diff --git a/include/mruby.h b/include/mruby.h
index 0fd5ffe5f..a42e0942c 100644
--- a/include/mruby.h
+++ b/include/mruby.h
@@ -1084,7 +1084,7 @@ MRB_API mrb_bool mrb_block_given_p(mrb_state *mrb);
  *
  *      #include <stdio.h>
  *      #include <mruby.h>
- *      #include "mruby/compile.h"
+ *      #include <mruby/compile.h>
  *
  *      int
  *      main()
@@ -1115,7 +1115,7 @@ MRB_API mrb_value mrb_funcall_id(mrb_state *mrb, mrb_value val, mrb_sym mid, mrb
  *
  *      #include <stdio.h>
  *      #include <mruby.h>
- *      #include "mruby/compile.h"
+ *      #include <mruby/compile.h>
  *      int
  *      main()
  *      {
diff --git a/include/mruby/opcode.h b/include/mruby/opcode.h
index 19da77fba..a0f6644cb 100644
--- a/include/mruby/opcode.h
+++ b/include/mruby/opcode.h
@@ -9,7 +9,7 @@
 
 enum mrb_insn {
 #define OPCODE(x,_) OP_ ## x,
-#include "mruby/ops.h"
+#include <mruby/ops.h>
 #undef OPCODE
 };
 
diff --git a/mrbgems/mruby-bin-debugger/tools/mrdb/apistring.h b/mrbgems/mruby-bin-debugger/tools/mrdb/apistring.h
index 33737e7fd..4e77a55ff 100644
--- a/mrbgems/mruby-bin-debugger/tools/mrdb/apistring.h
+++ b/mrbgems/mruby-bin-debugger/tools/mrdb/apistring.h
@@ -5,7 +5,7 @@
 #ifndef APISTRING_H_
 #define APISTRING_H_
 
-#include "mruby.h"
+#include <mruby.h>
 
 /* both functions return a null pointer on failure */
 char *mrdb_strndup(mrb_state *mrb, const char *s, size_t size);
diff --git a/mrbgems/mruby-class-ext/src/class.c b/mrbgems/mruby-class-ext/src/class.c
index 0fa0a4afe..020fe1621 100644
--- a/mrbgems/mruby-class-ext/src/class.c
+++ b/mrbgems/mruby-class-ext/src/class.c
@@ -1,10 +1,10 @@
-#include "mruby.h"
-#include "mruby/class.h"
-#include "mruby/string.h"
-#include "mruby/array.h"
-#include "mruby/proc.h"
-#include "mruby/variable.h"
-#include "mruby/presym.h"
+#include <mruby.h>
+#include <mruby/class.h>
+#include <mruby/string.h>
+#include <mruby/array.h>
+#include <mruby/proc.h>
+#include <mruby/variable.h>
+#include <mruby/presym.h>
 
 static mrb_value
 mod_name(mrb_state *mrb, mrb_value self)
diff --git a/mrbgems/mruby-compiler/core/codegen.c b/mrbgems/mruby-compiler/core/codegen.c
index 552788531..7e5351e64 100644
--- a/mrbgems/mruby-compiler/core/codegen.c
+++ b/mrbgems/mruby-compiler/core/codegen.c
@@ -347,7 +347,7 @@ mrb_decode_insn(const mrb_code *pc)
   switch (insn) {
 #define FETCH_Z() /* empty */
 #define OPCODE(i,x) case OP_ ## i: FETCH_ ## x (); break;
-#include "mruby/ops.h"
+#include <mruby/ops.h>
 #undef OPCODE
   }
   switch (insn) {
@@ -355,7 +355,7 @@ mrb_decode_insn(const mrb_code *pc)
     insn = READ_B();
     switch (insn) {
 #define OPCODE(i,x) case OP_ ## i: FETCH_ ## x ## _1 (); break;
-#include "mruby/ops.h"
+#include <mruby/ops.h>
 #undef OPCODE
     }
     break;
@@ -363,7 +363,7 @@ mrb_decode_insn(const mrb_code *pc)
     insn = READ_B();
     switch (insn) {
 #define OPCODE(i,x) case OP_ ## i: FETCH_ ## x ## _2 (); break;
-#include "mruby/ops.h"
+#include <mruby/ops.h>
 #undef OPCODE
     }
     break;
@@ -371,7 +371,7 @@ mrb_decode_insn(const mrb_code *pc)
     insn = READ_B();
     switch (insn) {
 #define OPCODE(i,x) case OP_ ## i: FETCH_ ## x ## _3 (); break;
-#include "mruby/ops.h"
+#include <mruby/ops.h>
 #undef OPCODE
     }
     break;
@@ -397,7 +397,7 @@ static uint8_t mrb_insn_size[] = {
 #define BBB 4
 #define BS 4
 #define BSS 6
-#include "mruby/ops.h"
+#include <mruby/ops.h>
 #undef B
 #undef BB
 #undef BBB
@@ -411,7 +411,7 @@ static uint8_t mrb_insn_size1[] = {
 #define BBB 5
 #define BS 5
 #define BSS 7
-#include "mruby/ops.h"
+#include <mruby/ops.h>
 #undef B
 #undef BS
 #undef BSS
@@ -421,7 +421,7 @@ static uint8_t mrb_insn_size2[] = {
 #define B 2
 #define BS 4
 #define BSS 6
-#include "mruby/ops.h"
+#include <mruby/ops.h>
 #undef B
 #undef BB
 #undef BBB
@@ -435,7 +435,7 @@ static uint8_t mrb_insn_size2[] = {
 #define BS 5
 #define BSS 7
 static uint8_t mrb_insn_size3[] = {
-#include "mruby/ops.h"
+#include <mruby/ops.h>
 };
 #undef B
 #undef BB
diff --git a/mrbgems/mruby-dir/src/dir.c b/mrbgems/mruby-dir/src/dir.c
index 52d100f2b..1a0451c1e 100644
--- a/mrbgems/mruby-dir/src/dir.c
+++ b/mrbgems/mruby-dir/src/dir.c
@@ -4,12 +4,12 @@
 ** See Copyright Notice in mruby.h
 */
 
