unkaktus

Enabling UART on Alpine Linux on Raspberry Pi Zero 2W

Sat, 25 Apr 2026 00:00:00 +0000

By default, Alpine Linux will spawn a tty on the built-in serial. That’s not what you want when you want to talk to another device over UART.

Here’s how to prevent that.

In /boot/usercfg.txt, add:

enable_uart=1

In /boot/cmdline.txt, add:

console=null

In /etc/inittab, comment out:

# enable login on alternative console
ttyS0::respawn:/sbin/getty -L 0 ttyS0 vt100

Unite, Divide, and Dress It Up! -- _ASCII art v. LLM_

Sun, 19 Apr 2026 00:00:00 +0000

Let’s be frank: the internet was taken over by LLMs and AI slop. As time goes on, it is increasingly hard for humans to distill truthful information from the oceans of LLM-generated garbage. Unfortunately, these texts often look legitimate due to elaborate grammar and a convincing way of prose, while they often contain idiotic mistakes and produce nonsense information (for juicy details, check out a great write-up by Kyle Kingsbury titled The Future of Everything is Lies, I Guess: Information Ecology, especially the Information Ecology section).

Yet, due to the way LLMs work, some simple tasks, such as reading analog clocks or solving simple riddles in one word, are out of their reach. Once, I was curious whether LLMs can decode a weird kind of text–the one encoded with ASCII-art fonts. Trying this, I got truly amused by the results, and a little bit surprised. After all, the way it handles ASCII art is very revealing about the LLM’s inner workings.

Maybe read a byte - how Go crypto library prevents you from getting overdependent on it

Mon, 23 Mar 2020 00:00:00 +0000

While implementing an ECDSA request signature algorithm I was writing unit tests for it. The tests should work in a reproducible way: we generate the same private key each time, sign constant data with the same random (which is needed for ECDSA) - we get the same signature. It seems quite straightforward.

Using reproducible random stream

Looking at the documentation, we see that we should pass elliptic curve parameters and the random stream we want to use.

About

Mon, 01 Jan 0001 00:00:00 +0000

Hey there!

I am Ivan Markin.

I work on compact binary mergers in the framework of numerical relativity, mainly on black hole-neutron star mergers. I contribute to the LIGO Collaboration by producing physically-accurate visualizations of the exceptional events, finding ways to reduce carbon footprint as part of the Climate and Sustainability Committee, and providing the NR waveforms for more accurate waveform models.

Contact

Email
Signal

Interesting reads

Mon, 01 Jan 0001 00:00:00 +0000

LLMs and their proliferation

AI Assistance Reduces Persistence and Hurts Independent Performance (2026)

12 Graphs That Explain the State of AI in 2026 (2026)

AI Models Fail Miserably at This One Easy Task: Telling Time (2025)

A Case of Bromism Influenced by Use of Artificial Intelligence (2025)

A weird phrase is plaguing scientific papers – and we traced it back to a glitch in AI training data (2025)

Hiding in Plain Sight: Weaponizing Invisible Unicode to Attack LLMs (2025)

Publications

Mon, 01 Jan 0001 00:00:00 +0000

Numerical simulations of black hole-neutron star mergers with equal and near-equal mass ratios

Ivan Markin, Mattia Bulla, Tim Dietrich

e-Print: 2601.19405 [astro-ph.HE]

General-relativistic radiation magnetohydrodynamics simulations of binary neutron star mergers: The influence of spin on the multimessenger picture

Anna Neuweiler (Potsdam U.), Henrique Gieg (Potsdam U.), Henrik Rose (Potsdam U.), Hauke Koehn (Potsdam U.), Ivan Markin (Potsdam U.) et al.

e-Print: 2510.14850 [astro-ph.HE]

DOI: 10.1103/mxlf-8sbm (publication)

Published in: Phys.Rev.D 113 (2026) 4, 043038

Challenging a binary neutron star merger interpretation of GW230529

Solaris

Mon, 01 Jan 0001 00:00:00 +0000

Solaris cluster

Solaris is a carbon-free not-so-high performace computing (NSHPC) cluster located in Berlin.

Access call

Solaris is open to applications for carbon-free, open-access scientific computations. The preference is given to early-career and generally underrepresented researchers.

To apply, write to solaris-apply@unkaktus.art

`solaris-c01`

Component	Info
Rack	PowerEdge R620
CPU	2x Intel(R) Xeon(R) CPU E5-2665 0 @ 2.40GHz
RAM	4x DDR3 4GiB
10Gbit Network	2x Ethernet Controller 10-Gigabit X540-AT2
1Gbit Network	2x I350 Gigabit Network Connection
Hard drive	HITACHI 500GB HDD
PCIe Slots	Free
Operating System	Alpine Linux 3.24.0

unkaktus

Enabling UART on Alpine Linux on Raspberry Pi Zero 2W

Unite, Divide, and Dress It Up! -- _ASCII art v. LLM_

Maybe read a byte - how Go crypto library prevents you from getting overdependent on it

Using reproducible random stream

About

Hey there!

Links

Contact

Interesting reads

LLMs and their proliferation

Publications

Solaris

Solaris cluster

Access call

solaris-c01

`solaris-c01`