diff --git a/README.md b/README.md
index 02716f8..7df2be5 100644
--- a/README.md
+++ b/README.md
@@ -356,3 +356,6 @@ loading modules.
 We now use `perl` from the previous stage to recreate pre-generated files that
 are shipped in perl 5.003. But for now we still need to use handwritten makefile
 instead of `./Configure` script.
+
+### Part 31: perl 5.004_05
+Yet another version of perl.
diff --git a/SHA256SUMS.sources b/SHA256SUMS.sources
index 3961a5e..3608aee 100644
--- a/SHA256SUMS.sources
+++ b/SHA256SUMS.sources
@@ -15,4 +15,5 @@ a32032bab36208509466654df12f507600dfe0313feebbcd218c32a70bf72a16  grep-2.4.tar.g
 ecb5c6469d732bcf01d6ec1afe9e64f1668caba5bfdb103c28d7f537ba3cdb8a  patch-2.5.9.tar.gz
 1ae43c8d2983404b9eec61c96e3ffa27e7b07e08215c95c015a4ab0095373ef3  perl-5.000.tar.gz
 9fa29beb2fc4a3c373829fc051830796de301f32a719d0b52a400d1719bbd7b1  perl-5.003.tar.gz
+1184478b298978b164a383ed5661e3a117c48ab97d6d0ab7ef614cdbe918b9eb  perl5.004_05.tar.gz
 c6c37e888b136ccefab903c51149f4b7bd659d69d4aea21245f61053a57aa60a  tar-1.12.tar.gz
diff --git a/rootfs.sh b/rootfs.sh
index aacdce6..501cb98 100755
--- a/rootfs.sh
+++ b/rootfs.sh
@@ -196,6 +196,9 @@ get_file https://github.com/Perl/perl5/archive/perl-5.000.tar.gz
 # perl 5.003
 get_file https://github.com/Perl/perl5/archive/perl-5.003.tar.gz
 
+# perl 5.004_05
+get_file https://www.cpan.org/src/5.0/perl5.004_05.tar.gz
+
 # General cleanup
 find tmp -name .git -exec rm -rf \;
 
