Computing Profession

The Citadel and the Amusement Park

Bertrand Meyer







Web sites, more precisely sites that provide their visitors with some interaction, come in two kinds: the citadel and the amusement park. There is very little in between.

Carcassonne ramparts









An amusement park coddles, pampers and tempts the visitor at every step. Are you having fun yet? Try this ride here! Special deal there at 10:30!

The defining concept of a citadel is impregnability. Every step must be hard. Every inch must be conquered. Failure is the norm, success the exception.

The most obvious examples of Web citadel are government sites. You hear a big fuss from politicians about digital access, then you try to do something online and find that the entire process is stacked against you.

The most obvious examples of Web amusement parks are successful e-commerce sites, where every feature is designed to make you feel good (and buy more).

Ease and hardship:

  • Amusement sites make difficult things simple. Ship products to a strange location; return a product; cancel a reservation. No problem, just click here!
  • Citadels make simple things complicated. Consider the “e-Visa” available from the government site of a country that shall remain nameless. (Forget that what you get is not a visa at all, just an invitation to pay an extra $75 and wait three-and-a-half hours at the arrival airport for the real visa.) You must upload a passport scan that is between 30Kb and 300Kb. Think of all the tool expertise it takes to convert a scan so that it will take less than 300Kb and still be readable (since it is all subject to post-processing and approval by a human).

Getting in:

  • Amusement parks remember you. When you come back, all your history, your tastes and the attempts that you did not complete are at your fingertips.
  • Citadels log you out if you have not been active for 10 minutes.


  • On amusement parks, things work.
  • On a citadel, you fill in a form for 20 minutes, only to get a 404 or  Server Error. Back to square one.


  • Amusement parks let you go smoothly from one function to the next.
  • Citadels force you to go back to the home page and peruse the Site Map (1994-style), which is not up to date anyway. Search, when present, is broken. 

Graphic design:

  • Most of the space in citadel sites is taken up by the large-font acronyms and logos of the organization. Their idea of user-friendliness is to include a PDF icon which you can click to learn that to read a PDF you can download Adobe Reader (for free!). Any useful information appears  in a little corner. Any action starts a new browser window.
  • Amusement park sites have a minimalist design and use close to 100% of the space for information, interaction  and enticement.


  • Amusement parks strive to provide you with the information you need at the time you need it.
  • Citadels are carefully plotted as obstacle courses. Not that they do not provide any information; that would be too simple. There is information galore, most of it entirely irrelevant, even excluding the endless legal notices and cookie warnings. I know at least two airline sites that on the home page generously offer a link to an Online Check-In page. Go there, and you find a long speech about all the advantages of online check-in (no need to stand in line at the airport! Oh, did you mention that you had luggage?) and grandiose speeches; that is to say, everything but a link to the page where you can actually check in online. (To find it, you have to use a search engine.)

The human touch:

  • Amusement parks automate most processes, but realize that sometimes you need to talk to someone. A few clicks and you get into a chat, or find a number to call, and the number answers. There is even the possibility to write (miracle!) an email, and (miracle!) someone will answer it the next day.
  • The people who commission citadel sites wake up at night sweating in terror: someone, somewhere, sometime might actually be able to reach the staff! They make sure such a catastrophe will never happen. The   Normal 0 false false false EN-US X-NONE X-NONE MicrosoftInternetExplorer4 “Contact Us Normal 0 false false false EN-US X-NONE X-NONE MicrosoftInternetExplorer4 link leads to a postal address in Kalamazoo. If there is a telephone number, you get put you on hold indefinitely.


  • Citadel sites are paranoid about security or, more often, security theater. You have to prove again and again who you are. Passwords must satisfy bizarre rules, specific to each site. You must change them every so often. The sites often disable browser capabilities to force you to re-enter your credentials each time.
  • Amusement parks address the security problem not by piling up requirements on users but by investing in infrastructure and fraud-detection technology. (At least one major e-commerce site does not require the CVC code on credit cards. As far as I know, they have never been hacked.)

What is most impressive about amusement park sites is the amount of technology, intelligence and plain care that goes into their design. Beyond the pleasure of using them to fulfill your purpose of the moment, however mundane, you feel the pleasure of witnessing the result of combining so many talents (whether exerted by individuals or combined by teams) in software construction, business savvy, graphic design, and psychology.

What is most surprising about citadel sites is to think of the software engineers. There must have been some, and whoever they are they must be members of the profession and share a few things with us. They must know what a hash table is, an l-value, an event loop. Wherever they studied, someone must have told them about UI design. And yet they produced this?

The world is not an amusement park, but it will be a better place the day we stop building citadels.

Photo credits:  Carcassonne (top left) by Pedro Nuno Caetano; Disneyland by occhietto

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