-#include "mruby.h"
-#include "mruby/class.h"
-#include "mruby/data.h"
-#include "mruby/error.h"
-#include "mruby/string.h"
-#include "mruby/presym.h"
+#include <mruby.h>
+#include <mruby/class.h>
+#include <mruby/data.h>
+#include <mruby/error.h>
+#include <mruby/string.h>
+#include <mruby/presym.h>
 #include <sys/types.h>
 #if defined(_WIN32) || defined(_WIN64)
   #define MAXPATHLEN 1024
diff --git a/mrbgems/mruby-dir/test/dirtest.c b/mrbgems/mruby-dir/test/dirtest.c
index 34ef34763..2359ee219 100644
--- a/mrbgems/mruby-dir/test/dirtest.c
+++ b/mrbgems/mruby-dir/test/dirtest.c
@@ -31,9 +31,9 @@ int closedir(DIR *dir);
 #include <dirent.h>
 #endif
 
-#include "mruby.h"
-#include "mruby/string.h"
-#include "mruby/variable.h"
+#include <mruby.h>
+#include <mruby/string.h>
+#include <mruby/variable.h>
 
 static void
 make_dir(mrb_state *mrb, const char *name, const char *up)
diff --git a/mrbgems/mruby-errno/src/errno.c b/mrbgems/mruby-errno/src/errno.c
index 71ab61e25..384dc05ea 100644
--- a/mrbgems/mruby-errno/src/errno.c
+++ b/mrbgems/mruby-errno/src/errno.c
@@ -1,12 +1,12 @@
-#include "mruby.h"
-#include "mruby/array.h"
-#include "mruby/class.h"
-#include "mruby/error.h"
-#include "mruby/hash.h"
-#include "mruby/numeric.h"
-#include "mruby/string.h"
-#include "mruby/variable.h"
-#include "mruby/internal.h"
+#include <mruby.h>
+#include <mruby/array.h>
+#include <mruby/class.h>
+#include <mruby/error.h>
+#include <mruby/hash.h>
+#include <mruby/numeric.h>
+#include <mruby/string.h>
+#include <mruby/variable.h>
+#include <mruby/internal.h>
 #include <mruby/presym.h>
 #include <errno.h>
 #include <string.h>
diff --git a/mrbgems/mruby-io/src/file.c b/mrbgems/mruby-io/src/file.c
index 4116d4777..703de791e 100644
--- a/mrbgems/mruby-io/src/file.c
+++ b/mrbgems/mruby-io/src/file.c
@@ -2,13 +2,13 @@
 ** file.c - File class
 */
 
-#include "mruby.h"
-#include "mruby/class.h"
-#include "mruby/data.h"
-#include "mruby/string.h"
-#include "mruby/ext/io.h"
-#include "mruby/error.h"
-#include "mruby/presym.h"
+#include <mruby.h>
+#include <mruby/class.h>
+#include <mruby/data.h>
+#include <mruby/string.h>
+#include <mruby/ext/io.h>
+#include <mruby/error.h>
+#include <mruby/presym.h>
 
