Recommended keyboard settings for Productivity and Usability, for European Programmers

TLDR: setxkbmap -layout us -variant altgr-intl and become a happier programmer.

The case for QWERTY for European Programmers

If you’re working on Unix / Linux, or C based programming languages, it can make sense to switch to the qwerty(us) keyboard layout. Why ?
Unix, C, Perl, Java, and most of programming languages have been conceived on QWERTY keyboards.
So when the designers choose  special characters to use for the language synthax, they simply choose what was easy to access on their own keyboard. This has been historically documented for the vi editor.

To give an example, using an Unix shell you have to type the dot . and slash / symbols quite often to navigate the filesystem. The two keys producing these symbols, are nicely aligned on a QWERTY layout and do not require a key combination to be entered. So you can quickly enter something like ‘../..’ using a single hand.
Now using a QWERTZ layout, like in Germany / Austria, you have the ‘.’ symbol easily accessible, but you need to combine two keys ( Shift + 7 ) to get a ‘/’.
And if you are a poor soul using an AZERTY layout, to get the ‘.’ and ‘/’ symbol you need each time a key combo.
The need of key combos is bad not only for speed (multiple keys to lookup) but also for usability,  as you have to stretch your fingers to reach the key if using a single hand, provoking repetitive strain injury. You might be smiling but this is commonly known amongst Emacs Users, due to the prominent use of commands using Ctrl and Alt combos, and led to the creation of an Emacs Ergonomic wiki.

This goes as well for many symbol commonly used in programming languages, think for instance about the  semicolon ‘;’ for terminating a statement, the ‘[’, and ‘]’ symbols for defining an array, and the backslash ‘\’ for escaping.
All these keys are accessible via a single keypress on qwerty and require key combos on qwertz and azerty. No wonder Linux, Minix and BSD were invented on non-azerty layouts: in France we were still busy typing the path to the source code, when in other parts of the world people already had the file open in their editor.
You don’t need to throw away your existing keyboards when learning the qwerty (us) layout: for a couple of euros, you can find on ebay alternate keys stickers to put on your laptop.

Accessing keys with diacritics with the AltGr International variant

Now if you want to switch to a qwerty keyboard layout, and you’re French or German, you might wonder how to access the characters with diacritics, the é and è of French and ü and ö of German.
Fortunately there is a very clever keyboard variant for the us layout who uses the AltGr key, to make all these keys accessible, just hiding them behind the AltGr key.
Need é ? that’s just AltGr + e away. Needs ç ? That’s just AltGr + , Needs ö ? AltGr +p
See the coolness of that ? You can type all international diacritics in an easy way, and there are even keyboard stickers for that too.

Now how to access to this layout of wonder ?
You can configure the layout and variant in Xorg, in debian/ubuntu that would be entering in /etc/default/keyboard

XKBLAYOUT="us"
XKBVARIANT="altgr-intl"

After restarting the X server, you can check that the settings have been applied with

setxkbmap -print -verbose 10

If using Gnome, you can also set the keyboard layout and variant by changing the schema org.gnome.desktop-inputsources, which will override the desktop-agnostic settings of /etc/default/keyboard.
For this you can either call

dconf write /org/gnome/desktop/input-sources/sources "[('xkb', 'us+altgr-intl')]"

or navigate with the gui tool dconf-settings to org.gnome.desktop-inputsources and set the value there.

If you want to further improve your keyboard layout, you can also have a look at swapping Ctrl and Alt, as described here (French language article) Happy hacking !