HNHacker News
TopNewBestAskShowJobs

jcubic

604 karma · joined April 11, 2011

Jakub T. Jankiewicz twiter: @jcubic www: http://jcubic.pl/me

I'm mostly Front-End Developer, I do Open Source and I'm also Wikipedia Editor and Blog author.

[ my public key: https://keybase.io/jcubic; my proof: https://keybase.io/jcubic/sigs/SNxeHIzd0GmaQTchY2dLDsnmgTTPHj2rDgnKTMIvRfw ]

submissionscomments
jcubic··on Ask HN: What's your current AI agentic setup?
I use Claude Code with Opus 5.5 via ACP inside the GNU Emacs Agent-Shell.

I used Open Code, but they stopped supporting Claude, so I was searching for something different (I had a free 20x Max plan as an open source maintainer). First used Claude Code and then found out about Agent-Shell. Now I'm using the Claude Pro plan.

jcubic··on Ask HN: Design My YouTube Feed
But you know that you don't need main algo feed right?

You can open:

https://www.youtube.com/feed/subscriptions

And only see videos from channels you're subscribed to.

jcubic··on Ask HN: What are you reading?
Finally started reading "A Philosophy of Software Design". It was on my shelf for ages. I have the 1st edition; luckily, you can grab new chapters from the 2nd edition from the author's website.
jcubic··on Ask HN: What are you working on? (September 2026)
Working on a Unix simulator in the browser.

https://hacking.cafe

https://github.com/jcubic/hacking.cafe

jcubic··on Ask HN: What are you working on? (August 2026)
Resumed my work on continuations and tail call optimization in my Scheme interpreter called LIPS. Just released a new beta version: https://lips.js.org/
jcubic··on Ask HN: How do you keep up with HN these days?
I've created a tool called Mutimon:

https://github.com/jcubic/mutimon

I got an email about the latest news in my inbox.

I've set a threshold of > 250 points + extra for Ask HN

jcubic··on Writing by hand is good for your brain
When you are writing notes during lectures, you should not write word for word. If you do, you will never catch up with what is said. People often speak faster than they write.

If you want to take notes during lectures, you need to learn how to summarize in your own words. You need to write the stuff down so you can remember what was in the lecture. Something you can summarize the whole sentence with one word. Notes are for you, not for other people to read.

jcubic··on Ask HN: What Are You Working On? (July 2026)
Just finished working on a new version of customizable Clarity Linux (GTK+) icons.

Created a new website and new icon manager: https://clarity.pl.eu.org

Complite - Elventy template/starter

https://complite.jcubic.pl

And a Polish WikiZEIT project:

https://wikizeit.edu.pl

And ALT - LanguageTool for Emacs

https://github.com/jcubic/alt

jcubic··on Ask HN: Is anyone experimenting with different ways of using LLMs for coding?
I'm using agent in GNU Emacs to debug the same instance of Emacs/agent. I also extend the agent by the same agent while Emacs is running.
jcubic··on I Stored a Website in a Favicon
Does't work for me. It rendered some garbage:

:f3=Ygbukte!in"c"Hbviann:1h3> =n= " Exgtyvhkle znt%pfsdafipg thfivlmu "vas dcdpeed hrondbvjbno"rixfls, ;.q>

I use Helium on Linux with Polish locale.

jcubic··on Ask HN: What tools are you using for AI-assisted code review?
No I did nothing. I use it as a first check before I review the code myself on my Open Source projects.
jcubic··on Ask HN: What tools are you using for AI-assisted code review?
I mostly use CodeRabbit via GitHub PR

https://www.coderabbit.ai/

jcubic··on Ask HN: What Are You Working On?
I'm working on my new project WikiZEIT (where I write about Wikipedia and SEO/GEO). https://wikizeit.edu.pl

The website is in Polish, but there is a translate button at the top nav.

I'm also working on improving the appearance of my own name (Jakub T. Jankiewicz) in Google.

jcubic··on Ask HN: What are tools you have made for yourself since the advent of AI?
Created a few Open Source tools:

Open Camera Control https://github.com/jcubic/open-camera-control - that allows me to control the settings of my DSLR while I'm recording myself.

Horavox - https://github.com/jcubic/horavox - A speaking clock

Mutimon - https://github.com/jcubic/mutimon - a config driven web scraper (found this post from the email sent by this tool).

ASCII-Globe - https://github.com/jcubic/ascii-globe - JavaScript library that renders a rotating earth or any map. Can be used to add animation to your website.

jcubic··on Ask HN: What are you working on? (May 2026)
I'm working on a few projects:

* ASCII-Globe => https://github.com/jcubic/ascii-globe

* Horavox (a speaking clock) => https://github.com/jcubic/horavox

* Mutimon (generic config driven web scraper and notification system) => https://github.com/jcubic/mutimon

jcubic··on Ask HN: What Are You Working On? (April 2026)
I'm working on my Open Source speaking clock (mostly for myself):

https://github.com/jcubic/speaking-clock

It uses local AI models for the voice.

jcubic··on Chicago artist creates tourism posters for city's neighborhoods
Link not available in Europe :(
jcubic··on Regex Golf Game
This is old, found it via Facebook memory (when I posted everything from Twitter), I played this game 11 years ago.

I'm glad that the game still exist.

Now you can cheat a bit by using AI, but it's still fun.

jcubic··on LIPS: Scheme based Lisp interpreter in JavaScript
- in Gambit History works on lines not S-Expressions like in LIPS

- With LIPS you don't need any new syntax to integrate with JavaScript you just use JavaScript directly (let ((msg "hello") (console.log msg)) SIX syntax doesn't look like Scheme.

- Help popup documentation, with LIPS you have documentation directly in the REPL (when you hover over the symbol) and you can access docstring as strings and assign them to values.

- You can create new syntax similar to scheme vectors and make representation the same as code

- You can manipulate almost everything in the language like environments that you can modify

- LIPS show stack trace not one line which gives an error that makes it easier to find where the error happens.

- The Bookmarks allow to run the REPL on every page even PDF files with R7RS spec.

- You can actually run the code that uses quotes (’ The apostrophe symbol) from the spec if you use syntax extension to add new syntax.

jcubic··on LIPS: Scheme based Lisp interpreter in JavaScript
Author here. That's why it's not listed on the official scheme.org website as one of the implementations. I was told that to me called Scheme, you need TCO and continutations.

I made one attempt to implement them some time ago but failed. The code was not working. I based my implementation on someone else code. And later turned out that the call/cc that I based my code pm was not even full continuations and failed my test case.

Most Toy Scheme implementations don't have TCO and call/cc so I can't use them as a reference. But I have an implementation that is really promising that implemented them, the code is very minimal and I can base my code on that.

jcubic··on LIPS: Scheme based Lisp interpreter in JavaScript
Unfortunately, I don't have access to a Mac. I can only run Safari at BrowserStack. So I can't test it and fix it.

But this is Open Source and anyone who has a Mac can test it and fix this issue. I can't.

jcubic··on LIPS: Scheme based Lisp interpreter in JavaScript
LIPS has documentation builtin into every function. You can see the docstring when you hover over the name of the symbol in the REPL. It also has auto-indent. Also if you press enter you can get back and modify previous lines of code. History doesn't repeat lines only full S-Expressions so it's easy to rerun a big chunk of code.

Even though Try Gambit is a REPL it's not very user-friendly.

jcubic··on Ask HN: Tell us about your project that's not done yet but you want feedback on
I just loaded a page from Europe, it took few seconds to load the images. I thought the page was broken, there were no loader of any kind.
jcubic··on Ask HN: Why isn't JSON-RPC more widely adopted?
I was told by the author of tRPC, that they use JSON-RPC behind the scene.
jcubic··on Ask HN: What's your proudest hack?
This reminds me my old Laptop with Linux installed that had Optical drive broken and no USB boot option, there was also no option to buy new Optical Drive. I was moving directories around to make some space on root directory. I've moved /var/ to /home directory and create symlink and it worked. But then later I wanted to do the same with /usr directory that had all shared libraries in /usr/lib/. In the process of moving files got some error I was not able to use any binary file like cd, ls or ln. Only applications that was running was working.

I was certain that the laptop was dead and I will not able to use it anymore since I will not be able to install new system. So the task was to copy somehow all my important data. Luckily I was using Firefox and I've had FireFTP installed, so I've borrow my mother Windows laptop and installed FTP server and was able to copy my data over WiFi. Later it turns out that you could buy used DVD burner for that laptop, so it was resurrected and after installing Windows XP I've given that laptop to my mother.

jcubic··on Ask HN: What's your proudest hack?
I was reading Twitter and someone posted a tweet with a photo and that it was created in CSS. It turns out the post was a hoax, but I figured that you can actually create photos in CSS, using box-shadow hack (you create 1x1px div and each pixel is single box-shadow). I was using it few years ago to create pixel graphic editor demo. So I've created something quickly on CodePen that get all pixels and create one big box-shadow. When I opened Google Chrome Dev Tools to copy the code it frozen because it was few MB of box shadow data. I was able to copy the text eventually and create HTML file. Later I've added a way to download a HTML file with your image on CodePen.

Here is the demo: https://jcu.bi/css-image

jcubic··on Ask HN: Does anyone use Bayesian stats to filter interesting stories on the Net?
I read HN mostly via email newsletter and I'm interested in like 5% of the content, if I read one or two articles from newsletter it's good. The same as with other newsletters I'm subscribe for. Each social network has different content post by different people. If you merge all those places into one thing you can't keep up with the flood of post.

I've once was subscribed to a few subreddits via RSS and I was not able to read even headlines and they were accumulation over time.

I was also trying HN100 RSS (post that reach 100 points on HN), and most of the stuff was not interesting to me. So even reading headlines was a waste of time. Not to mention that I was not able to keep on reading the headlines to have 0 RSS inbox.

What I would like to see only post that I would really like, and I believe that you can train SMAP filter to do that.

And about SMAP filtering I don't want to filter SPAM as in an email SPAM only stuff I'm not interested in and I see a lot of post on first page on HN that I'm not interested in.

I would like stories recommendation based on my interested not common interest on every HN reader. Most HN readers are not average HN reader.

jcubic··on Ask HN: What book have you re-read 3x or more?
The Witcher Saga by Andrzej Sapkowski. I'm Polish so I've read the original. This was the best fiction book I've ever read. Also Neil Gaiman's American Gods and Neverwhere.
jcubic··on $9.99/month
I don't know about other countries but in Poland we have subscription based phones for ages from mobile operators. You get the phone for 1PLN but you pay for it with the bill for 1-2 years, when you get another phone with new agreement. I don't know about you but I call that subscription for device.
jcubic··on Ask HN: Can I see your cheatsheet?
I completely forget that I have this function in my dot files:

doc () { curl "https://cheat.sh/$1" | less }

Page 1 of 3Next →