 #include <sys/types.h>
 #include <sys/stat.h>
diff --git a/mrbgems/mruby-io/src/file_test.c b/mrbgems/mruby-io/src/file_test.c
index 1d7aa564e..ac9166f94 100644
--- a/mrbgems/mruby-io/src/file_test.c
+++ b/mrbgems/mruby-io/src/file_test.c
@@ -2,12 +2,12 @@
 ** file_test.c - FileTest class
 */
 
-#include "mruby.h"
-#include "mruby/class.h"
-#include "mruby/data.h"
-#include "mruby/string.h"
-#include "mruby/ext/io.h"
-#include "mruby/error.h"
+#include <mruby.h>
+#include <mruby/class.h>
+#include <mruby/data.h>
+#include <mruby/string.h>
+#include <mruby/ext/io.h>
+#include <mruby/error.h>
 
 #include <sys/types.h>
 #include <sys/stat.h>
diff --git a/mrbgems/mruby-io/src/io.c b/mrbgems/mruby-io/src/io.c
index 265716cdf..a3038efb5 100644
--- a/mrbgems/mruby-io/src/io.c
+++ b/mrbgems/mruby-io/src/io.c
@@ -2,17 +2,17 @@
 ** io.c - IO class
 */
 
-#include "mruby.h"
-#include "mruby/array.h"
-#include "mruby/class.h"
-#include "mruby/data.h"
-#include "mruby/hash.h"
-#include "mruby/string.h"
-#include "mruby/variable.h"
-#include "mruby/ext/io.h"
-#include "mruby/error.h"
-#include "mruby/internal.h"
-#include "mruby/presym.h"
+#include <mruby.h>
+#include <mruby/array.h>
+#include <mruby/class.h>
+#include <mruby/data.h>
+#include <mruby/hash.h>
+#include <mruby/string.h>
+#include <mruby/variable.h>
+#include <mruby/ext/io.h>
+#include <mruby/error.h>
+#include <mruby/internal.h>
+#include <mruby/presym.h>
 
 #include <sys/types.h>
 #include <sys/stat.h>
diff --git a/mrbgems/mruby-io/src/mruby_io_gem.c b/mrbgems/mruby-io/src/mruby_io_gem.c
index 6880e6678..8b59383b1 100644
--- a/mrbgems/mruby-io/src/mruby_io_gem.c
+++ b/mrbgems/mruby-io/src/mruby_io_gem.c
@@ -1,4 +1,4 @@
-#include "mruby.h"
+#include <mruby.h>
 
 void mrb_init_io(mrb_state *mrb);
 void mrb_init_file(mrb_state *mrb);
diff --git a/mrbgems/mruby-io/test/mruby_io_test.c b/mrbgems/mruby-io/test/mruby_io_test.c
index bf801323c..c1ff0f8f0 100644
--- a/mrbgems/mruby-io/test/mruby_io_test.c
+++ b/mrbgems/mruby-io/test/mruby_io_test.c
@@ -60,11 +60,11 @@ mkdtemp(char *temp)
 #include <sys/stat.h>
 #include <stdlib.h>
 
-#include "mruby.h"
-#include "mruby/array.h"
-#include "mruby/error.h"
-#include "mruby/string.h"
-#include "mruby/variable.h"
+#include <mruby.h>
+#include <mruby/array.h>
+#include <mruby/error.h>
+#include <mruby/string.h>
+#include <mruby/variable.h>
 #include <mruby/ext/io.h>
 
 static mrb_value
diff --git a/mrbgems/mruby-metaprog/src/metaprog.c b/mrbgems/mruby-metaprog/src/metaprog.c
index 9e962b4a1..9da504afa 100644
--- a/mrbgems/mruby-metaprog/src/metaprog.c
+++ b/mrbgems/mruby-metaprog/src/metaprog.c
@@ -1,13 +1,13 @@
-#include "mruby.h"
-#include "mruby/array.h"
-#include "mruby/hash.h"
-#include "mruby/variable.h"
-#include "mruby/proc.h"
-#include "mruby/class.h"
-#include "mruby/string.h"
+#include <mruby.h>
+#include <mruby/array.h>
+#include <mruby/hash.h>
+#include <mruby/variable.h>
+#include <mruby/proc.h>
+#include <mruby/class.h>
+#include <mruby/string.h>
 #include <mruby/internal.h>
-#include "mruby/khash.h"
-#include "mruby/presym.h"
+#include <mruby/khash.h>
+#include <mruby/presym.h>
 
