Declaration of VAR

and some other stuff

On 19.05.2021 the website was moved to https://decovar.dev/. This is just a mirror now.
  • Home Assistant on Vero V with Docker

    2024-08-16 | 55 min read

    Eventually I got tired of constantly re-signing and re-uploading Kodi to my Apple TV (and being stuck with an old version). So I got a Vero V instead, and immediately it became clear that I should have done so from the beginning. Buying Apple TV was a mistake: like I said before, if not for running Kodi, Apple TV is a pretty useless device (especially now that I have a TV that supports AirPlay).

    Vero V with connected SONOFF Zigbee 3.0 USB Dongle Plus-E

    Around the same time I entered the domain of home automation. At first it was just Homely (a norwegian home security system), which comes with their own hub and a (not very large) set of supported devices/sensors. But soon enough I discovered that it’s all just a Zigbee network wrapped into a user-friendly package, so I could do more with my own hub and a much wider (and cheaper) collection of devices and sensors. Shortly after that realization I stumbled upon Home Assistant, as all roads lead to it, and, you guessed it right, I decided to host and run it on that same Vero V device.

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  • C++ library in an Android application

    2024-02-12 | 22 min read

    We have a C++ library, which our customers are using on a variety of platforms. Mainly in desktop applications on Windows, Mac OS and GNU/Linux, but there are also web-applications (for which we compile it into WebAssembly with Emscripten), and now we got a request to make it work in Android applications too (or rather to provide a binding/wrapper).

    Android Studio, loading C++ library

    This particular example will be about a Kotlin-based application. I don’t know what would be different in case of a Java-based application, but I suppose that principal things should be more or less the same in both.

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  • Oracle Cloud is a nasty piece of shit

    2023-12-03 | 13 min read

    I’ve been using Oracle Cloud Free Tier (“Always Free” resources) for 2.5 years (since I moved my website from GitHub pages). It was indeed absolutely free of charge, and it was really great while it lasted.

    Oracle Cloud, planned outage

    But two days ago my website suddenly went down along with the server and all the content on it. Without a notice/warning, with no explanation and without a way to restore the data (fortunately, I haven’t actually lost any).

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  • Compiling C++ into WebAssembly with pthreads

    2023-11-20 | 14 min read

    If a C++ program utilizes multithreading via pthreads, then compiling it with Emscripten into WebAssembly requires setting certain flags for both compiler and linker. In addition to that, web-server that will be hosting the resulting web-application also requires some configuration.

    Meepo clones dancing on top of the WebAssembly logo with pthreads

    A couple of years ago I compiled a Qt-based application into WebAssembly using Emscripten, and I did mention pthreads there too, but it was very briefly and without any details. And as it turned out, there are some interesting moments in there which are worth being documented.

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  • CMake target_link_libraries() scopes

    2023-07-22 | 27 min read

    The CMake’s target_link_libraries() function has different scopes (PRIVATE/INTERFACE/PUBLIC), and I never understood what exactly each one of them means and how do they actually affect the final result.

    CMake, linking 3rd-party dependency, your SDK and application

    As there is a limit for how long one can postpone one’s ignorance, it finally came a time for me to investigate the matter, which I did by (reading the documentation and) conducting a small experiment of my own.

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  • Building stuff from sources on Steam Deck

    2023-05-28 | 42 min read

    My previous article about Steam Deck has exploded in size, so I decided to move the part about installing packages and building stuff into a separate article.

    Steam Deck, Konsole in Desktop mode and docked with mouse and keyboard

    But it’s not just already published parts, there are some new things too: in particular, I’ve managed to build Qt (both shared and static configurations) and used it to build my own applications.

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  • Steam Deck

    2023-04-10 | 126 min read

    If you play games (actual games, not press-X-to-win blurry movies), then undoubtly you have heard about Steam Deck. If you haven’t, then you can probably just go watch some more of your favorite titles on PS/Xbox/Switch/whatsthename instead of reading this wall of text.

    Steam Deck, Космические рейнджеры

    Yes, I’ve got my very own Steam Deck too. And as many have already said, it does exceed all the expectations (and then some).

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  • Норвежское гражданство

    2023-01-15 | 42 min read

    Наконец-то получил гражданство Норвегии (Королевства Норвегия!).

    Норвежский и русский паспорта

    Шёл я к этому достаточно долго, и было это не очень просто. Но самой сложной частью было найти работу в Норвегии, чтобы выехать из России; а после переезда в Норвегию процесс становления гражданином протекал, можно сказать, в автоматическом режиме, потому что от меня самого требовалось довольно немного, и мало что (если вообще хоть что-то) могло пойти не так.

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  • Qt на микроконтроллерах

    2022-12-24 | 7 min read

    Эта статья создавалась как перевод поста (который почему-то больше не доступен) из блога The Qt Company для публикации на Хабре. Но НЛО сказало, что статья рекламная, и опубликовать не дало.

    Qt on MCU

    Я бы не сказал, что это рекламная статья, хотя в ней действительно есть ссылки вида “свяжитесь с нашими консультантами” и там и сям упоминается коммерческая лицензия. Как бы то ни было, на Хабре статья так и не вышла, но вот теперь спустя четыре года (лучше поздно, чем никогда) выходит здесь.

    This article in english 🇺🇸.

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  • Qt on MCU

    2022-12-24 | 8 min read

    On the 2018-05-03 there was a post published in The Qt Company blog: “Qt on Microcontrollers”. It was about the first PoC of Qt running on several selected MCUs. I say “was”, because for unknown reasons that post is no longer available in the Qt blog.

    Qt on MCU

    All the work on that PoC was single-handedly done by Mikhail Svetkin, who was an embedded software developer in The Qt Company back at the time, and looks like the post was taken down at some point after he left the company (Internet Archive has the last snapshot on 2019-05-02). Perhaps the new project owner didn’t like something about that article?

    Anyway, I thought I’ll resurrect the post and publish it here for the history. Everything below is published almost as it was in the original post in the Qt blog.

    Эта статья на русском 🇷🇺.

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