Update Nix development and build guide (README.md)

nix/README.md

@@ -5,24 +5,14 @@ for developing, testing and building PostgREST.
 
 ## Getting started with Nix
 
-You'll need to [get Nix](https://nixos.org/download.html). The installer will
-create your Nix store in the `/nix/` directory, where all build artifacts and
-their dependencies will be stored. It will also link the Nix executables like
-`nix-env`, `nix-build` and `nix-shell` into your PATH. Nix will manage all
-other PostgREST dependencies from here on out. To clean up older build
-artifacts from the `/nix/store`, you can run `nix-collect-garbage`.
-
-If you are on a system that does not support nix, for example Windows, you can
-run the nix development environment in a docker container. Inside the `nix/`
-directory run `docker-compose run --rm nix` to start the docker container. This
-will set up the binary cache and launch `nix-shell` automatically.
+You'll need to [get Nix](https://nixos.org/download.html). Please follow the recommended installations from the official nix download website unless you know what you are doing.
 
 ## Building PostgREST
 
 To build PostgREST from your local checkout of the repository, run:
 
 ```bash
-nix-build --attr postgrestPackage
+$ nix-build --attr postgrestPackage
 
 ```
 
@@ -39,10 +29,10 @@ We recommend that you use the PostgREST binary cache on
 
 ```bash
 # Install cachix:
-nix-env -iA cachix -f https://cachix.org/api/v1/install
+$ nix-env -iA cachix -f https://cachix.org/api/v1/install
 
 # Set cachix up to use the PostgREST binary cache:
-cachix use postgrest
+$ cachix use postgrest
 
 ```