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This slightly understated image, taken around dusk, is one of my favourites from my trip to Egypt last year. At first glance it’s just a sunset taken over a “generic” city, but a more comprehensive look reveals the pyramids, meaning that it must be Cairo.

Please also vote for my entry in last weeks challenge, “Black.” I’m entry number 226.

You may have noticed that ZX81.org.uk has been offline for at least twenty-fours hours. I don’t know exactly how long, but I first noticed about this time yesterday.

At the moment I have no idea what happened. The company hosting the site have not been terribly forthcoming — no response to the support tickets I raised, no public announcement of the down time — which in a sense is even more disappointing that the downtime. No system is 100% reliable, but you should at least communicate with those most affected.

I am considering whether to move to a different provider (recommendations encouraged), but in the meantime I am hoping that things have returned to normal.

What do Britney Spears and Yummy, my iPhone Delicious.com client, have in common? If you had asked me a few months ago I would have said nothing but I’d have been wrong. No, they both have had to grow up in public.

For a version 1.0 product, Yummy seemed solid to me. It was fast, coped will all my bookmarks and had the ability to add, edit and delete entries. I didn’t think that this would remain as a unique feature for as long as it has, but hey, that’s a bonus.

Within a few days I had exceeded what I had expected to sell and received positive feedback on the iTunes store. But not long after that I also received my first bug report.

This turned out to be an odd one. It crashed early on while starting up and downloading all the bookmarks for the first time. My first guess — incorrect as it turned out — was that it was running out of memory. It took some investigation with the help of a very kind end-user to discover that… Delicious allows technically invalid URLs. By that I mean both that they don’t follow web standards and, worse, that it’s not even possible to open them in Mobile Safari.

I don’t feel so bad about not spotting that one during testing, although I should have put in more error handling to spot various “impossible” events and make sure that it didn’t crash. The reason I mention it is to give an idea of the kind of things that happen in “real life.”

But my biggest mistake has been assuming that I am a typical user of Delicious. I thought a few hundred bookmarks was a lot but I now realise that I was wrong. I have some users with over a thousand bookmarks and have read about another with nearly ten times that¹.

The exact number of bookmarks that you can store depends on a number of variables, such as the length of the URL, title and notes, the number of tags, the iPhone operating system² and a bunch of other details outside my control. Looking at the reviews on iTunes I believe a few people had more than whatever that limit is. Unfortunately the error handling was lacking, resulting in Yummy crashing rather than an inconvenient but understandable error message³.

Version 1.0.2 was actually a big release in terms of the amount of code changed, if not in terms of visible functionality (which is why it was such a small change in the version number). Under the hood, though, I dramatically increased the number of bookmarks that Yummy could handle. However it was starting to become clear that the internal architecture was holding me back. Further increasing the number of usable bookmarks would be hard, if not impossible, without seriously degrading performance and some new features that I wanted to add would end up in a nasty tangle of unmaintainable code.

I decided to take a step back and fix the structure of the code. For much of the time since the last formal release, Yummy has been, metaphorically speaking, in pieces on the floor. Most of those pieces have now been polished and reassembled, and it’s now working well enough that I have replaced the copy of 1.0.2 that I have been using day-to-day on my own iPhone with the development version.

This is a long way of saying that there is a new version coming. There will be a number of great new features but many of the big changes are behind the scenes. I sincerely hope that you don’t notice them.

1. I confess to being a little sceptical about some claims. At some points it becomes a bit of a pissing competition.↩
2. Upgrading from version 2.0 to 2.1 tipped at least one user over the edge, and many developers do not get previews of new versions.↩
3. I’ve not got to the bottom of this one yet. It seems that, sometimes, you can only spot a bad memory allocation by noting that an otherwise mandatory field is missing.↩

• Educated Catholics have sown dissent and confusion in the Church, claims bishop - A Catholic Bishop thinks that "mass education has led to 'sickness in the Church and wider society'." While teaching people to think for themselves may be a bad thing for the church I have a hard time seeing it as a bad thing for society as a whole.
• What you need to know about ID cards - "If you've done nothing wrong you've got nothing to fear. If you've something to hide you shouldn't even be here." ID cards just get worse the more you learn about them.
• Cameron anger at 'Stalinesque' arrest of Tory MP in leak inquiry - News so shocking that I actually agree with a Tory: "In a democracy, opposition politicians have a duty to hold the government to account. I was elected to the House of Commons precisely to do that and I certainly intend to continue doing so."

Photography is all about light, which makes this weeks PhotoFriday challenge rather challenging, “Black” being the absence of light. The best I’ve been able to do is this silhouette picture, taken in Oslo, Norway.

There’s a story about this image. I went to Norway shortly after buying my first SLR and, since I knew that I was going to be there for a while, decided to experiment with a few different kinds of film (this being Ilford XP2). I thought the contrast here worked well and was pretty pleased with the result.

I showed it to a colleague who asked whether I got the idea from the “Lonely Planet” guide. I hadn’t, but he was right. On the article about Vigland Park was an almost identical image.

Please also vote for my entry in last weeks challenge, “Food.” I’m entry number 84.

• WordPress 2.6.5 - As always: new version of Wordpress installed on zx81.org.uk, no known problems but please let me know if you find anything recently broken.
• The pitfalls of Africa's aid addiction - Interesting take on how Western aid to Africa isn't having the effect it's supposed to.
• How to Price Your iPhone App out of Existence - Nice analysis of the current iPhone application pricing situation. Summary: not good for the long term.