diff --git a/perl/MANIFEST.SKIP b/perl/MANIFEST.SKIP
index 372742ca..71a24e5c 100644
--- a/perl/MANIFEST.SKIP
+++ b/perl/MANIFEST.SKIP
@@ -25,4 +25,3 @@
 ^Data-MessagePack-[0-9.]+/
 ^\.testenv/test_pp.pl
 ^ppport.h$
-^xshelper.h$
diff --git a/perl/perlxs.h b/perl/perlxs.h
deleted file mode 100644
index 441682de..00000000
--- a/perl/perlxs.h
+++ /dev/null
@@ -1,76 +0,0 @@
-/*
-    perlxs.h - Standard XS header file
-    Copyright (c) Fuji, Goro (gfx)
-*/
-
-#ifdef __cplusplus
-extern "C" {
-#endif
-
-#define PERL_NO_GET_CONTEXT /* we want efficiency */
-#include <EXTERN.h>
-
-#include <perl.h>
-#define NO_XSLOCKS /* for exceptions */
-#include <XSUB.h>
-
-#ifdef __cplusplus
-} /* extern "C" */
-#endif
-
-#include "ppport.h"
-
-/* portability stuff not supported by ppport.h yet */
-
-#ifndef STATIC_INLINE /* from 5.13.4 */
-#   if defined(__GNUC__) || defined(__cplusplus__) || (defined(__STDC_VERSION__) && (__STDC_VERSION__ >= 199901L))
-#       define STATIC_INLINE static inline
-#   else
-#       define STATIC_INLINE static
-#   endif
-#endif /* STATIC_INLINE */
-
-#ifndef __attribute__format__
-#define __attribute__format__(a,b,c) /* nothing */
-#endif
-
-#ifndef LIKELY /* they are just a compiler's hint */
-#define LIKELY(x)   (x)
-#define UNLIKELY(x) (x)
-#endif
-
-#ifndef newSVpvs_share
-#define newSVpvs_share(s) Perl_newSVpvn_share(aTHX_ STR_WITH_LEN(s), 0U)
-#endif
-
-#ifndef get_cvs
-#define get_cvs(name, flags) get_cv(name, flags)
-#endif
-
-#ifndef GvNAME_get
-#define GvNAME_get GvNAME
-#endif
-#ifndef GvNAMELEN_get
-#define GvNAMELEN_get GvNAMELEN
-#endif
-
-#ifndef CvGV_set
-#define CvGV_set(cv, gv) (CvGV(cv) = (gv))
-#endif
-
-/* general utility */
-
-#if PERL_BCDVERSION >= 0x5008005
-#define LooksLikeNumber(x) looks_like_number(x)
-#else
-#define LooksLikeNumber(x) (SvPOKp(x) ? looks_like_number(x) : (I32)SvNIOKp(x))
-#endif
-
-#define newAV_mortal() (AV*)sv_2mortal((SV*)newAV())
-#define newHV_mortal() (HV*)sv_2mortal((SV*)newHV())
-
-#define DECL_BOOT(name) EXTERN_C XS(CAT2(boot_, name))
-#define CALL_BOOT(name) STMT_START {            \
-        PUSHMARK(SP);                           \
-        CALL_FPTR(CAT2(boot_, name))(aTHX_ cv); \
-    } STMT_END
diff --git a/perl/util.h b/perl/util.h
deleted file mode 100644
index 2b4ed072..00000000
--- a/perl/util.h
+++ /dev/null
@@ -1,11 +0,0 @@
-#ifndef __PERL_MSGPACK_UTIL_H__
-#define __PERL_MSGPACK_UTIL_H__
-
-#if __GNUC__ >= 3
-# define INLINE                     inline
-#else
-# define INLINE                     
-#endif
-
-#endif // __PERL_MSGPACK_UTIL_H__
-
diff --git a/perl/xs-src/MessagePack.c b/perl/xs-src/MessagePack.c
index fd1b344d..259fd156 100644
--- a/perl/xs-src/MessagePack.c
+++ b/perl/xs-src/MessagePack.c
@@ -1,14 +1,4 @@
-#ifdef __cplusplus
-extern "C" {
-#endif
-#include "EXTERN.h"
-#include "perl.h"
-#include "XSUB.h"
-#define NEED_newCONSTSUB
-#include "ppport.h"
-#ifdef __cplusplus
-};
-#endif
+#include "xshelper.h"
 
 XS(xs_pack);
 XS(xs_unpack);
@@ -24,13 +14,11 @@ void boot_Data__MessagePack_pack(void);
 
 XS(boot_Data__MessagePack) {
     dXSARGS;
-    HV * stash;
 
     boot_Data__MessagePack_pack();
 
     newXS("Data::MessagePack::pack", xs_pack, __FILE__);
     newXS("Data::MessagePack::unpack", xs_unpack, __FILE__);
-    stash = gv_stashpvn("Data::MessagePack", strlen("Data::MessagePack"), TRUE);
 
     newXS("Data::MessagePack::Unpacker::new",           xs_unpacker_new, __FILE__);
     newXS("Data::MessagePack::Unpacker::execute",       xs_unpacker_execute, __FILE__);
diff --git a/perl/xs-src/unpack.c b/perl/xs-src/unpack.c
index c329e99c..2edfdf79 100644
--- a/perl/xs-src/unpack.c
+++ b/perl/xs-src/unpack.c
@@ -1,15 +1,7 @@
-#ifdef __cplusplus
-extern "C" {
-#endif
-
 #define NEED_newRV_noinc
 #define NEED_sv_2pv_flags
 #include "xshelper.h"
 
-#ifdef __cplusplus
-};
-#endif
-
 typedef struct {
     int finished;
     SV* source;