This page contains a few notes taken while building Deep Pi Car.

Goal

Building a tiny self driving car.

End Result

Resources

This sample project.

This medium blog.

Equipment …

I’ve been reading a lot about Graal recently, and with a bunch of related projets, I needed to remind myself what are the differences and uses for each. Here’s a brief recap and intro to those projects. Most of the research and work is …

Couple months ago, I read this article about hacking the Xiaomi Dafang camera to expand its capabilities. It’s a cheap $30 camera with neat features, such as MicroSD support, a …

Fantastic resource for anyone who knows Javascript, and wants to learn how React works in simple ways. Much different from the standard tutorials which try to get up and ready in a short time with tons of dependencies and little understanding of how it works.

https://github.com/kay-is/react-from-zero

Had an issue with gems not being downloaded from JFrog’s Artifactory. Basically it looked as if gem install could not be found on the Artifactory repo, yet manually browsing the repo, the gem was properly uploaded.

Reading the specs file that …

Stumbled upon a very nice explanation of the JVM memory, including garbage collector, tuning and related errors (watch here, in french). Here are some notes.

Garbage Collector

The classic garbage collector (included into the standard HotSpot JVM) …

There’s a Capture The Flag security challenge going on, organized by Stripe, the payment company. Capture The Flag security challenge are a series of technical weaknesses that participants need to find in order to find flags and capture them for …

In the PHP curl_multi_exec manual, a strange 3 loops are given as an example:

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<?php
do {
    $mrc = curl_multi_exec($mh, $active);
} while ($mrc == CURLM_CALL_MULTI_PERFORM);

while ($active && $mrc …

You have your code under SVN, and trying to deploy via Capistrano. You capify your root folder, you cap deploy:setup, everything works. How do you deploy a specific tag?

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If anything else doesn’t work, try this sample code:

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<?php
@apache_setenv('no-gzip', 1);
@ini_set('zlib.output_compression', 0);
@ini_set('implicit_flush', 1);
for ($i = 0; $i &lt; ob_get_level(); $i++) { ob_end_flush(); }
ob_implicit_flush(1);

// All you need is 256 spaces first
echo str_repeat(" ", 256); ob_flush();
for($i=0;$i&lt;10;$i++)
{
   echo $i,' ';
   ob_flush();
   sleep(1);
}