Beer and friends from tomorrow evening at the London Perl Workshop

How exciting! The London Perl Workshop is this Saturday, and as you may or may not know, it's not just London's premier Perl event, it's also London's premier social event! It's not to late to register to attend, for free!

Pre-Workshop Drinks

wcn.pngOur generous sponsor WCN are sponsoring a pre-workshop social event, which is a chance to catch up with old friends, make new friends, and hang out drinking beer (or wine, or whatever you want really) around Perl-y people. WCN specialise in providing a cloud-based talent acquisition technology suite and have decades of award-winning recruitment software expertise and an obsession with driving real change in organisations.

The pre-workshop drinks are at the Carpenter's Arms:

From 6:30pm on Friday the 24th

Post-Workshop Drinks

Perl5 as a first-class script engine in Java

Perlito5 is an implementation of the Perl5 language that runs in the Java / JVM platform.

Perl scripts can now be run from inside Java applications using the standard javax.script API:

// $ javac -cp .:perlito5.jar
// $ java -cp .:perlito5.jar Script

import javax.script.*;

public class Script {
    public static void main(String[] args) throws Exception {

        ScriptEngineManager factory = new ScriptEngineManager();
        ScriptEngine engine = factory.getEngineByName("Perl5");

        Object o = engine.eval(" $x = 456; say 123 + $x; \"value was $x\" ");
        System.out.println("result: " + o);

Perl modules can be loaded after setting @INC.

About 40 core modules have been ported to this distribution, and it passes about 23,000 tests.

PullRequest - Personal Milestone

On 16th Aug 2017, the CPAN day, I blogged about my plan for the day. In that blog, I also mentioned about my personal milestone, finishing maximum number of months in a calendar year with atleast one PR each day. If I look back historical data, in the year 2015, I had 3 such months (Oct:45, Nov:31, Dec:60).

The following year 2016, doesn't look nice, as I could only get in 1 month (Dec: 77).

However, the year 2017, looks much better as compare to previous two years. So far I managed to get in 5 months with at least 1 PR each day ((Jan:63, Jul:32, Aug:42, Oct:40, Nov: 30).

I am hoping to get Dec in as well to make it 6 months in the year 2017 beating my previous best 3 months in the year (2015). The chances are very bright as I will be participating the 24PullRequest challenge next month, which runs from 1st Dec - 24th Dec.

Overall, so far, as of today, I have submitted 605 PullRequests out of those 400 have been accepted and merged.

Perl 5 Porters Mailing List Summary: November 13th-20th

Hey everyone,

Following is the p5p (Perl 5 Porters) mailing list summary for the past week.


grep.metacpan @meta::hack 2017

The MetaCPAN 2017 Hackathon, a.k.a. meta::hack v2, is the second dedicated MetaCPAN hackathon. This year the event was held in Chicago from November 16th to 19th, in server central office.

I would like to give special thanks to all event sponsors:, cPanel, ServerCentral, Kritika without them this would have not been possible.

I took part in this event during the last three days and mainly focused on project, which was created as an experimental project earlier this year during the QA Hackathon in Lyon, France.

That article is just a quick summary of my current participation, much more happened from all other participants, and global progress made is pretty impressive!

Since the original version of, which appeared broken from Day 1 due to the lack of libpcre support from the git version used, many things improved and I hope you could have a smoother experience searching code extract...

First two minor updates on

Meta::Hack 2

Meta::Hack 2 - 2017


Meta::Hack is about getting the core MetaCPAN team together for a few days to work on improving... well as much as possible! Last year we focused on deploying to a new infrastructure, with new version of Elasticsearch. This year was a much more varied set of things we wanted to achieve.

Why get together?

Whilst Olaf couldn't attend in person, we had him up on the big screen in the ServerCentral (who kindly hosted us and bought us lunch) offices so it was almost as good as him being physically there. Having us together meant we could really support each other as questions arose.. a fun one was tracking down that the string JSON::PP::Boolean, incorrectly identifies as is_bool in JSON::PP - there is a pull request - though that's not released yet. We also found bugs in our own code!



What are you doing on 25th Nov 2017?

Why am I asking this? If you are not aware then I must tell you the much awaited London Perl Workshop is happening next Saturday, 25th Nov 2017. I am looking forward to the event. There are plenty of interesting talks arranged this time. Take a look at the list of talks. If you are planning to attend any particular talk, please register your interest as well. This will help the organiser in scheduling it.

There is one more reason I am excited about the event. I am giving my second talk at London Perl Workshop this year. I feel humbled to see so many people showing interest in my talk. The topic of my talk is "Create tube map in 20 minutes using Map::Tube". I will be taking the audience through various steps in creating a tube map. I promise at the end of talk, everyone in audience would be able create their own little map in no time.

graphql-perl - plugin to make GraphQL "just work" with DBIx::Class

As mentioned in the LPW "trailer" for shiny new toys, I will be giving a talk on graphql-perl. I promised to talk about introspecting a DBIx::Class schema to make a GraphQL interface. This is how!

