Getting serious about serious games

Posted on Fri 24 October 2025 in Gamedev

Over time, I have developed a small portfolio of serious games. Let's make a list.

1. i18n-puzzles.com

i18n-puzzles.com is a serious game that teaches programmers how to deal with internationalization problems.

Internationalization (abbrivated as i18n) is the art of making software suitable for an international audience. You can think of translations, units & measurements, foreign characters, time zones, and so on. These things are often sources of frustration and causes of tricky bugs. I wanted to give programmers more confidence to deal with these topics. So I started creating programming puzzles, inspired by the Advent of Code.

Initially this was for an internal training at TOPdesk, but this turned out to be so much fun, that I decided to turn it into a public resource. In March 2025, I hosted an event where I published twenty puzzles, day after day. Up to 300 online participants competed to be the first to solve a puzzle each day.

Now I'm speaking about the whole project at developer conferences. Earlier I spoke at Devoxx Belgium 2025. You can watch the recording on Youtube:

In the coming weeks, I will be talking at two more conferences:

i18n-puzzles.com will remain publicly available in the future. And I have a "bonus pack" with extra puzzles in preparation, although I haven't committed to a deadline yet.

2. Food Chain Farm

Food Chain Farm is a serious game for the biology classroom, that explores the fundamental cycles of biology.

Biology can sometimes be abstract. Photosynthesis, respiration, the carbon cycle, the nitrogen cycle, these are unintuitive concepts. The idea behind Food Chain Farm is that with a visual, interactive simulation, it's all much easier to understand. The game is now regularly being used in the classroom.

Screenshot of Food Chain Farm

Food Chain Farm 0.7 is available right now. That version was released in 2023. I'm still planning to make a version 0.8, although admittedly progress has been slow while i18n-puzzles absorbed my attention.

3. TOPscape

TOPscape is a serious game designed to help a software company to adopt a new technology.

At TOPdesk, several teams develop one big application in parallel. Working together on a single product is not easy, it can lead to all kinds of bottlenecks and interdependencies. That is why we introduced Micro Frontends, a pattern in software architecture that helps to scale software development accross many teams.

To introduce this concept to the origanization, I planned a game (assisted by a group of summer interns). This game took place during a two-day hackathon. Pairs of programmers built puzzle screens, using the micro frontend concept. In the end, all the puzzles were wired together to form a single large escape room puzzle.

Screenshot of the main hallway that you have to escape.

We ended up with over a dozen puzzles, from many developers. It was a great way to get all developers acquainted with the concept. And the final game was a lot of fun to play.

I will present a 5-minute ignite session on this project on 6 November at J-Fall in Ede

4. Peppy Peptide puzzle

Peppy Peptide Puzzle is a serious game that teaches how DNA translates to proteins.

This game is a series of puzzles, where you have to mutate a DNA sequence in order to create the correct amino acid sequence. The core idea was inspired by the Amino Acid Card game by Helen Cook, which I encountered at a conference one time.

Screenshot of Peppy peptide puzzle.

Peppy Protein Puzzle is publicly available and ready to play.

5. DBA Detective

DBA Detective is a serious game that teaches you how to write database queries.

In this game, you join Detective Dick B. Anderson, in his forensic investigations to solve murders. Your job is to support him from behind the computer. You make use of the NYPD forensic database, which is filled with information about potential suspects, license plates of getaway vehicles, suspicious financial transactions, and more. All you have to do, is come up with the correct SELECT query, and the murderer rolls out automatically.

Intro paragraph of detective game, with illustration

The DBA Detective game is part of a training on database queries with SQL. There are several detective stories, each with another murder to solve, and more SQL concepts to learn. This is the first gamified workshop that I developed at TOPdesk, together with several colleagues. We ran the workshop half a dozen times, and received lots of positive feedback. It turns out that people find the story-driven approach really motivating.

Currently, this workshop is available only internally at TOPdesk. If you're interested, let me know. If there is demand for it, we could probably make it open source with some effort.