 typedef enum {
   NOEX_PUBLIC    = 0x00,
diff --git a/mrbgems/mruby-method/src/method.c b/mrbgems/mruby-method/src/method.c
index f12cc44b6..1ec689432 100644
--- a/mrbgems/mruby-method/src/method.c
+++ b/mrbgems/mruby-method/src/method.c
@@ -1,11 +1,11 @@
-#include "mruby.h"
-#include "mruby/array.h"
-#include "mruby/class.h"
-#include "mruby/variable.h"
-#include "mruby/proc.h"
-#include "mruby/string.h"
-#include "mruby/internal.h"
-#include "mruby/presym.h"
+#include <mruby.h>
+#include <mruby/array.h>
+#include <mruby/class.h>
+#include <mruby/variable.h>
+#include <mruby/proc.h>
+#include <mruby/string.h>
+#include <mruby/internal.h>
+#include <mruby/presym.h>
 
 // Defined by mruby-proc-ext on which mruby-method depends
 mrb_value mrb_proc_parameters(mrb_state *mrb, mrb_value proc);
diff --git a/mrbgems/mruby-pack/src/pack.c b/mrbgems/mruby-pack/src/pack.c
index 8f61b0bb7..aa312c0e7 100644
--- a/mrbgems/mruby-pack/src/pack.c
+++ b/mrbgems/mruby-pack/src/pack.c
@@ -3,13 +3,13 @@
  */
 
 #include <mruby.h>
-#include "mruby/error.h"
-#include "mruby/array.h"
-#include "mruby/class.h"
-#include "mruby/numeric.h"
-#include "mruby/string.h"
-#include "mruby/variable.h"
-#include "mruby/endian.h"
+#include <mruby/error.h>
+#include <mruby/array.h>
+#include <mruby/class.h>
+#include <mruby/numeric.h>
+#include <mruby/string.h>
+#include <mruby/variable.h>
+#include <mruby/endian.h>
 
 #include <ctype.h>
 #include <string.h>
diff --git a/mrbgems/mruby-sleep/src/sleep.c b/mrbgems/mruby-sleep/src/sleep.c
index 4b30ceaea..5a63d4293 100644
--- a/mrbgems/mruby-sleep/src/sleep.c
+++ b/mrbgems/mruby-sleep/src/sleep.c
@@ -36,7 +36,7 @@
     #include <sys/time.h>
 #endif
 
-#include "mruby.h"
+#include <mruby.h>
 
 /* not implemented forever sleep (called without an argument)*/
 static mrb_value
diff --git a/mrbgems/mruby-socket/src/socket.c b/mrbgems/mruby-socket/src/socket.c
index 73d89e6c3..16fe78f9b 100644
--- a/mrbgems/mruby-socket/src/socket.c
+++ b/mrbgems/mruby-socket/src/socket.c
@@ -30,18 +30,18 @@
 
 #include <string.h>
 
-#include "mruby.h"
-#include "mruby/array.h"
-#include "mruby/class.h"
-#include "mruby/data.h"
-#include "mruby/numeric.h"
-#include "mruby/string.h"
-#include "mruby/variable.h"
-#include "mruby/error.h"
-#include "mruby/internal.h"
-#include "mruby/presym.h"
+#include <mruby.h>
+#include <mruby/array.h>
+#include <mruby/class.h>
+#include <mruby/data.h>
+#include <mruby/numeric.h>
+#include <mruby/string.h>
+#include <mruby/variable.h>
+#include <mruby/error.h>
+#include <mruby/internal.h>
+#include <mruby/presym.h>
 
-#include "mruby/ext/io.h"
+#include <mruby/ext/io.h>
 
 #if !defined(HAVE_SA_LEN)
 #if (defined(BSD) && (BSD >= 199006))
diff --git a/mrbgems/mruby-socket/test/sockettest.c b/mrbgems/mruby-socket/test/sockettest.c
index 02eb1e1a8..790351702 100644
--- a/mrbgems/mruby-socket/test/sockettest.c
+++ b/mrbgems/mruby-socket/test/sockettest.c
@@ -1,7 +1,7 @@
 #include <stdlib.h>
 
-#include "mruby.h"
-#include "mruby/error.h"
+#include <mruby.h>
+#include <mruby/error.h>
 
 #if defined(_WIN32) || defined(_WIN64)
 
diff --git a/mrbgems/mruby-time/include/mruby/time.h b/mrbgems/mruby-time/include/mruby/time.h
index 1adcfd49c..9149e0af2 100644
--- a/mrbgems/mruby-time/include/mruby/time.h
+++ b/mrbgems/mruby-time/include/mruby/time.h
@@ -7,7 +7,7 @@
 #ifndef MRUBY_TIME_H
 #define MRUBY_TIME_H
 
