix/buffered-read.c posix/execl.c posix/execlp.c posix/execv.c posix/execvp.c posix/getcwd.c posix/getenv.c posix/isatty.c posix/mktemp.c posix/open.c posix/raise.c posix/sbrk.c posix/setenv.c posix/sleep.c posix/unsetenv.c posix/wait.c posix/write.c stdio/clearerr.c stdio/fclose.c stdio/fdopen.c stdio/feof.c stdio/ferror.c stdio/fflush.c stdio/fgetc.c stdio/fgets.c stdio/fileno.c stdio/fopen.c stdio/fprintf.c stdio/fputc.c stdio/fputs.c stdio/fread.c stdio/freopen.c stdio/fscanf.c stdio/fseek.c stdio/ftell.c stdio/fwrite.c stdio/getc.c stdio/getchar.c stdio/perror.c stdio/printf.c stdio/putc.c stdio/putchar.c stdio/remove.c stdio/snprintf.c stdio/sprintf.c stdio/sscanf.c stdio/ungetc.c stdio/vfprintf.c stdio/vfscanf.c stdio/vprintf.c stdio/vsnprintf.c stdio/vsprintf.c stdio/vsscanf.c stdlib/abort.c stdlib/abs.c stdlib/alloca.c stdlib/atexit.c stdlib/atof.c stdlib/atoi.c stdlib/atol.c stdlib/calloc.c stdlib/__exit.c stdlib/exit.c stdlib/free.c stdlib/mbstowcs.c stdlib/puts.c stdlib/qsort.c stdlib/realloc.c stdlib/strtod.c stdlib/strtof.c stdlib/strtol.c stdlib/strtold.c stdlib/strtoll.c stdlib/strtoul.c stdlib/strtoull.c string/bcmp.c string/bcopy.c string/bzero.c string/index.c string/memchr.c string/memcmp.c string/memcpy.c string/memmem.c string/memmove.c string/memset.c string/rindex.c string/strcat.c string/strchr.c string/strcmp.c string/strcpy.c string/strcspn.c string/strdup.c string/strerror.c string/strlen.c string/strlwr.c string/strncat.c string/strncmp.c string/strncpy.c string/strpbrk.c string/strrchr.c string/strspn.c string/strstr.c string/strupr.c stub/atan2.c stub/bsearch.c stub/chown.c stub/__cleanup.c stub/cos.c stub/ctime.c stub/exp.c stub/fpurge.c stub/freadahead.c stub/frexp.c stub/getgrgid.c stub/getgrnam.c stub/getlogin.c stub/getpgid.c stub/getpgrp.c stub/getpwnam.c stub/getpwuid.c stub/gmtime.c stub/ldexp.c stub/localtime.c stub/log.c stub/mktime.c stub/modf.c stub/mprotect.c stub/pclose.c stub/popen.c stub/pow.c stub/rand.c stub/rewind.c stub/setbuf.c stub/setgrent.c stub/setlocale.c stub/setvbuf.c stub/sigaction.c stub/sigaddset.c stub/sigblock.c stub/sigdelset.c stub/sigemptyset.c stub/sigsetmask.c stub/sin.c stub/sys_siglist.c stub/system.c stub/sqrt.c stub/strftime.c stub/times.c stub/ttyname.c stub/umask.c stub/utime.c x86-mes-gcc/setjmp.c
+  '';
 
   buildTinyccN = {
     pname,
@@ -31,64 +28,57 @@ let
       options = lib.strings.concatStringsSep " " buildOptions;
       libtccOptions = lib.strings.concatStringsSep " " libtccBuildOptions;
     in
-    mkKaemDerivation {
-      inherit pname version;
-      buildPhase = ''
-        catm config.h
-        mkdir -p ''${out}/bin ''${out}/lib
-        ${prev}/bin/tcc \
-          -g \
-          -v \
-          -static \
-          -o ''${out}/bin/tcc \
-          -D BOOTSTRAP=1 \
-          ${options} \
-          -I . \
-          -I ${src} \
-          -D TCC_TARGET_I386=1 \
-          -D CONFIG_TCCDIR=\"''${out}/lib\" \
-          -D CONFIG_TCC_CRTPREFIX=\"''${out}/lib\" \
-          -D CONFIG_TCC_ELFINTERP=\"\" \
-          -D CONFIG_TCC_LIBPATHS=\"''${out}/lib\" \
-          -D CONFIG_TCC_SYSINCLUDEPATHS=\"${mes}${mes.mesPrefix}/include:${src}/include\" \
-          -D TCC_LIBGCC=\"libc.a\" \
-          -D TCC_LIBTCC1=\"libtcc1.a\" \
-          -D CONFIG_TCCBOOT=1 \
-          -D CONFIG_TCC_STATIC=1 \
-          -D CONFIG_USE_LIBGCC=1 \
-          -D TCC_MES_LIBC=1 \
-          -D TCC_VERSION=\"${version}\" \
-          -D ONE_SOURCE=1 \
-          -L ${prev}/lib \
-          ${src}/tcc.c
+    runCommand "${pname}-${version}" {} ''
+      catm config.h
+      mkdir -p ''${out}/bin ''${out}/lib
+      ${prev}/bin/tcc \
+        -g \
+        -v \
+        -static \
+        -o ''${out}/bin/tcc \
+        -D BOOTSTRAP=1 \
+        ${options} \
+        -I . \
+        -I ${src} \
+        -D TCC_TARGET_I386=1 \
+        -D CONFIG_TCCDIR=\"''${out}/lib\" \
+        -D CONFIG_TCC_CRTPREFIX=\"''${out}/lib\" \
+        -D CONFIG_TCC_ELFINTERP=\"\" \
+        -D CONFIG_TCC_LIBPATHS=\"''${out}/lib\" \
+        -D CONFIG_TCC_SYSINCLUDEPATHS=\"${mes}${mes.mesPrefix}/include:${src}/include\" \
+        -D TCC_LIBGCC=\"libc.a\" \
+        -D TCC_LIBTCC1=\"libtcc1.a\" \
+        -D CONFIG_TCCBOOT=1 \
+        -D CONFIG_TCC_STATIC=1 \
+        -D CONFIG_USE_LIBGCC=1 \
+        -D TCC_MES_LIBC=1 \
+        -D TCC_VERSION=\"${version}\" \
+        -D ONE_SOURCE=1 \
+        -L ${prev}/lib \
+        ${src}/tcc.c
 
