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README.md

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+Gatekeeper - Door access system
+Status: WIP - not prod ready
+
+Dev with `nix develop`
+start dev server `uv run fastapi dev`
+Swagger UI @ http://127.0.0.1:8000/docs
+start prod server `uv run fastapi run`
+
+Issues:
+    `nix run` currently broken
+    timeslot not implemented
+    no auth
+    no door state
+    card system is dummy until I get hardware
+