-#include "mruby/common.h"
+#include <mruby/common.h>
 #include <time.h>
 
 MRB_BEGIN_DECL
diff --git a/mruby-source.gemspec b/mruby-source.gemspec
index 6dff87e87..ee284474c 100644
--- a/mruby-source.gemspec
+++ b/mruby-source.gemspec
@@ -5,7 +5,7 @@ require 'mruby/source'
 Gem::Specification.new do |spec|
   spec.name          = "mruby-source"
   spec.version       = MRuby::Source::MRUBY_VERSION
-  spec.authors       = [ MRuby::Source::MRUBY_AUTHOR ]
+  spec.authors       = [ "mruby developers" ]
 
   spec.summary       = %q{mruby source code wrapper.}
   spec.description   = %q{mruby source code wrapper for use with Ruby libs.}
diff --git a/src/allocf.c b/src/allocf.c
index aa9ca646f..b5c7d4b03 100644
--- a/src/allocf.c
+++ b/src/allocf.c
@@ -3,9 +3,8 @@
 **
 ** See Copyright Notice in mruby.h
 */
-
 #include <stdlib.h>
-#include "mruby.h"
+#include <mruby.h>
 
 /* This function serves as the default memory allocation function and accepts four arguments:
  *
diff --git a/src/codedump.c b/src/codedump.c
index 292527f27..288a196db 100644
--- a/src/codedump.c
+++ b/src/codedump.c
@@ -581,7 +581,7 @@ codedump(mrb_state *mrb, const mrb_irep *irep, FILE *out)
       ins = READ_B();
       switch (ins) {
 #define OPCODE(i,x) case OP_ ## i: FETCH_ ## x ## _1 (); goto L_OP_ ## i;
-#include "mruby/ops.h"
+#include <mruby/ops.h>
 #undef OPCODE
       }
       break;
@@ -591,7 +591,7 @@ codedump(mrb_state *mrb, const mrb_irep *irep, FILE *out)
       ins = READ_B();
       switch (ins) {
 #define OPCODE(i,x) case OP_ ## i: FETCH_ ## x ## _2 (); goto L_OP_ ## i;
-#include "mruby/ops.h"
+#include <mruby/ops.h>
 #undef OPCODE
       }
       break;
@@ -601,7 +601,7 @@ codedump(mrb_state *mrb, const mrb_irep *irep, FILE *out)
       ins = READ_B();
       switch (ins) {
 #define OPCODE(i,x) case OP_ ## i: FETCH_ ## x ## _3 (); goto L_OP_ ## i;
-#include "mruby/ops.h"
+#include <mruby/ops.h>
 #undef OPCODE
       }
       break;
diff --git a/src/vm.c b/src/vm.c
index 45f2a208f..ae0738141 100644
--- a/src/vm.c
+++ b/src/vm.c
@@ -1387,7 +1387,7 @@ mrb_vm_exec(mrb_state *mrb, const struct RProc *proc, const mrb_code *pc)
 #ifndef MRB_USE_VM_SWITCH_DISPATCH
   static const void * const optable[] = {
 #define OPCODE(x,_) &&L_OP_ ## x,
-#include "mruby/ops.h"
+#include <mruby/ops.h>
 #undef OPCODE
   };
 #endif
@@ -3039,7 +3039,7 @@ RETRY_TRY_BLOCK:
       insn = READ_B();
       switch (insn) {
 #define OPCODE(insn,ops) case OP_ ## insn: FETCH_ ## ops ## _1(); mrb->c->ci->pc = pc; goto L_OP_ ## insn ## _BODY;
-#include "mruby/ops.h"
+#include <mruby/ops.h>
 #undef OPCODE
       }
       pc--;
@@ -3049,7 +3049,7 @@ RETRY_TRY_BLOCK:
       insn = READ_B();
       switch (insn) {
 #define OPCODE(insn,ops) case OP_ ## insn: FETCH_ ## ops ## _2(); mrb->c->ci->pc = pc; goto L_OP_ ## insn ## _BODY;
-#include "mruby/ops.h"
+#include <mruby/ops.h>
 #undef OPCODE
       }
       pc--;
@@ -3059,7 +3059,7 @@ RETRY_TRY_BLOCK:
       insn = READ_B();
       switch (insn) {
 #define OPCODE(insn,ops) case OP_ ## insn: FETCH_ ## ops ## _3(); mrb->c->ci->pc = pc; goto L_OP_ ## insn ## _BODY;
-#include "mruby/ops.h"
+#include <mruby/ops.h>
 #undef OPCODE
       }
       pc--;