i built a swiss culture quiz. it ended up on national radio.

a friend once told me i'm the most bünzli person he knows. for the non-swiss: bünzli is Swiss German for that hyper-orderly, rule-obsessing, recycling-schedule-memorizing type of person. the kind who reports you for doing laundry on a sunday. the kind who shushes you at 10:01pm because quiet hours started one minute ago.

i took it as a compliment. then i built a quiz about it.

what's a bünzlimeter

bunzlimeter.ch measures how bünzli you are. answer questions about your relationship with recycling, your opinion on people who jaywalk, how you feel about trains running 2 minutes late — and it gives you a score.

simple concept. the kind of thing you build in a weekend and maybe your friends try it once.

except 10,000+ people took the quiz. and then SRF 3 called.

the SRF moment

SRF 3 is Swiss national radio. the kind of station your parents listen to on the drive to coop. and one day they featured the bünzlimeter on air.

i found out because my phone started buzzing with traffic notifications. the analytics dashboard looked like a hockey stick meme. people were sharing their results on social media, challenging their friends, arguing about whether zürich or bern is more bünzli.

i sat there watching the numbers climb thinking "this started as a joke at the dinner table."

the AI roasts

the quiz gives you a score. but the real feature is what happens after.

i built an AI character called the KI-Huuswart — AI Caretaker, basically the digital embodiment of that neighbor who watches everyone from behind their curtains. it takes your quiz results and generates a personalized roast. in Swiss German.

this was harder than it sounds. Swiss German isn't just German with an accent — it's a different beast entirely. getting an AI to generate text that actually sounds like a real swiss person talking (and not like a german tourist trying too hard) took a lot of prompt engineering and iteration.

under the hood it uses DeepSeek AI and Google Gemini. i built smart caching so the AI isn't generating fresh roasts for identical quiz profiles — that would burn through API credits faster than a bünzli burns through complaint letters.

the canton wars

i added a canton leaderboard almost as an afterthought. which canton has the highest average bünzli score?

this turned out to be the most engaging feature on the entire site. people started taking the quiz specifically to boost their canton's ranking. i saw spikes of traffic from specific regions as people shared it in local group chats. "zürich is losing to aargau, we need reinforcements."

regional pride is a powerful motivator. i didn't plan for it. the leaderboard was maybe 30 lines of code. but it turned a one-time quiz into something people came back to and shared competitively.

building it out

what started as a quiz page grew into a whole experience:

• canton leaderboard — the competitive element that kept people coming back
• achievement badges — because gamification works even on a joke quiz
• social sharing — optimized cards so your bünzli score looks good on instagram stories
• live zürich webcam — because what's more bünzli than watching a webcam of an intersection
• SBB train delay stats — real-time data on how late swiss trains are running (bünzlis care deeply about this)
• pedestrian crossing stats — yes, really
• bünzli TV — live streams of swiss parliament sessions
• swiss german glossary — for the confused non-swiss visitors who showed up after it went viral

i built it together with dreamlabs.ch. the tech stack is Next.js 15, React 19, TypeScript, Tailwind, Firebase/Firestore for the backend, Three.js for some 3D elements, Framer Motion for animations, and Chart.js for the leaderboard visualizations.

what 10,000 quiz takers taught me

low friction beats high complexity. the quiz takes 2 minutes. no sign-up. no email required. you click a link, answer questions, get roasted, share it. every step i removed from the flow increased completion rates.

humor is distribution. nobody shares a "personality assessment tool." everyone shares "lmao i got 87% bünzli." the entire growth strategy was: make something funny enough that people want to show their friends.

regional identity is underrated. the canton leaderboard wasn't a feature i agonized over. it was a throwaway addition. but it tapped into something real — people identify with where they're from, and they'll engage with content that lets them represent their region.

AI needs character, not just capability. the KI-Huuswart works because it has a personality. it's not "here's your AI-generated result." it's "your AI caretaker has reviewed your file and has concerns." the character makes the interaction memorable.

the honest take

the bünzlimeter taught me more about product design than any course i've taken. not because it's complex — it's not. but because it's the first thing i built where the growth was entirely organic. no ads. no SEO strategy. just people sharing something they thought was funny.

10,000+ quiz takers. SRF 3 national radio. canton-level rivalry. and it started because someone called me bünzli and i said "bet."

the whole thing is open source if you want to see how it works. or just go take the quiz at bunzlimeter.ch and find out how swiss you really are.

fair warning: the KI-Huuswart doesn't hold back.