diff --git a/sysa/perl5.004_05/files/config.h b/sysa/perl5.004_05/files/config.h
new file mode 100644
index 0000000..9b1206b
--- /dev/null
+++ b/sysa/perl5.004_05/files/config.h
@@ -0,0 +1,98 @@
+// SPDX-FileCopyrightText: 2021 Andrius Štikonas <andrius@stikonas.eu>
+
+// SPDX-License-Identifier: GPL-3.0-or-later
+
+#define MEM_ALIGNBYTES 8
+#define BIN "/after/bin"
+#define BYTEORDER 0x4321
+#define CPPSTDIN "tcc -E"
+#define CPPMINUS "-"
+#define HAS_ALARM
+#define HAS_FORK
+#define HAS_MKDIR
+#define HAS_PAUSE
+#define HAS_RMDIR
+#define HAS_STRERROR
+#define HAS_SYS_ERRLIST
+#define Strerror(e) strerror(e)
+
+#define HAS_SYSCALL
+#define HAS_TIMES
+
+#define HAS_VPRINTF
+#define Gid_t gid_t
+
+#define I_DIRENT
+#define Direntry_t struct dirent
+
+#define I_DLFCN
+#define I_FCNTL
+#define I_GRP
+#define I_LIMITS
+#define I_MATH
+#define I_NETINET_IN
+#define I_PWD
+#define I_STDDEF
+#define I_STDLIB
+#define I_STRING
+#define I_SYS_DIR
+#define I_SYS_IOCTL
+#define I_SYS_PARAM
+#define I_SYS_SELECT
+#define I_SYS_STAT
+#define I_SYS_TIMES
+#define I_TERMIOS
+#define I_TIME
+#define I_UNISTD
+#define I_UTIME
+#define I_STDARG
+
+#define INTSIZE 4
+#define Off_t off_t
+
+#define PRIVLIB "/after/lib/perl5"
+
+#define _(args) args
+
+#define RANDBITS 31
+
+#define SCRIPTDIR "/after/bin"
+
+#define SIG_NAME "ZERO","HUP","INT","QUIT","ILL","TRAP","IOT","BUS","FPE","KILL","USR1","SEGV","USR2","PIPE","ALRM","TERM","STKFLT","CHLD","CONT","STOP","TSTP","TTIN","TTOU","URG","XCPU","XFSZ","VTALRM","PROF","WINCH", "IO", "POLL", "PWR", "SYS", "UNUSED"
+#define SIG_NUM 0, 1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15, 16, 17, 18, 19, 20, 21, 22, 23, 24, 25, 26, 27, 28, 29, 30, 31
+
+#define Size_t size_t
+
+#define STDCHAR char
+#define Uid_t uid_t
+
+#define LOC_SED "/after/bin/sed"
+#define ARCHLIB "/after/lib/perl5/"
+
+#define CAT2(a,b) a##b
+#define Gconvert(x,n,t,b) gcvt((x),(n),(b))
+
+#define Time_t time_t
+
+#define SSize_t ssize_t
+
+#define Sigjmp_buf sigjmp_buf
+
+#define Sigsetjmp(buf,save_mask) setjmp(buf)
+#define Siglongjmp(buf,retval) longjmp(buf,retval)
+
+#define Signal_t void
+
+#define OSNAME "linux"
+
+#define PRIVLIB_EXP "/after/lib/perl5/5.004_05"
+
+#undef __DATE__ /* want reproducible build */
+
+#define Malloc_t void *
+#define Free_t void
+
+#define SH_PATH "/bin/sh"
+#define ARCHNAME "i386-linux"
+#define BIN_EXP "/after/bin"
+
diff --git a/sysa/perl5.004_05/mk/main.mk b/sysa/perl5.004_05/mk/main.mk
new file mode 100644
index 0000000..75fb848
--- /dev/null
+++ b/sysa/perl5.004_05/mk/main.mk
@@ -0,0 +1,20 @@
+# SPDX-FileCopyrightText: 2021 Andrius Štikonas <andrius@stikonas.eu>
+
+# SPDX-License-Identifier: GPL-3.0-or-later
+
+CC      = tcc
+
+.PHONY: all
+
+MINIPERL_SRC = av deb doio doop dump globals gv hv mg miniperlmain op perl perlio perly pp pp_ctl pp_hot pp_sys regcomp regexec run scope sv taint toke universal util
+MINIPERL_OBJ = $(addsuffix .o, $(MINIPERL_SRC))
+
+all: miniperl
+
+miniperl: $(MINIPERL_OBJ)
+	$(CC) $(CFLAGS) $^ $(LDFLAGS) -o $@
+
+install: all
+	install miniperl $(PREFIX)/bin/perl
+	mkdir -p $(PREFIX)/lib/perl5/5.004_05
+	mv lib/* $(PREFIX)/lib/perl5/5.004_05/
diff --git a/sysa/perl5.004_05/perl5.004_05.sh b/sysa/perl5.004_05/perl5.004_05.sh
new file mode 100755
index 0000000..11029e2
--- /dev/null
+++ b/sysa/perl5.004_05/perl5.004_05.sh
@@ -0,0 +1,29 @@
+# SPDX-FileCopyrightText: 2021 Andrius Štikonas <andrius@stikonas.eu>
+#
+# SPDX-License-Identifier: GPL-3.0-or-later
+
+src_prepare() {
+    default_src_prepare
+
+    # Regenerate bison files
+    rm perly.c perly.h
+    bison -d perly.y
+    mv perly.tab.c perly.c
+    mv perly.tab.h perly.h
+
+    # tcc messes up floats, which breaks version detection
+    sed -i '/require/d' embed.pl
+
+    # Regenerate other prebuilt header files
+    for file in embed keywords opcode; do
+        rm ${file}.h
+        perl ${file}.pl
+    done
+}
+
+src_install() {
+    default_src_install
+
+    # Remove old perl
+    rm -rf "${PREFIX}"/lib/perl5/5.003
+}
diff --git a/sysa/run.sh b/sysa/run.sh
index 4d7cb89..c545ed1 100755
--- a/sysa/run.sh
+++ b/sysa/run.sh
@@ -47,4 +47,7 @@ build perl-5.000
 # Part 30
 build perl-5.003
 
+# Part 31
+build perl5.004_05
+
 echo "Bootstrapping completed."