blogs.perl.org

For all DevOps enthusiasts, here is a quick introduction to Grafana and Prometheus.
Please check out the link for more information:
https://theweeklychallenge.org/blog/grafana-prometheus

We have 7 high quality and exciting talks, we're looking for many more - as many as we can back into 2 days. Virtual presentations are accepted.

• **Sign up to attend**
• **Submit Talk** (virtual talks permitted!)

Just Paul and Aristotle again.

We discussed the unlimited statement modifier chaining proposal. Both of us thought that unlimited chaining is a bad idea, though we agreed that being able to combine one loop and one conditional would on rare occasions make things slightly nicer. However we also agreed that in terms of conceptual complexity, only either allowing arbitrary chaining or disallowing chaining entirely is justifiable, as opposed to specifying and implementing rules to permit it but only in certain specific cases, especially considering the marginal benefit. So we settled on agreeing with Larry’s original design decision to disallow them.

[P5P posting of this summary]

(English below)

Hallo zusammen,

wir laden Euch herzlich ein
zum Deutschen Perl/Raku Workshop 2026.

Der Workshop findet nächstes Jahr vom Montag 16. März bis
Mittwoch 18. März in der Heilandskirche in Berlin. statt.

Die Webseite und der Call for Papers sind bereits online. Wir freuen uns auf viele interessante
Vorträge!

Über Unterstützung durch Sponsoren freuen wir uns immer. Wenn Ihr bzw. Eure
Firma den Workshop unterstützen möchtet, wendet Euch gerne an uns. Wir finden gemeinsam sicher eine Möglichkeit!

Wenn Ihr Fragen an die Organisatoren habt, erreicht Ihr uns am besten
direkt unter orga2026@german-perl-workshop.de .

Wir freuen uns auf Eure Teilnahme,
Max Maischein für die Organisatoren und Frankfurt.pm

Wir arbeiten noch an
Hotelempfehlungen und veröffentlichen diese auf der Webseite.

---

Hello everybody,

we cordially invite you
to the German Perl/Raku Workshop 2026.

The workshop will take place next year from Monday 16th May to
Wednesday 18th March in the Heilandskirche in Berlin..

The website and the call for papers are already online.
We are looking forward to many interesting
presentations!

I thought it might be fun to write a "polymorphic virus", but that would involve learning executable file formats and machine code, which sounds like a lot of effort. So instead I went for the next best thing: Perl instead of machine code, and self-replicating code in the form of a quine rather than "infecting" other executables.

When you run this code, it will output a new version of itself, which you can run again to get another version, etc. Unlike a regular quine, which will produce an exact copy of its source code, this program is polymorphic: Its output is functionally identical to the original, but the code might look completely different. This is just a proof-of-concept, but it does try to introduce variations in all parts that a simple static scanner might use for detection (such as signatures in an antivirus). There are still fixed parts, but they're small and generic (such as ; or =) and can be found in most any perl script.