-        ''${out}/bin/tcc -v
+      ''${out}/bin/tcc -v
 
-        cd ${mes}${mes.mesPrefix}
-        # Recompile libc: crt{1,n,i}, libtcc.a, libc.a, libgetopt.a
-        ''${out}/bin/tcc -c -D HAVE_CONFIG_H=1 -I include -I include/linux/x86 -o ''${out}/lib/crt1.o lib/linux/x86-mes-gcc/crt1.c
-        ''${out}/bin/tcc -c -D HAVE_CONFIG_H=1 -I include -I include/linux/x86 -o ''${out}/lib/crtn.o lib/linux/x86-mes-gcc/crtn.c
-        ''${out}/bin/tcc -c -D HAVE_CONFIG_H=1 -I include -I include/linux/x86 -o ''${out}/lib/crti.o lib/linux/x86-mes-gcc/crti.c
-        ''${out}/bin/tcc -c -D TCC_TARGET_I386=1 ${libtccOptions} -o ''${TMPDIR}/libtcc1.o ${src}/lib/libtcc1.c
-        ''${out}/bin/tcc -ar cr ''${out}/lib/libtcc1.a ''${TMPDIR}/libtcc1.o
-        ''${out}/bin/tcc -c -D HAVE_CONFIG_H=1 -I include -I include/linux/x86 -o ''${TMPDIR}/unified-libc.o ${unified-libc}
-        ''${out}/bin/tcc -ar cr ''${out}/lib/libc.a ''${TMPDIR}/unified-libc.o
-        ''${out}/bin/tcc -c -D HAVE_CONFIG_H=1 -I include -I include/linux/x86 -o ''${TMPDIR}/getopt.o lib/posix/getopt.c
-        ''${out}/bin/tcc -ar cr ''${out}/lib/libgetopt.a ''${TMPDIR}/getopt.o
-      '';
-    };
+      cd ${mes}${mes.mesPrefix}
+      # Recompile libc: crt{1,n,i}, libtcc.a, libc.a, libgetopt.a
+      ''${out}/bin/tcc -c -D HAVE_CONFIG_H=1 -I include -I include/linux/x86 -o ''${out}/lib/crt1.o lib/linux/x86-mes-gcc/crt1.c
+      ''${out}/bin/tcc -c -D HAVE_CONFIG_H=1 -I include -I include/linux/x86 -o ''${out}/lib/crtn.o lib/linux/x86-mes-gcc/crtn.c
+      ''${out}/bin/tcc -c -D HAVE_CONFIG_H=1 -I include -I include/linux/x86 -o ''${out}/lib/crti.o lib/linux/x86-mes-gcc/crti.c
+      ''${out}/bin/tcc -c -D TCC_TARGET_I386=1 ${libtccOptions} -o ''${TMPDIR}/libtcc1.o ${src}/lib/libtcc1.c
+      ''${out}/bin/tcc -ar cr ''${out}/lib/libtcc1.a ''${TMPDIR}/libtcc1.o
+      ''${out}/bin/tcc -c -D HAVE_CONFIG_H=1 -I include -I include/linux/x86 -o ''${TMPDIR}/unified-libc.o ${unified-libc}
+      ''${out}/bin/tcc -ar cr ''${out}/lib/libc.a ''${TMPDIR}/unified-libc.o
+      ''${out}/bin/tcc -c -D HAVE_CONFIG_H=1 -I include -I include/linux/x86 -o ''${TMPDIR}/getopt.o lib/posix/getopt.c
+      ''${out}/bin/tcc -ar cr ''${out}/lib/libgetopt.a ''${TMPDIR}/getopt.o
+    '';
 
   boot4-tcc = callPackage ./bootstrappable.nix { inherit buildTinyccN unified-libc; };
 
-  tccdefs = mkKaemDerivation {
-    pname = "tccdefs";
-    inherit version;
-    buildPhase = ''
-      mkdir ''${out}
-      ${boot4-tcc}/bin/tcc -static -DC2STR -o c2str ${src}/conftest.c
-      ./c2str ${src}/include/tccdefs.h ''${out}/tccdefs_.h
-    '';
-  };
+  tccdefs = runCommand "tccdefs-${version}" {} ''
+    mkdir ''${out}
+    ${boot4-tcc}/bin/tcc -static -DC2STR -o c2str ${src}/conftest.c
+    ./c2str ${src}/include/tccdefs.h ''${out}/tccdefs_.h
+  '';
 
   boot5-tcc = buildTinyccN {
     pname = "boot5-tcc";