diff --git a/.appveyor.yml b/.appveyor.yml
index ea4de63..a475b5e 100644
--- a/.appveyor.yml
+++ b/.appveyor.yml
@@ -4,7 +4,7 @@
 #         GENERATED SOURCE CODE, DO NOT EDIT EXCEPT EXPERIMENTALLY
 #
 ###############################################################################
-version: 3.4.0.{build}-{branch}
+version: 3.6.0.{build}-{branch}
 
 image: Visual Studio 2013
 
diff --git a/.travis.yml b/.travis.yml
index ac786aa..e885056 100644
--- a/.travis.yml
+++ b/.travis.yml
@@ -35,7 +35,7 @@ matrix:
               sources:
                 - sourceline: 'ppa:h-rayflood/llvm'
               packages:
-                - clang-3.4
+                - clang-5.0
         - os: linux
           compiler: gcc
           env: LINK=dynamic
@@ -66,7 +66,7 @@ install:
 
     # Export CC/CXX to control compiler/version.
     - if [[ $OSX   && $CLANG && $STATIC  ]]; then export CC=clang; export CXX=clang++; fi
-    - if [[ $LINUX && $CLANG && $STATIC  ]]; then export CC=clang-3.4; export CXX=clang++-3.4; fi
+    - if [[ $LINUX && $CLANG && $STATIC  ]]; then export CC=clang-5.0; export CXX=clang++-5.0; fi
     - if [[ $LINUX && $GCC   && $STATIC  ]]; then export CC=gcc; export CXX=g++; fi
     - if [[ $OSX   && $CLANG && $DYNAMIC ]]; then export CC=clang; export CXX=clang++; fi
     - if [[ $LINUX && $CLANG && $DYNAMIC ]]; then export CC=clang; export CXX=clang++; fi
diff --git a/configure.ac b/configure.ac
index 6ba1774..572adaf 100644
--- a/configure.ac
+++ b/configure.ac
@@ -13,7 +13,7 @@
 AC_PREREQ([2.65])
 
 # Process command-line arguments and perform initialization and verification.
-AC_INIT([libbitcoin-client], [3.4.0], [eric@voskuil.org])
+AC_INIT([libbitcoin-client], [3.6.0], [eric@voskuil.org])
 
 # Do compilation tests.
 AC_LANG(C++)
@@ -157,14 +157,14 @@ AS_CASE([${with_tests}], [yes],
      AC_MSG_NOTICE([boost_unit_test_framework_LIBS : ${boost_unit_test_framework_LIBS}])],
     [AC_SUBST([boost_unit_test_framework_LIBS], [])])
 
-# Require bitcoin of at least version 3.4.0 and output ${bitcoin_CPPFLAGS/LIBS/PKG}.
+# Require bitcoin of at least version 3.6.0 and output ${bitcoin_CPPFLAGS/LIBS/PKG}.
 #------------------------------------------------------------------------------
-PKG_CHECK_MODULES([bitcoin], [libbitcoin >= 3.4.0],
-    [bitcoin_INCLUDEDIR="`$PKG_CONFIG --variable=includedir "libbitcoin >= 3.4.0" 2>/dev/null`"
-     bitcoin_OTHER_CFLAGS="`$PKG_CONFIG --cflags-only-other "libbitcoin >= 3.4.0" 2>/dev/null`"],
+PKG_CHECK_MODULES([bitcoin], [libbitcoin >= 3.6.0],
+    [bitcoin_INCLUDEDIR="`$PKG_CONFIG --variable=includedir "libbitcoin >= 3.6.0" 2>/dev/null`"
+     bitcoin_OTHER_CFLAGS="`$PKG_CONFIG --cflags-only-other "libbitcoin >= 3.6.0" 2>/dev/null`"],
     [bitcoin_INCLUDEDIR=""
      bitcoin_OTHER_CFLAGS=""])
-AC_SUBST([bitcoin_PKG], ['libbitcoin >= 3.4.0'])
+AC_SUBST([bitcoin_PKG], ['libbitcoin >= 3.6.0'])
 AC_SUBST([bitcoin_CPPFLAGS], [${bitcoin_CFLAGS}])
 AS_IF([test x${bitcoin_INCLUDEDIR} != "x"],
     [AC_SUBST([bitcoin_ISYS_CPPFLAGS], ["-isystem${bitcoin_INCLUDEDIR} ${bitcoin_OTHER_CFLAGS}"])],
@@ -181,14 +181,14 @@ AS_CASE([${enable_isystem}],[yes],
 
 AC_MSG_NOTICE([bitcoin_BUILD_CPPFLAGS : ${bitcoin_BUILD_CPPFLAGS}])
 
