What would a keyboard optimized for Luxembourgish look like? Now with a real keyboard! | R bloggers

An optimized layout for a multilingual country

5 years ago I discussed what features a keyboard optimized for Luxembourg should have. I’m talking about Luxembourg, the country, and not Luxembourgish, the language, because in Luxembourg no one types only Luxembourgish. The most common language is probably French, with English coming in second. German comes in third, followed by Luxembourgish (some people might argue that German, in their own experience, is more broadly characterized than French, but I highly doubt this). Whatever the actual ranking, an optimized keyboard for Luxembourg should be one in which typing these 4 languages ​​is comfortable. That blog post from 5 years ago went into more detail about this (letter frequency and so on), but until today I left it on the back burner.

Now in LLMs it was trivial to keep working on this, implement an effort model and use an optimization algorithm to minimize the effort. Today I can present the layout I obtained:

(there is an error in the layout shown here, there are two “G”s; the one to the right of E should not be there, and should instead be a “,”. This is an error in the function that creates the heatmap, not in the layout itself.)

⚠️ This is a work in progress! The layout, the name, and even the methodology are all open to debate. I’m sharing this early because I’d like to hear from the community, especially those who type in multiple languages ​​every day. Your feedback will shape the final version.

Let me also clarify what my goal is with this: do I actually want to propose a layout that will be adopted nationally and become a standard? Well, maybe. But I’m certainly not going to do it alone. So if you’re interested, we can work together and write a layout that can actually be used by different operating systems and pitch it to decision makers.

France shows the way

In 2019, France officially adopted two new keyboard standards:

1. A revised AZERTY which solves many problems while maintaining familiarity
2. BEPO — a completely redesigned layout, optimized for French

I’ve been using BÉPO for years and I can honestly say it’s a game changer. Typing feels more natural, there are fewer finger movements and the learning curve, while steep at first, pays off considerably.

But the thing is: BÉPO was designed for French first and foremost. Luxembourg is unique because we need something that works for French And German And Luxembourgish And English.

The QWERTZ-LUX approach

So I started wondering: what would an optimized keyboard layout for Luxembourg look like? You can read about my findings herebut really, any optimized layout for any of these four languages ​​would actually work quite well; this is because 3 of these 4 languages ​​are Germanic languages, but also that the top 10 most used characters for these 4 languages ​​are essentially the same.

So I had three options:

1. Just suggest that we also adopt BÉPO
2. Create a fully optimized layout using these 4 languages ​​to set up the optimization problem
3. Keep QWERTZ as a basis for familiarity and move only a minimal number of characters to improve comfort.

I chose a middle path, inspired by that of Carpalx partial optimization philosophy. Martin Krzywinski has shown that you don’t need to remap the entire keyboard to reap the most benefits. Only 5 strategic key changes can be achieved 70% of the effort reduction of a fully optimized layout, while the learning curve remains manageable.

QWERTZ-LUX (final name pending) follows this principle. It is essentially a spin-off of BÉPO’s structure, but with changes that:

• Preserve familiar elements for QWERTZ users (Ctrl+Z, Ctrl+X, Ctrl+C, Ctrl+V keyboard shortcuts)
• Optimize the letter format for our multilingual corpus
• Provide direct access to accented characters (é, à, ü, ö, ç, ä) without dead keys

The home row had to change substantially, because the QWERTZ home row is simply too inefficient. But I tried to minimize disruption elsewhere, based on the partial optimization insight that the first few key changes matter most. Setting up the optimization problem with these constraints resulted in a keyboard layout that remains familiar, but at the same time is much more efficient.

The Corpus: what typifies Luxembourg?

To fairly assess keyboard layouts, we need text that represents what people actually type in Luxembourg. I created a balanced multilingual corpus with:

• 30% French — Administrative and business language
• 30% English — International communications
• 20% German — Media and education
• 20% Luxembourgish — Daily life and national identity

Again, your mileage may vary. When I first started working in Luxembourg, I only used English and French. Now I also use Luxembourgish more often, and I know people who only write French. Anyway, a national keyboard layout should be comfortable for all these languages.

What actually matters are the top letters in all languages E, N, S, T, R, I, Athe letters you want on your home row.

The effort model explained

Before we compare layouts, let’s first understand how we measure “typing effort.” I wrote an R package called lbkeyboard that implements a model inspired by Carpalxthe groundbreaking keyboard layout optimization tool created by Martin Krzywinski.

Total = Σ (base × frequency) + Σ (same_finger_penalty) + Σ (same_hand_penalty)
        + Σ (row_change_penalty) + Σ (layer_penalties)

# Load layouts
data("ch_qwertz")
data("afnor_bepo")
qwertz_lux <- create_qwertz_lux_keyboard()

# Effort weights (same as used throughout)
effort_weights <- list(
  base = 3.0,
  same_finger = 3.0,
  same_hand = 0.5,
  row_change = 0.5,
  trigram = 0.3
)

pangram <- "the quick brown fox jumps over the lazy dog"

# Calculate effort for each layout
pangram_qwertz <- calculate_layout_effort(ch_qwertz, pangram, 
                                          keys_to_evaluate = letters,
                                          effort_weights = effort_weights)
pangram_bepo <- calculate_layout_effort(afnor_bepo, pangram,
                                        keys_to_evaluate = letters,
                                        effort_weights = effort_weights)
pangram_lux <- calculate_layout_effort(qwertz_lux$base, pangram,
                                       keys_to_evaluate = letters,
                                       effort_weights = effort_weights)

data.frame(
  Layout = c("QWERTZ", "BÉPO", "QWERTZ-LUX"),
  Effort = round(c(pangram_qwertz, pangram_bepo, pangram_lux), 2),
  `vs QWERTZ` = paste0(round((1 - c(pangram_qwertz, pangram_bepo, pangram_lux) / 
                               pangram_qwertz) * 100, 1), "%"),
  check.names = FALSE
)
#>       Layout Effort vs QWERTZ
#> 1     QWERTZ 338.69        0%
#> 2       BÉPO 268.79     20.6%
#> 3 QWERTZ-LUX 303.08     10.5%

How much better is it?

Using this effort model (with the weights shown above), you can see how the layouts compare:

Visualizing the difference: heat maps

Heat maps show where your fingers spend time. Brighter colors = more keystrokes. Ideally, you want the brightness to be concentrated on the home row.

Notice how BÉPO and QWERTZ-LUX concentrate activity on the home row, while QWERTZ distributes effort across all rows.

What’s next?

That’s why I’d like to know what others think. Is this something you would like to explore further? The next step would be to write one layout.ini file for Portable keyboard layout for Windows, and write layout files for Linux and macOS, and let real people test it in real settings. We can see if it feels good and what else can be optimized.

But is there any chance that such a layout will ever be adopted? After all, there are obstacles:

• People just don’t care and will never switch
• Even if people care, Luxembourg is too small a market and keyboards will never come with a Luxembourg specific layout

In my opinion, rolling out such a keyboard would require a phased and gradual approach:

• Let children learn to type at school with the optimized layout
• Distribute keyboard layout stickers, which are cheap

After a few years the transition would be complete, so I think it is feasible, but only if there is a community around this layout. And who knows, this layout could technically be adopted in Switzerland and other German-speaking countries (perhaps as a variant without direct access to French-accented letters).

About the name

The current working name “QWERTZ-LUX” is descriptive but not definitive. The first letters of the layout are QWFOGthat doesn’t exactly roll off the tongue like ‘QWERTY’ or ‘BÉPO’. Here are some alternatives I am considering:

What do you think? I am sincerely open to suggestions: a good name helps with adoption!

Oh, and Happy New Year I guess.