The API for a "convert plugin" for graphql-perl is simple: implement a to_graphql, and optionally a from_graphql method. The to_graphql returns a hash-ref with three keys:

  • schema
  • root_value
  • resolver

These are all the entities, apart from the specifics of an individual query/request, needed for GraphQL's execute to operate. The Mojolicious and Dancer2 plugins need only to be given which plugin to call, and any necessary arguments (e.g. a DBIx::Class::Schema object) and they can now create a GraphQL endpoint from that.

The newly-released v0.03 of GraphQL::Plugin::Convert::DBIC is the first functioning plugin. It implements generic CRUD for the given DBIC schema: it creates two types of Read (primary key, and "search" on fields), and Create, Update and Delete mutations.

Perl and AI

Following a brain fart, I've had a dig around for AI related stuff in perl. I haven't found much currently active, except an interface library for an Apache project (which looks good). I've found very little in the sentiment analysis sphere. This is what I've found so far:

AI::Categorizer Not touched since 2007
AI::NeuralNet::Simple Not touched since 2005
AI::FANN Not touched since 2009 Old!
AI::NeuralNet::BackProp Not touched since 2000
AI::Perceptron Not touched since 2003

And the live one:

AI::MXNet Live!
Interfaces to

Am I missing anything obvious?

Perl and the Operating System at the London Perl Workshop, 25th of November

One of the strengths of both Perl -- and our talk schedule -- is a diversity of ideas. We see this in the rich depth of Perl libraries on the CPAN, in the large variety of places Perl is deployed, and in the many ways people use Perl to make their lives easier.

eligo.pngThis summary is brought to you by our Platinum Sponsor: Eligo. Eligo are a niche recruitment agency with a team of dedicated Perl Consultants, who specialise in and have experience in recruiting Perl Specialists across a wide range of sectors and roles in the UK and beyond.

Perl and the Operating System

Lacey Powers -- better known as Perl's resident Postgres badass -- gives us a tour of "Debian Tips and Tricks", showing us that Debian is a fantastic platform for running your applications, Perl or otherwise, on. The talk will cover some of her favorite tips and tricks to make your life using and administering Debian easier. Debian goodies, unattended upgrades, molly guard, useful non-Debian project repositories, and many others will be covered.

Perl 5 Porters Mailing List Summary: November 2nd-12th

Hey everyone,

Following is the p5p (Perl 5 Porters) mailing list summary for the past week and a half.


Human Perl at the London Perl Workshop November 25th

There's more to Perl than perl. There are Perl people, there's a smattering of Perl philosophy, and there are many other peculiarities on the Perl periphery. This year's London Perl Workshop will have some great talks on Perl-y subjects that don't just focus on the language itself!

adzuna.pngThis summary is brought to you by one of our sponsors: Adzuna, a search engine for job ads used by over 7 million visitors per month that aims to list every job, everywhere, proudly built in Perl.

Human Perl

Julien Fiegehenn (‎simbabque‎) will tell us how he "[Turns] humans into developers with Perl" -- his methodology for teaching apprentice software developers. He often works with young trainees who start their professional careers with very little to no prior tech knowledge and will cover the social aspects of being a mentor and show process examples that help with long-term motivation.

Perl client for NATS Streaming Messaging System

Hello all,

With micro-services and cloud being a buzzwords of the day it's no surprise that a market for messaging systems is pretty busy at the moment.

One such system (NATS and persistent version NATS Streaming) seems to be a leader among relatively new arrivals. If interested please read more on it at its official page

There's a lot of clients for original NATS already exist on the market, including one for Perl,
Net::NATS::Client, though without support for recently added NATS Streaming. I did not think that was optimal and wrote one.

The purpose of this blog post is the announcement of new Perl Client for NATS streaming I just uploaded to CPAN and github Net::NATS::Streaming::Client.

From the README.

Net::NATS::Streaming::Client - A Perl client 
for the NATS Streaming messaging system.

Basic Usage
This class is a subclass of Net::NATS::Client 
and delegates all networking to the parent.

use Net::NATS::Streaming::Client;
$client = Net::NATS::Streaming::Client->new(
  uri => 'nats://localhost:4222'

$client->connect() or die $!;

$subscription = $client->subscribe_channel(
  { subject => 'foo' }, sub { warn shift->data } 
  { subject => 'foo', data => 'Hello, World!'}



Hopefully it'll be useful for Perl community.

