diff --git a/.gitignore b/.gitignore
index 1c18cc1a966..e8d105c92d8 100644
--- a/.gitignore
+++ b/.gitignore
@@ -35,6 +35,7 @@ compile_commands.json
 
 autom4te.cache
 configure
+configure~
 config.log
 config.status
 Makefile
diff --git a/configure.ac b/configure.ac
index b0fea405da1..612e6b544fa 100644
--- a/configure.ac
+++ b/configure.ac
@@ -1,7 +1,11 @@
-AC_INIT
+AC_INIT(YARP, 0.5.0, https://github.com/ruby/yarp/issues/new, yarp, https://github.com/ruby/yarp)
 AC_PROG_CC
 AC_DEFINE(_XOPEN_SOURCE, 700)
 AC_CHECK_FUNCS(mmap)
 AC_CHECK_FUNCS(strncasecmp)
 AC_CONFIG_FILES([Makefile])
 AC_OUTPUT
+
+# Copy over the confdefs.h to build so other tools can use it.
+mkdir -p build
+cp confdefs.h build/confdefs.h
diff --git a/ext/yarp/extension.h b/ext/yarp/extension.h
index e573be61714..2110247325f 100644
--- a/ext/yarp/extension.h
+++ b/ext/yarp/extension.h
@@ -15,7 +15,7 @@
 #include <unistd.h>
 #endif
 
-#define EXPECTED_YARP_VERSION "0.4.0"
+#define EXPECTED_YARP_VERSION "0.5.0"
 
 VALUE yp_token_new(yp_parser_t *parser, yp_token_t *token, rb_encoding *encoding);
 
diff --git a/include/yarp.h b/include/yarp.h
index 3c43876f9d4..bc41815b37b 100644
--- a/include/yarp.h
+++ b/include/yarp.h
@@ -27,7 +27,7 @@
 #include "yarp/util/yp_strpbrk.h"
 
 #define YP_VERSION_MAJOR 0
-#define YP_VERSION_MINOR 4
+#define YP_VERSION_MINOR 5
 #define YP_VERSION_PATCH 0
 
 void yp_serialize_content(yp_parser_t *parser, yp_node_t *node, yp_buffer_t *buffer);
diff --git a/templates/java/org/yarp/Loader.java.erb b/templates/java/org/yarp/Loader.java.erb
index e0bbbdfc4be..5cedbfe9cec 100644
--- a/templates/java/org/yarp/Loader.java.erb
+++ b/templates/java/org/yarp/Loader.java.erb
@@ -54,7 +54,7 @@ public class Loader {
         expect((byte) 'P');
 
         expect((byte) 0);
-        expect((byte) 4);
+        expect((byte) 5);
         expect((byte) 0);
 
         // This loads the name of the encoding. We don't actually do anything
diff --git a/templates/lib/yarp/serialize.rb.erb b/templates/lib/yarp/serialize.rb.erb
index 96150c1e6b2..aad6f167517 100644
--- a/templates/lib/yarp/serialize.rb.erb
+++ b/templates/lib/yarp/serialize.rb.erb
@@ -26,7 +26,7 @@ module YARP
 
       def load
         io.read(4) => "YARP"
-        io.read(3).unpack("C3") => [0, 4, 0]
+        io.read(3).unpack("C3") => [0, 5, 0]
 
         @encoding = Encoding.find(io.read(load_varint))
         @source = source.force_encoding(@encoding).freeze