diff --git a/.gitignore b/.gitignore
index ebb7396..804a748 100644
--- a/.gitignore
+++ b/.gitignore
@@ -48,3 +48,4 @@
 /MCE-1.836.tar.gz
 /MCE-1.837.tar.gz
 /MCE-1.838.tar.gz
+/MCE-1.840.tar.gz
diff --git a/MCE-1.834-Sereal-deps.patch b/MCE-1.840-Sereal-deps.patch
similarity index 52%
rename from MCE-1.834-Sereal-deps.patch
rename to MCE-1.840-Sereal-deps.patch
index 3409068..cd9ad59 100644
--- a/MCE-1.834-Sereal-deps.patch
+++ b/MCE-1.840-Sereal-deps.patch
@@ -1,5 +1,20 @@
 Upstream's syntax is mis-parsed by the rpm dependency generator as a hard requirement.
 
+--- lib/MCE/Channel.pm
++++ lib/MCE/Channel.pm
+@@ -27,10 +27,8 @@ my ( $freeze, $thaw );
+ 
+ BEGIN {
+    if ( ! defined $INC{'PDL.pm'} ) {
+-      local $@; eval '
+-         use Sereal::Encoder 3.015 qw( encode_sereal );
+-         use Sereal::Decoder 3.015 qw( decode_sereal );
+-      ';
++      local $@;
++      eval 'use Sereal::Encoder 3.015 qw( encode_sereal ); use Sereal::Decoder 3.015 qw( decode_sereal );';
+       if ( ! $@ ) {
+          my $encoder_ver = int( Sereal::Encoder->VERSION() );
+          my $decoder_ver = int( Sereal::Decoder->VERSION() );
 --- lib/MCE.pm
 +++ lib/MCE.pm
 @@ -36,10 +36,7 @@ BEGIN {
diff --git a/perl-MCE.spec b/perl-MCE.spec
index 4c91f59..1050cdf 100644
--- a/perl-MCE.spec
+++ b/perl-MCE.spec
@@ -1,12 +1,12 @@
 Name:           perl-MCE
-Version:        1.838
-Release:        3%{?dist}
+Version:        1.840
+Release:        1%{?dist}
 Summary:        Many-core Engine for Perl providing parallel processing capabilities
 License:        GPL+ or Artistic
 URL:            https://metacpan.org/release/MCE
 Source0:        https://cpan.metacpan.org/authors/id/M/MA/MARIOROY/MCE-%{version}.tar.gz
 Patch0:         MCE-1.818-Fix-sharp-bang-line.patch
-Patch1:         MCE-1.834-Sereal-deps.patch
+Patch1:         MCE-1.840-Sereal-deps.patch
 BuildArch:      noarch
 # Module Build
 BuildRequires:  coreutils
@@ -24,13 +24,17 @@ BuildRequires:  perl(Errno)
 BuildRequires:  perl(Exporter)
 BuildRequires:  perl(Fcntl)
 BuildRequires:  perl(File::Path)
+BuildRequires:  perl(if)
 BuildRequires:  perl(IO::Handle)
+BuildRequires:  perl(overload)
+BuildRequires:  perl(POSIX)
 BuildRequires:  perl(Scalar::Util)
 BuildRequires:  perl(Sereal) >= 3.015
 BuildRequires:  perl(Socket)
 BuildRequires:  perl(Storable) >= 2.04
 BuildRequires:  perl(strict)
 BuildRequires:  perl(Symbol)
+BuildRequires:  perl(threads)
 BuildRequires:  perl(threads::shared)
 BuildRequires:  perl(Time::HiRes)
 BuildRequires:  perl(warnings)
@@ -44,6 +48,7 @@ BuildRequires:  perl(Test::More) >= 0.88
 # Dependencies
 Requires:       perl(:MODULE_COMPAT_%(eval "$(perl -V:version)"; echo $version))
 Requires:       perl(File::Path)
+Requires:       perl(POSIX)
 Requires:       perl(Sereal) >= 3.015
 Requires:       perl(Storable) >= 2.04
 Requires:       perl(Symbol)
@@ -108,6 +113,9 @@ make test
 %dir %{perl_vendorlib}/MCE/Core/
 %{perl_vendorlib}/MCE.pm
 %{perl_vendorlib}/MCE/Candy.pm
+%{perl_vendorlib}/MCE/Channel/
+%{perl_vendorlib}/MCE/Channel.pm
+%{perl_vendorlib}/MCE/Child.pm
 %{perl_vendorlib}/MCE/Core/Input/
 %{perl_vendorlib}/MCE/Core/Manager.pm
 %{perl_vendorlib}/MCE/Core/Validation.pm
@@ -127,6 +135,11 @@ make test
 %{perl_vendorlib}/MCE/Util.pm
 %{_mandir}/man3/MCE.3*
 %{_mandir}/man3/MCE::Candy.3*
+%{_mandir}/man3/MCE::Channel.3*
+%{_mandir}/man3/MCE::Channel::Mutex.3*
+%{_mandir}/man3/MCE::Channel::Simple.3*
+%{_mandir}/man3/MCE::Channel::Threads.3*
+%{_mandir}/man3/MCE::Child.3*
 %{_mandir}/man3/MCE::Core.3*
 %{_mandir}/man3/MCE::Examples.3*
 %{_mandir}/man3/MCE::Flow.3*
@@ -135,6 +148,7 @@ make test
 %{_mandir}/man3/MCE::Map.3*
 %{_mandir}/man3/MCE::Mutex.3*
 %{_mandir}/man3/MCE::Mutex::Channel.3*
+%{_mandir}/man3/MCE::Mutex::Channel2.3*
 %{_mandir}/man3/MCE::Mutex::Flock.3*
 %{_mandir}/man3/MCE::Queue.3*
 %{_mandir}/man3/MCE::Relay.3*
@@ -153,6 +167,30 @@ make test
 %{_bindir}/mce_zfgrep
 