Conclusion

As you can see, I'm getting serious about serious games. I've had the chance to experiment with different target audiences and different game mechanics, from story driven games to puzzles to construction and simulation. They take a lot of work to implement properly, but the pay-off can be very satisfying, both in terms of fun and educational value.


Celebrating Food Chain Farm version 0.7

Posted on Mon 10 April 2023 in Gamedev

I just released version 0.7 of Food Chain Farm, my casual space ecosystem sim. Get it while its hot!

So let's talk about this release. What's new in this release? What have I learned along the way? And when will the game be finally done?

What's new?

It's fair to say that this is a pretty big release. I even took a 3-month sabbatical to work on the game.So what's new in Food Chain Farm 0.7?

image1

First of all, I've added a story. I wanted to motivate the player, to set a goal that you can engage with emotionally. So I've written some lore, and it goes as follows. You are Xlorp, a young alien boy, and you have to take care of a marooned interplanetary colonist, a rescued human. Being an alien, your biochemistry is very different from humans, and therefore you have to figure out everything from scratch. You have to build a supporting ecosystem. You'll start to grow some plants to generate oxygen, and some simple vegetables as food. Over time you learn to make better and more tasty food, and improve life quality for your human pet.

image2

Secondly, I wanted to some sort of progression system in the game, a way to upgrade your systems and unlock new possibilities over time. So I've added this in the form of the pet store. Zed, the store owner, advices you on how to best take care of your human. If Zed sees that your human is doing well and you can handle the responsibility, then he will sell you some useful pet care amenities. Perhaps some livestock, or some kitchen appliances to produce better quality food. Zed is a helpful and knowledgeable being that really supports you while you're trying to figure things out.

For the third addition, we have to dive more deeply into the science. I wanted to make the game system more complex, so there is more to explore and discover. Previous editions of food chain farm have focused only on the carbon cycle, now I've also added a nitrogen cycle. Nitrogen is an important compound for life, no living cell can be made without it. Nitrogen is all around us - the air we breathe is almost 80% Nitrogen. Yet most of this nitrogen is not in a form that plants can consume. Dealing with that is an interesting challenge.

image3

Outgrowing the classroom

So just a bit of background: I started work on Food Chain Farm a few years ago, in collaboration with my sister who teaches biology in high school. At the time, my goal was to create a game to teach biological concepts in a fun and visually interesting way. Carbon cycle, photosynthesis, food chains, all of that can be quite abstract sometimes, but I wanted to make it really come to life. This has been quite successful. The game has been used in classrooms over half a dozen times, and another classroom session on the nitrogen cycle is on the schedule. (If you're a teacher reading this and you want to try it in your classroom, contact me).

But, I've come to realize something about games for the classroom. They can get away with being less fun, because:

  1. You have a captive audience.
  2. "More fun than regular class" is a low bar. Students appreciate anything that breaks the rut.
  3. The game needs to be entertaining for only one hour. By contrast, a store-bought game needs to be entertaining for a dozen hours, to feel like you got your money's worth.

And that is also why the label "Educational game" has so many negative connotations. Marketing is very different for educational games. Educational games are sold to teachers and parents. They need to showcase educational value. The kids, who get these "fun" games hoisted upon them, learn to associate "educational game" with "boring, forced experience". In other words, if you target parents and teachers, educational is good. If you target gamers, educational is best left out.

And here's the rub. I'm gamer at heart and it stings to think people will think less of Food Chain Farm due to the educational label. I want to prove that games can be both fun and educational at the same time. That the educational aspects of a game don't make it less fun. And the only way to prove that, actually prove that, is to make a commercially viable game - competing in the real world against games that are definitely fun.

So, no more "educational", at least not in the marketing materials. Instead, I'm going with the phrase "science-based game". It's a real game, designed for having fun. However, grounded in science. Like my favorite book, "The Martian", by Andy Weir. This book is, at the highest level, a gripping tale of perseverance and inventiveness in the face of almost certain doom. If you come away learning something about how to grow potatoes on mars using rocket fuel, then all the better, but that's really just a side-effect. I've not "given up" on making games for the classroom. But I realize that I can't be sure that the game is fun, unless I can also sell it as a regular game.

