diff --git a/bathroom-review-platform/README.md b/bathroom-review-platform/README.md
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+# bathroom-review-platform
+
+a review platform for bathrooms- aimed at people with sensitive stomachs who actually need to know what they're walking into before they walk in.
+
+sounds like a joke, and honestly it kind of is, but it also genuinely makes sense when you think about it.
+
+## sections
+
+the design document is broken down into these parts:
+
+- [why i thought of this idea](./why.mdx) - the origin story behind this, what made me think about it
+- [the problem](./problem.mdx) - the actual problem, backed with some numbers
+- [solution & requirements](./solution.mdx) - what the solution looks like and the requirements
+- [references](./references.mdx) - links and resources that were used or referenced
+- [raw inputs](./raw.mdx) - the unedited inputs that were used to put this together, for transparency
diff --git a/bathroom-review-platform/problem.mdx b/bathroom-review-platform/problem.mdx
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+# the problem
+
+there's a surprisingly large number of people who deal with sensitive stomachs and digestive issues- and there's basically no good way for them to find a clean, reliable bathroom when they need one.
+
+## the numbers
+
+according to a [meta-analysis published in clinical gastroenterology and hepatology](https://doi.org/10.1016/j.cgh.2012.02.029), roughly 11.2% of the global population suffers from irritable bowel syndrome (ibs) alone. that's about 1 in 9 people.
+
+and that's just diagnosed ibs- a broader study by the [rome foundation published in gastroenterology](https://doi.org/10.1053/j.gastro.2020.04.014) found that around 40% of people worldwide experience some form of functional gastrointestinal disorder.
+
+## so what's the actual problem?
+
+when you have a sensitive stomach, finding a usable bathroom isn't a luxury- it's a necessity. and right now there's no reliable way to know what you're walking into. google reviews might mention a bathroom in passing, but there's no dedicated system for it. no ratings, no photos, no actual information about the thing that matters when you really need it.
+
+it's a weirdly overlooked gap- a huge chunk of the population deals with this, and the best they can do is hope for the best.
diff --git a/bathroom-review-platform/raw.mdx b/bathroom-review-platform/raw.mdx
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+# raw inputs
+
+these are the raw unedited inputs that were provided to put together the design document- just for transparency and an open look at how the ideas were communicated before being cleaned up.
+
+---
+
+## initial idea
+
+ok so the idea is for a bathroom sort of a review platform, for people who have very sensitive stomachs, ik sounds dumb but honestly this is very useful, because people can review it, and all that, and send photos of the quality of it and all that, its a bit of a joke but also in a sense practically makes sense sicne there is a lot of people who have sensitive stomachs (find a metric), this is the general idea, only stick to what i said here an make it and put up a draft pr for now thanks!
diff --git a/bathroom-review-platform/references.mdx b/bathroom-review-platform/references.mdx
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+# references
+
+things that were used or referenced while putting this together.
+
+- [global prevalence of ibs - meta-analysis](https://doi.org/10.1016/j.cgh.2012.02.029) - lovell & ford, clinical gastroenterology and hepatology, 2012
+- [worldwide prevalence of functional gastrointestinal disorders - rome foundation](https://doi.org/10.1053/j.gastro.2020.04.014) - sperber et al., gastroenterology, 2021
diff --git a/bathroom-review-platform/solution.mdx b/bathroom-review-platform/solution.mdx
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+# solution & requirements
+
+a platform where people can review bathrooms- with ratings, photos, and details about the quality and cleanliness.
+
+## what it does
+
+users can:
+
+- review bathrooms at locations (restaurants, malls, public spaces, etc.)
+- upload photos of the bathroom quality
+- rate and leave details about cleanliness, accessibility, and overall state
+- browse and search for reviewed bathrooms near them
+
+## who it's for
+
+primarily people with sensitive stomachs or digestive issues who need to know what they're getting into- but honestly useful for anyone who's ever walked into a bathroom and immediately regretted it.
+
+## requirements
+
+these are the core things the platform needs to do:
+
+- users can submit reviews with ratings and photos
+- users can browse and search for bathrooms by location
+- reviews should cover things like cleanliness and general quality
+- photos should be supported so people can actually see what they're dealing with
+- location-based search so you can find reviewed bathrooms near you
+
+tbd- technical design, specific rating categories, moderation approach, and the rest of the details are still to be figured out.
diff --git a/bathroom-review-platform/why.mdx b/bathroom-review-platform/why.mdx
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+# why i thought of this idea
+
+honestly this one started as a bit of a joke- but the more you think about it, the more it actually makes sense.
+
+if you've ever had a sensitive stomach, you know the pain of walking into a bathroom that's just... not it. and there's no way to know beforehand. you're just gambling every time.
+
+so the idea is simple- a platform where people can review bathrooms. the quality, the cleanliness, photos and all that. it sounds dumb at first but for people who genuinely deal with stomach issues on a daily basis, having a reliable way to find a decent bathroom when you need one is actually kind of a big deal.
+
+it's one of those ideas that lives in the sweet spot between joke and genuinely practical.
diff --git a/index.mdx b/index.mdx
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+++ b/index.mdx
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 a collection of system design documents for random ideas that come to mind.
 
 - [tribal-knowledge-mcp](./tribal-knowledge-mcp) - making tribal knowledge queryable by ai agents through an mcp server
+- [bathroom-review-platform](./bathroom-review-platform) - a review platform for bathrooms, aimed at people with sensitive stomachs