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-# manifold
+# Manifold Markets
 
-Manifold Markets
+## Directory overview
+
+- `web/`: UI and biz logic. Where most of the site lives
+- `functions/`: Firebase cloud functions, for secure work (balances, Stripe payments, emails)
+- `common/`: shared between web & functions
+- `og-image/`: The OpenGraph image generator; creates the preview images shown on Twitter/social media
+
+## Philosophies
+
+- [JAMStack](https://jamstack.org/): Keep things simple, no servers
+- [Monorepo](https://semaphoreci.com/blog/what-is-monorepo): Good fit for our current size
+- [Small PRs](https://google.github.io/eng-practices/review/developer/small-cls.html): Lots of little changes > one big diff