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README.md

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+# 💩📈
+
+A better web UI for COVID wastewater data
+
+💩📈 is a simple web server that periodically downloads a data
+PDF from the Massachusetts Water Resources Authority, parses it to
+extract the data, and serves the data as CSV and JSON along with
+a simple Chart.js-based web frontend.
+
+## Environment variables
+
+- `CACHED_PDF_PATH`: file path to save the PDF to. Default: `./data.pdf`.
+- `STATIC_DIR`: directory containing static files to serve. Default: `./static/`.
+
+## Running
+
+### Nix Flakes
+
+```
+nix run git+https://git.xeno.science/xenofem/poop-graph?ref=main
+```
+
+(The Nix package is wrapped with `STATIC_DIR` set automatically to the
+correct Nix store path, so it'll serve the static files properly
+no matter what directory you run it from.)
+
+### Non-Nix
+
+```
+git clone https://git.xeno.science/xenofem/poop-graph
+cd poop-graph
+cargo run
+```
+
+## Other setup
+
+- 💩📈 serves HTTP on `127.0.0.1:8080`, and is meant to be used behind
+  a reverse proxy (e.g. Nginx), ideally with SSL certificates
+  (e.g. Let's Encrypt). If you prefer, you could also use that web
+  server to serve the static files, and only pass requests for
+  `/data.csv` and `/data.json` to 💩📈.
+- You'll probably want to set up a service (systemd or whatever your
+  OS uses) to start 💩📈 automatically with environment
+  variables set appropriately.