MQTT Cheat Sheet

The MQTT (Message Queue Telemetry Transport) messaging protocol is a lightweight protocol well suited for the Internet of Things. It is a simple protocol and an ISO standard. It comes with an extensible reference documentation.

To help me learn about it and simplify my work flow, I created this cheat sheet (warning: PDF) which highlights the most relevant details about the protocol. You can also see it online here.


Linux fanzines

Although man pages are essential for anyone doing serious work on Linux and other Unix-like operating systems, it’s hard to advocate for them as being user friendly and easy to read. Therefore, evangelists invent all sorts of things to spread knowledge about their favorite tools and technologies: tutorials, e-books, videos, etc. There’s even a coloring book that teaches how SELinux works. Now we have one more addition to the mix: fanzines. If you like them, this website has some very interesting and funny zines about programming, debugging and Linux in general.


VIL: Very Important Links (updated)

Just some important links that might be useful for others.

Ptrace is a linux syscall that allows you to manipulate process. It’s commonly used to implement debuggers, although you can do quite a lot of other interesting stuff with it:

This link shows how to prevent having to enter a password everytime your are managing your Linux VMs. This is pretty handy if you are using vagrant and/or creating/destroying a lot of them:


Fedora Linux 22 on Macbook Pro Retina

I have Late 2013 MacBook Pro Retina (MacBookPro11,1 (13″) (A1502)) and I wanted to run Fedora 22 on it. These are just some tips to solve some common problems about running Linux on it:

1. Configure wireless:

First install kernel-devel:

The follow the steps here (basically: install rpmfusion, then broadcom-wl, then run sudo akmods).

2. How do I switch the Command key and Control key on a MacBook Pro? Check here.

3. Adjust HiDPI settings. If you are running Cinnamon, you can just adjust it in the fonts settings panel. If you are not, you may need to export GDK_SCALE for some applications. You can find additional details in this link.

4. Touch pad: enable the right click on the right bottom area of the touch pad.


You can learn more about tweaking the Macbook touchpad here and here.

5. Bluetooth: does not seem to work yet, sorry.

Recommended reading

Quick post to share some interesting material I came across the Web:






JSON manipulation: reference material

While working on ways to export my backlog in Trello, which I wrote about in this post, I came across the following articles that I think might be useful for those manipulating JSON data:

The titles are speak for themselves. Have fun.

Development Goodies

These are just some development-related links and articles I have read in the last weeks which I think are worth mentioning: