The inside story
The Debian birthday party was actually scheduled since the beginning of the DebConf15 planning. And we even found the band bellsparx to play for "free as in beer" to have a party, but nobody thought about a birthday cake.
Just four weeks before the start of the conference, the idea popped up in the weekly IRC meeting to get a birthday cake for the party. Originally Tassia suggested to bake a cake, which instantly got my support; I love cooking! But due to the food restrictions of the venue, access to their kitchen was denied. Instead the venue asked its primary bakery to deliver cake at about 1 EUR per piece, which was considered expensive. So Tassia and me started a private conversation after the official meeting and the secret cake team was formed.
Immediately after the meeting I started contacting bakeries to get better estimation of the costs for that amount of cake and - in parallel - contacted various schools and the VHS of Heidelberg (adult learning center) to ask for access to their kitchens. All of them declined access to the kitchens and the price tag of the bakeries was almost equal to the hostel's or even more expensive. Actually the price tag might not have been our primary concern, but the secret bake team wanted to have a baking event!
Still not giving up on the cake idea and without baking facilities available, we decided to "assemble" a cake. The initial plan was to use large pastry plates but we also found smaller ones in online shops, and so the idea was born to "paint" the Debian swirl in the size of 29x23 = 667 pastry pixels. From the available fruits we would end with red an yellow pixels - a little bit monochromatic, but definitely sufficient and with different tastes per color. Luckily, the nearest supermarket to the venue also had an online shop to check for ingredients. At the end we decided to manage the real planning on-site. Obviously the small, local supermarket wouldn't stock this amount of pastry plates (70 packages @ 6 pieces), but I was quite sure we would be able to order a few days in advance.
So Tassia, frolic and myself finally visited the supermarket on DebCamp's Tuesday. Three people running around with notebooks, talking just English and investigating products seemed very suspicious to the employees. But after a short conversation with them and a phone call to the supermarkets owner, we were able to order all ingredients (about 100kg) via email to be picked up on Saturday afternoon, if we send a mail until tomorrow morning. After deciding the final image, a rough calculation of ingredients (how many pieces of peach would be in can, how much curd creme - think cheese cake here - for 400 pixels, how much chocolate spread - vegan nougat was much too expensive, etc. ... just the pixel count was sure), the order was placed. We just needed two bowls, a can opener, an egg beater and ale-benches, which actually restricted the size of the "cake".
On Saturday, an hour before my talk, the ingredients and the tooling arrived. After robbing some ale-benches from the beer garden and simple assembling tests, I went for my talk, while the "always increasing" others continued the assembling of the pixels and "drawing" of the image. Not sure how many people joined in; and the lay-outing / out laying of pixels was a little bit hard, because our red and yellow pixels had slightly different sizes. So time passed quickly. The cake was scheduled for 21:30 and with the cloudy and windy weather it became apparent we were in need of additional light. We already had some additional lamps, but they were much too light for the wind. Luckily we had bought too much sand for the kids, so we were able to fix the lamps with the spare 10kg sand bags, but the wind prevented us from actually lighting the candles as planned.
So finally - at about 21:35 the one and only frame was rendered and ready to be eaten. The DPL had a small speech, Tassia informed the people of the eating scheme and the band started playing in the disco. The planning was just wrong in two regards: too much chocolate spread and curd, which would become integrated in our future meals. An hour later the last pixel was eaten.
Hope you all enjoyed the cake and the party!
On behalf and thanks to the small secret and large non-secret cake team,