(my $Edw70Kp = "|ygn`hjs\nmo\\yjc]eyuy}YUl[h^y:YWyw\nmo\\ym`gnyu\nyyyygsy\"}mnl#y7y:Y5\nyyyyl_nolhymjlchn`\"{p~p^{&y}mnl#\nyyyyyyyyc`yl[h^\"#y6y*(,5\nyyyy}mnly7xymu\"UXy'xW#v\"U{V}V:VVW#wu\nyyyyyyyy^_`ch_^y},y9y{VV},{y4\nyyyyyyyy}+y_ky{Vh{y9y{VVh{y4\nyyyyyyyymjlchn`\"{VVr~*,r{&yil^y}+#\nyyyyw_a5\nyyyy!{!y(y}mnly(y!{!\nw\n\ngsy}p[ly7y!}!y(ydichy!!&yjc]e\"![!y((y!t!&y!;!y((y!T!&y!Y!#&yg[jyjc]e\"![!y((y!t!&y!;!y((y!T!&y!Y!&y!*!y((y!3!#&y'-y((yl[h^y++5\ngsy\"}ip[l#y7y}?^q1*Ejy7xy)7yV}\"Vq%#y7)5\n}?^q1*Ejy7xym)V}}ip[lV\\)}p[l)a5\n\ngsy}h_rny7yjc]e\"!!&y!gsy!&y!ioly!#y(y}p[ly(y!y!y(yjc]e\"!7!&y!(7!&y!vv7!#y(y!y!5\n\nc`y\"l[h^\"#y6y*(/#yu\nyyyygsy}ey7ydichy!!&yg[jyuy]blyl[h^y,/0ywy+y((yf_hanb\"}?^q1*Ej#5\nyyyy}h_rny(7ym`gn\"}e#y(y!yXy!y(ym`gn\"}eyXy}?^q1*Ej#5\nwy_fm_yu\nyyyygsy}lmy7yil^y{y{5\nyyyygsy}l_y7yil^y{x{5\nyyyygsy}lqy7y}l_y'y}lm5\nyyyygsy}^y7y+y%ychnyl[h^\"}lq#5\nyyyy\"gsy}^j_`y7y}?^q1*Ej#y7xym)\"Uy'xW#)]bl\"\"il^\"}+#y'y}lmy%y}lqy%y+y'y}^#y~y\"}lqy%y+#y%y}lm#)_a5\nyyyy}h_rny(7ym`gn\"}^j_`#5\nyyyygsy}hy7y]bl\"}lmy%y}^#5\nyyyy\"gsy}gy7y}h#y7xynl)z'xy)y'x)5\nyyyym)\"UV)V'VVW#)VV}+)ay`ily}g&y}h5\nyyyy}h_rny7y{\"}h_rn#y7xy{y(yjc]e\"!nl!&y!s!#y(y{)y'x)}h'xy'}g){5\nw\n}h_rny(7y!5y!5\n\n}h_rny(7yjc]e\"{_p[fy}p[l{&y{m)X)}p[l)__{#y(y{Vh{5\n\njlchny}h_rn5\n") =~ tr/ -~/&-~ -%/; eval $Edw70Kp

Back to my favourite topic AWS, today I am exploring AWS S3 Bucket Events.
Please check out the link for more information:
https://theweeklychallenge.org/blog/aws-s3-bucket-events

On my last post I asked Gemini to create a product requirement document to outline a plan to improve the overall state of the ev-calc-pricing application. In this blog entry I will discuss my interaction with Gemini and how it increased code coverage of the ev-calc-pricing application. Below is an example of the prompts:

----
> review PRD.md for @ev-calc-pricing

╭────────────────────────────────────────────────────────────────────────────────────────────────────────────────────╮
│ ✓ ReadFile PRD.md │
╰────────────────────────────────────────────────────────────────────────────────────────────────────────────────────╯
✦ The PRD.md outlines a plan to refactor the ev-calc-pricing application to improve maintainability, data accuracy, and
robustness.

Key issues identified:
* Manual, hardcoded electricity rate data in StateRates.pm.
* Minimal test coverage.
* Unused scripts and lack of input validation.

The plan focuses on four epics:
1. Automated Data Pipeline: To fetch, process, and load electricity rate data automatically.
2. Comprehensive Test Suite: To ensure accuracy and stability of calculations and data loading.
3. Code Refactoring and Cleanup: To remove hardcoded data, unused scripts, and consolidate data files.
4. Enhanced User Experience: To add input validation and better user feedback.

The code is in this gist

insert_multi_p will let you insert multiple rows in Postgres with a single query, like this:

Get at the usual place...
Elsewhere, I've moved house, into a retirement village.
Yes, folks. I'm 75, much to my horror and astonishment.
It was an exhausting process, but I'll settled in now. And still programming!
And not just the wikis. I have various other projects I can get back to now I've moved.
Why move?
Because I downsized. The price difference gives me a little bit of money in the bank.

One more contribution, OpenAPI::Linter to validate and lint OpenAPI Specification. For more information, please follow the link:
https://theweeklychallenge.org/blog/openapi-linter

In my previous blogpost I briefly discussed the use of Gemini Cli on a Perl dancer application to analyze its codebase. The next step is to generate a product requirement document. Why is this important ? well I had a bad experience with Gemini on another application where I allowed it to roam free "YOLO" mode and it basically started fixing all the problem areas one after another for about an hour or so until my free trial of Google Gemini expired for the day. This resulted into a completely rewritten application that was not able to run due to so many different errors. The cool thing is that I had version control so a good old "git reset --hard Head" cleared up my project and I could start over again.