Future plans

Let's be clear here - the game is not done! What we have at the moment, you may call an "Early Access Demo". I'm releasing as a way to gauge reactions, and to show my plans. But there are definitely rough edges, and I have so many ideas for improvements. Here are some ideas I'm considering for a future update:

  • Saving and loading. Currently there is no way to save progress, if you close the game you have to start over. This is something I intend to fix.
  • Bio-plastics for building pipes and tubes (you no longer get them for free)
  • Blowing up asteroids with explosives to get extra resources and discover secrets. Many explosives are based on nitrate, which ties nicely into the nitrogen cycle.

What else should I add? Let me know! And if you want to stay updated on future releases, subscribe to the newsletter or join us on Discord!


Developing an art style for food chain farm

Posted on Sun 15 November 2020 in Gamedev • Tagged with Art, Food Chain Farm

Just a couple of weeks ago I released version 0.5 of Food Chain Farm! This release has been a year in the making and has a ton of new stuff. Today, I want to dive deeper into one aspect: the improved art style.

The game has a lot of graphics, more than any other game I've done before. Dozens of plants, animals, resources and other objects, all drawn in detailed vector graphics. And it's a huge challenge for me. I've always been programmer first, graphical artist second (and music is even further down the list...). For most games I worked on in the past, I've either limited myself to a small amount of pixel art, or I've outsourced the artwork to a partner. They say you need to put in 10000 hours to become really good, and I'm afraid I haven't put those hours in yet...

And there are so many beautiful indie games out there. It's hard not to feel discouraged when there are so much awesomeness to compare with. Nevertheless, I'm going to stick with it. I'll be the first to admit that this art style is a work in progress. But with the 0.5 release, for the first time I'm happy with the direction things are going.

As an example, let's look at how one item in the game has evolved over the past years:

apple tree original

The apple tree has been in the game right from release 0.1, back in 2018, and I put it together quickly in Inkscape, from basic geometric shapes. The foliage is just the union of bunch of circles, the trunk was drawn as a polygon using the mouse. Inkscape makes it easy to adjust the curve of a given line, so I made the sides of the stem curve inwards. The apple itself is a modified circle, with a green-red-white radial gradient to give it a nice shine. I added a short brown line for the stem of the fruit. To top it all off I gave the foliage a gradient as well, as a cheap way to give it some highlights and shadow.

This was always meant to be a placeholder, to get going quickly - it was never the intention that this would make it into the final game. But coming up with a better version took longer than I thought.

I've experimented with various methods e.g. using a Wacom tablet, using the 'trace sketch' function in Inkscape, with mixed results. In the end I settled on a much simpler process: I first sketch on paper, I scan it, and then trace the sketch with the mouse, in Inkscape. The result looks like this.

apple tree sketch and final image

For inspiration and examples, I use images from the internet of course. But in this case I could actually take inspiration directly from my environment. I live next to a small orchard, and there is this nice old apple tree right in front of my house. The trees tend to be pruned to a flat wide shape (I guess it's easier to pick apples that way) and end up with crooked, gnarly looking branches. It's something that I tried to mimic in this sketch.

photo of apple tree

The sketching phase is important. I've learned that I'm much better at coming up with ideas on paper first. Sketching digitally doesn't work well for me. And over time, my sketches have developed in a certain way. I'm making them more elaborate, trying to add more character, but at the same time I make them looser, more playful. I spend less effort making the sketches very precise. I don't worry about the exact lines until I digitize the sketch in Inkscape.