-# Require bitcoin-protocol of at least version 3.4.0 and output ${bitcoin_protocol_CPPFLAGS/LIBS/PKG}.
+# Require bitcoin-protocol of at least version 3.6.0 and output ${bitcoin_protocol_CPPFLAGS/LIBS/PKG}.
 #------------------------------------------------------------------------------
-PKG_CHECK_MODULES([bitcoin_protocol], [libbitcoin-protocol >= 3.4.0],
-    [bitcoin_protocol_INCLUDEDIR="`$PKG_CONFIG --variable=includedir "libbitcoin-protocol >= 3.4.0" 2>/dev/null`"
-     bitcoin_protocol_OTHER_CFLAGS="`$PKG_CONFIG --cflags-only-other "libbitcoin-protocol >= 3.4.0" 2>/dev/null`"],
+PKG_CHECK_MODULES([bitcoin_protocol], [libbitcoin-protocol >= 3.6.0],
+    [bitcoin_protocol_INCLUDEDIR="`$PKG_CONFIG --variable=includedir "libbitcoin-protocol >= 3.6.0" 2>/dev/null`"
+     bitcoin_protocol_OTHER_CFLAGS="`$PKG_CONFIG --cflags-only-other "libbitcoin-protocol >= 3.6.0" 2>/dev/null`"],
     [bitcoin_protocol_INCLUDEDIR=""
      bitcoin_protocol_OTHER_CFLAGS=""])
-AC_SUBST([bitcoin_protocol_PKG], ['libbitcoin-protocol >= 3.4.0'])
+AC_SUBST([bitcoin_protocol_PKG], ['libbitcoin-protocol >= 3.6.0'])
 AC_SUBST([bitcoin_protocol_CPPFLAGS], [${bitcoin_protocol_CFLAGS}])
 AS_IF([test x${bitcoin_protocol_INCLUDEDIR} != "x"],
     [AC_SUBST([bitcoin_protocol_ISYS_CPPFLAGS], ["-isystem${bitcoin_protocol_INCLUDEDIR} ${bitcoin_protocol_OTHER_CFLAGS}"])],
diff --git a/include/bitcoin/client/version.hpp b/include/bitcoin/client/version.hpp
index 3ede1ee..06a9906 100644
--- a/include/bitcoin/client/version.hpp
+++ b/include/bitcoin/client/version.hpp
@@ -12,9 +12,9 @@
  * For interpretation of the versioning scheme see: http://semver.org
  */
 
-#define LIBBITCOIN_CLIENT_VERSION "3.4.0"
+#define LIBBITCOIN_CLIENT_VERSION "3.6.0"
 #define LIBBITCOIN_CLIENT_MAJOR_VERSION 3
-#define LIBBITCOIN_CLIENT_MINOR_VERSION 4
+#define LIBBITCOIN_CLIENT_MINOR_VERSION 6
 #define LIBBITCOIN_CLIENT_PATCH_VERSION 0
 
 #endif
diff --git a/install.sh b/install.sh
index 8038364..f9af464 100755
--- a/install.sh
+++ b/install.sh
@@ -34,8 +34,8 @@ BUILD_DIR="build-libbitcoin-client"
 
 # ZMQ archive.
 #------------------------------------------------------------------------------
-ZMQ_URL="https://github.com/zeromq/libzmq/releases/download/v4.2.5/zeromq-4.2.5.tar.gz"
-ZMQ_ARCHIVE="zeromq-4.2.5.tar.gz"
+ZMQ_URL="https://github.com/zeromq/libzmq/releases/download/v4.3.2/zeromq-4.3.2.tar.gz"
+ZMQ_ARCHIVE="zeromq-4.3.2.tar.gz"
 
 # Boost archive.
 #------------------------------------------------------------------------------
@@ -542,7 +542,7 @@ initialize_boost_icu_configuration()
         BOOST_ICU_POSIX="off"
 
         # Extract ICU libs from package config variables and augment with -ldl.
-        ICU_LIBS=( `pkg-config icu-i18n --libs` "-ldl" )
+        ICU_LIBS="`pkg-config icu-i18n --libs` -ldl"
 
         # This is a hack for boost m4 scripts that fail with ICU dependency.
         # See custom edits in ax-boost-locale.m4 and ax_boost_regex.m4.
diff --git a/libbitcoin-client.pc.in b/libbitcoin-client.pc.in
index 9dc3153..142e037 100644
--- a/libbitcoin-client.pc.in
+++ b/libbitcoin-client.pc.in
@@ -25,7 +25,7 @@ Version: @PACKAGE_VERSION@
 #==============================================================================
 # Dependencies that publish package configuration.
 #------------------------------------------------------------------------------
-Requires: libbitcoin >= 3.4.0 libbitcoin-protocol >= 3.4.0
+Requires: libbitcoin >= 3.6.0 libbitcoin-protocol >= 3.6.0
 
 # Include directory and any other required compiler flags.
 #------------------------------------------------------------------------------