Only Paul and Aristotle this time.

We had a small amount of helpful feedback on the named signature parameters PR. Paul wants to merge by the end of the week for the purposes of inviting more feedback, assuming no issues are raised in the meantime.

[P5P posting of this summary]

Every year we “welcome” a new bunch of trainees into our department. Young, intelligent and enthusiastic, their psyche and physique have yet to be shaped to accommodate cynical scepticism, efficient laziness, and an integument thickened by years of abuse into something that offers natural protection from radiation emanating from the monitors they will stare at all day playing Solitaire.

One such fellow, let’s call him Nik the Greek, came up to me with that sickening joie de vivre characteristic of youth, and proceeded to reveal how eager he was to demonstrate his enormous intellectual assets. I would have raised an eyebrow, had I the energy to do so. But been there, done that. I was once his age I suspect, though either I can’t remember or have developed a block to my memories as an act of self-preservation.

Dancer2 2.0.1 has been released. It's a small maintenance release that fixes a few broken documentation links.

Enjoy, and keep Dancing!

Jason / CromeDome

In the last few months I have been learning Flutter and Dart and recently I saw a youtube video from our very own Perl Wizard Randal Schwartz ( Vibe-coding with Gemini CLI ) where he is exploring the use of Google Gemini to vibe code Flutter applications. Gemini Cli is a command line tool that gives you the power of Gemini AI right in your command line prompt. In the beginning of Randal's adventure with Gemini he wrote this AI prompt "review the app @youtube_watcher. Tell me the Good, the Bad and the Ugly." and AI delivered a very detailed response on what is and isn't working within the application.

After seeing this very detailed report I decided to do the same on ev-calc-pricing a perl dancer project I worked on and I was amazed to see Gemini work on a perl dancer project. At this point I realize that Gemini is capable of assisting coders in any language/ framework and it can provide insight on software engineering best practices for you application.

Introducing YaraFFI, minimal Perl FFI bindings for the YARA malware scanning engine.
For more information, please follow the post below:
https://theweeklychallenge.org/blog/yara-malware-scanner

https://binary.golf/6:

Binary Golf Grand Prix is an annual small file format competition, currently in it's sixth year. The goal is to make the smallest possible file that fits the criteria of the challenge.

This year's BGGP challenge was to output or display 6. I always wanted to work with actual machine code, so I decided to submit a DOS COM executable. Why? Because the COM format has no headers or other metadata; you can just put some x86 instructions in a file and run it directly.

Having no experience with DOS, I started by looking up a "hello world" example and found https://github.com/susam/hello:

MOV AH, 9
MOV DX, 108
INT 21
RET
DB 'hello, world', D, A, '$'

All three of us attended.

• We touched on the recent discussion about the classification of modules included with the perl distribution. We agreed that the PSC and p5p need to do a better job of tracking which modules have active maintainers and who they are. Something like a dashboard would be useful for this, and we identified as a starting point that it would be good to have an up-to-date overview of dists, their maintainers, and whether they are active. Maintainers.pl probably already covers the list of dists but it would be useful to split the data out into a separate file so it could be used in other scripts, which could also populate records with additional data, outside of what Maintainers.pl needs, for their own purposes. For example a tool for querying PAUSE for the maintainers of dual-life dists and flagging deviations could check a custom field where known deviations (along with a comment) would be recorded, so as to not flag them.
• We had a somewhat surface-level discussion about the future of stdio in Perl. Leon has been thinking about this and intends to write a separate mail to p5p about it.

[P5P posting of this summary]

Available from the Wiki Haven.
I have still not had time to update CPAN::MetaCustodian, so it does not yet work correctly with the latest version of Perl.Wiki.html.

Class::Mite is getting better relatively as numbers shown in the post below: https://theweeklychallenge.org/blog/bless-vs-class-mite