To see what I mean, take a look at this bunny character. I started with a few quick sketches. These were drawn after photos and have realistic proportions.

rabbit sketches

Compared to, say, a cow or a pig, bunnies have a relatively small, narrow face. And, of course, large ears. By giving the head a more exaggerated shape, narrow at the eye level, and oversized ears, the essence of the character becomes more rabbity. I switched to a frontal perspective, this is a common theme for all animals in the game.

image1I've tried to become less rigid, using more round curves instead of straight lines, even for things that ought to be straight. Take a look at the new oven drawing for example. Here I exaggerated the roundness of the countertop and the brick sides.

oven sketch and final image

Below you see some sources of inspiration. The picture on the left is from Anton Pieck. This Dutch artist is known for a romantic style, with old fashioned candy shops, life-worn houses and snow-covered Christmas villages. His paintings put a lot of detail in building materials, making them atmospheric and full of character. I grew up with this art style - he was the original designer for the Efteling theme park, where I visited frequently as a kid. The image on the right is from the game Oxygen Not Included (ONI). I love this game for the art style. Everything is full of character. Ladders, pipes, walls and floors - things that really should be straight - are higgledy-piggledy. ONI takes creative liberties to give it a unique character. By the way, ONI has more things in common with Food Chain Farm - more on that in a later post.

inspirations

Also, to get more practice (to get those 10000 hours if you will), I've been  taking some live model drawing classes. The pictures below were taken during a socially distanced drawing class this summer. Drawing live models is great sketching practice. You have to be quick - the model can hold a pose only for so long. One common warm-up exercise is to draw a succession of poses in two minutes. It seems impossible at first, but you really get better with practice.

Photo of drawing class

Of course, for the game, I can change proportions for a more cartoony appearance. Here are some sketches I'm working on, for a future version of the game.

Have a look for yourself, Food Chain Farm 0.5 can be downloaded from itch.io!


Bringing Food Chain Farm to the classroom

Posted on Thu 17 January 2019 in Gamedev • Tagged with Classroom, Educational Games, Food Chain Farm

We tested Food Chain Farm for the 3rd time in a classroom setting, with great results. So, how does that actually work in practice?

We use a modified version of the game. The first three "levels" are really just simulations. Students have to watch clouds of oxygen and carbon dioxide move between farm animals and answer about 20 questions on paper. Starting with a questionnaire might seem like a boring way to present a game, but it works well. Not all students are natural gamers, and this way they can think about biology before they have to think about which buttons to click.

The first few questions are extremely simple and are designed to make the students just observe what is happening on the screen:

Question: Which two resources are produced by the tree? (Answer: Oxygen and Apples)

Further on, it gets a bit tougher and students are supposed to link what they see with what they've learned before.

Question: Which process takes place in the tree (Answer: Photosynthesis)

Question: which cycle is simulated in this game. The carbon cycle, or the nitrogen cycle? (Answer: the carbon cycle)

But then we get to the more interesting part. Further questions do not have a single simple answer. They are designed to make the students think critically, and are a great starting point for classroom discussion.

Question: the tree converts inorganic substances into food, which the cow consumes and converts again into milk and inorganic substances. However after a while, the truck is full of milk and the cycle stops. Why does it stop? (Answer: If milk stays in the truck, then resources are taken away from the cycle. The cycle is actually incomplete, and must break down eventually)

After the questionnaire is done (after half an hour), students are free to play the regular game as far as they can get. They continue to play and build at their own pace. For an extra challenge, all scores are tracked and projected on a central screen.

This is a game is about concepts like photosynthesis, carbon cycle, trophic levels,  producers, consumers, herbivores, carnivores, assimilation, dissimilation, food, and energy. But the game doesn't explain these concepts. I wouldn't recommend giving the game to new arrivals without instruction, and expect them to be able to take a biology test afterwards. What the game does do very well however, is use what was already taught, and reinforce it, visualize it, provide a fresh perspective on it. The novel presentation keeps students engaged.

I'm looking for more volunteers to test the game in a biology classroom. After three tries I'm very confident that I can provide something that is both engaging and educational. The question list can be adjusted to the level of the students to a very large extent. If you are a biology teacher, or know one, please leave a comment or send me a tweet.

Do you just want to play the game? Food Chain Farm can be downloaded here. Version 0.2 is out now and 0.3 is coming soon!