I want my, I want my Kwa-li-tee

If you publish code to CPAN, you've probably noticed the steady improvement in its entire ecosystem over the last couple of years. ++Neil Bowers and ++the meta::cpan core hackers in particular have laboured tirelessly to improve the release process for authors and the user experience for consumers of CPAN code.

One of the things that's most useful as an author is the CPANTS Kwalitee ratings generated for any release to CPAN. The Kwalitee ranking markers are continuously being improved and added to, and I recently updated my build config to follow some recommendations the system gave me.

I use Dist::Zilla for publishing to CPAN, and I was able to address all the recommendations using Dist::Zilla plugins. Here are the newly added configs in my dist.ini:

perl hacking

I am now going to talk about my perl 5 code repository, it is located at

There is a module HollyGame which is about the fastest game kit for adventures/RPGs and so on by using everything in lists, e.g. enemies, sprites lists which are updated every game loop and a image resource indexer which gets you the next image also from a list of images. It was primarily developed on FreeBSD, which is why they didn't include it in CPAN.

If you like Linux more then there is a HollyGameRPGAI which uses a Gauss formula of the Gauss Support Vector Machine to wander around enemies or other non-player characters.

To show the "power" of HollyGame there are examples in that same directory which use it with an SDL 1.2 layer (SDL on CPAN), there is also a Wycadia and Ultima 8 perl game start which I am further working on. The Ultima 8 program has a system for walking around in low levels of platforms inside the file. Each hashed level contains intersected objects with that width, height and depth instead of a usual octtree using contained items.


The Great London Perl Bake Off

You may not have noticed, but the London Perl Workshop is happening later this month (Saturday 25th November). It's a free-to-attend community event: organised by members of the community, for the community, and made possible by sponsorship from companies in our community.

Reinforcing the community theme, we're trying an experiment this year: crowd-sourcing bakes from attendees for one of the coffee breaks. If you're an experienced baker, an occasional dabbler (like myself), or even a complete neophyte looking for a reason to start, why not give it a go?

London.PM at a glance

Shiny New Toys at the London Perl Workshop, Nov 25th

Who doesn't like shiny things? I love shiny things. The London Perl Workshop loves shiny things. CV-Library, this post's sponsor, loves shiny things. So if you come to the London Perl Workshop, Nov 25th, you'll learn about some shiny things.

Shiny Things!

cvl.pngThis summary is brought to you by one of our sponsors: CV-Library. CV-Library is the UK's leading independent job board, developed in Perl and is hiring developers in its London and Fleet offices. CV-Library's technical director is also one of this year's organisers!

Shiny New Toys

The inimitable Ed J (‎mohawk‎) will be talking about his sterling progress in developing "GraphQL in Perl: The Story So Far". GraphQL is the Next Big Thing in implementing APIs, maybe even a successor to REST. Ed has ported the JavaScript reference implementation to Perl, plus written plugins for Dancer 2 and Mojolicious to make it trivial to add a GraphQL endpoint to your web application. He'll also talking about exposing DBIx::Class schemas -- and, more generally, Moose classes -- via GraphQL using introspection.

Inline::F2003 - An ILSM for modern FORTRAN

I would like to announce the first release of Inline::F2003. The project features the program "", which performs a matrix multiplication calculation, to showcase the use of Inline::F2003.

The project's URL is:

Inline::F2003 is a Perl extension module that allows program units written in modern FORTRAN to be added into the "__DATA__" section of a Perl program. The term "program units" is a collective FORTRAN term that refers to subroutines, functions, and module procedures. The module reads the FORTRAN source code, compiles it into object files, and builds a single shared library file.

What Time is Midnight?

Yesterday was time change in the U. S. of A. I pulled out my iPod Touch to update a Numbers spreadsheet, and hit the "today" button to put the current date in the date column. But when I did that I got not the current date but 11 PM the previous day. Today it works as advertised.

Now, I am not privy to the internals here, but this behavior would be explained if "today" were implemented by the Objective C (or Swift, or whatever) equivalent of the following Perl:

my $date = time + $zone_offset;
$date -= $date % 86400;

This code is clean, simple, obvious ... and subtly wrong because on time change day, after the change, midnight has a different offset than the current time. This is a bug that manifests only 44 hours in every year. I think that when I want the local day I round-trip through localtime and Time::Local::timelocal. But do I really? Always? And would the above snippet be valid for UTC?

I just did ack '%\s*86000\b' on my Perl modules, and came up dry. Then I looked for '=>\s*86000;' to find relevant manifest constants (three -- I'm considering picking a name and converging all modules to it), and find the modulo operations on them. Still nothing. Am I really clean? What about you?

About is a common blogging platform for the Perl community. Written in Perl and offering the modern features you’ve come to expect in blog platforms, the site is hosted by Dave Cross and Aaron Crane, with a design donated by Six Apart, Ltd.