 %changelog
+* Sun Jul  7 2019 Paul Howarth <paul@city-fan.org> - 1.840-1
+- Update to 1.840
+  New Features
+  - Added MCE::Mutex::Channel2 providing two locks using a single channel; the
+    secondary lock is accessible by calling methods with the '2' suffix, e.g.
+    primary mutex ->lock, ->unlock; secondary mutex ->lock2, ->unlock2
+  - Added MCE::Channel providing queue-like and two-way communication
+    supporting threads and processes
+  - Added MCE::Child and compatibility with Perl 5.8; MCE::Child is based on
+    MCE::Hobo, but using MCE::Channel for data retrieval without involving a
+    shared-manager process
+  - Added MCE::Channel examples { channel1.pl and channel2.pl } using threads
+    and MCE::Child respectively
+  Enhancements
+  - IPC update; removed unnecessary overhead including private methods _sysseek
+    and _syswrite from MCE::Util (no longer needed)
+  - Improved MCE->do, now callable by workers and the manager process
+  - Updated MCE::{ Flow, Grep, Loop, Map, Step, and Stream } documentation on
+    passing an array reference versus a list for deeply input data
+  - Updated and re-organized the top-level MCE documentation, particularly
+    improved clarity for the 'MCE Models' section
+  - Removed MANIFEST.SKIP
+  - Update MCE::Channel POD documentation
+
 * Fri May 31 2019 Jitka Plesnikova <jplesnik@redhat.com> - 1.838-3
 - Perl 5.30 rebuild
 
diff --git a/sources b/sources
index bb070ea..fcdec40 100644
--- a/sources
+++ b/sources
@@ -1 +1 @@
-SHA512 (MCE-1.838.tar.gz) = 33db263a5b8b8eea73dbec2fff9dc0c92fbd075215f0c6a9e21621530cb7f93a23939a02211fe0481c8ba22c2d470437e716f6d2328b7b568cb1bd17b280dc65
+SHA512 (MCE-1.840.tar.gz) = d4738cff0ef85b1d491eb6f3ff4dd7cdb3bc3dc7fd9442d574ea6938e5c613c1d376fcb6a2448becb2d942409286209224a10ee886726b9d747f7f4897f83572