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 # directed-complex
 
+## Working on this repo
+
+Use the `nix-shell` command to enter a development shell. Once in that shell use `ghcid` or `cabal repl`.
+
+## Background
 Inspired by [the topic of Amar's presentation](https://ncatlab.org/nlab/show/regular%20directed%20complex)
 
 ![Blackboard](./blackboard.png)