Update nix documentation the README (#235)

CONTRIBUTING.adoc

@@ -14,90 +14,15 @@ If you _really_ cannot use Nix and still want to contribute to Marconi, then xre
 
 === Installing and setting up Nix
 
-This project uses Flakes, so you must have Nix version `>= 2.4` installed.
+This repository uses Nix to provide the development and build environment.
 
-Either upgrade or install https://nixos.org/[Nix] following the instructions on https://nixos.org/download.html[its website].
+For instructions on how to install and configure Nix (including how to enable access to our binary caches), refer to link:https://github.com/input-output-hk/iogx/blob/main/doc/nix-setup-guide.md[this document]. 
 
-On Linux this command should suffice: `sh <(curl -L https://nixos.org/nix/install) --daemon`
-
-=== How to get a shell environment with tools
-
-To enter the development shell run the following command in the root directory:
-
-`nix develop`
-
-If you receive this message:
-
-`error: experimental Nix feature 'nix-command' is disabled; use '--extra-experimental-features nix-command' to override`
-
-Then try this:
-
-`nix develop --extra-experimental-features 'nix-command flakes'`
-
-You may now choose to edit your `/etc/nix/nix.conf` (global) or `~/.config/nix/nix.conf` (you must be a https://nixos.org/nix/manual/#ssec-multi-user[trusted user] to do this) by appending the following line:
-
-`extra-experimental-features = nix-command flakes`
-
-If you do so you will be able to enter the development shell by running `nix develop`.
-
-If you are a VSCode user, you may want to start your development session by running:
-
-`nix develop --command code`
-
-If this is your first time running `nix develop`, you may be asked the following:
-```
-do you want to allow configuration setting 'allow-import-from-derivation' to be set to 'true' (y/N)? y
-do you want to permanently mark this value as trusted (y/N)? y
-```
-Please type `y` to this and all subsequent prompts to make life easy for yourself.
-
-IMPORTANT: *It is particularly important to accept the `extra-substituters` and `extra-trusted-public-keys` settings, which will grant access to our Nix binary cache.*
-
-At this point and if this is your first time running `nix develop` then Nix will download, build and install a copious amout of dependencies.
-
-It is not uncommon for this process to take a couple of hours and to write tens of GBs to the `/nix/store`.
-
-*Rest assured that this only happens the very first time you run `nix develop`.*
-
-However you should pay attention to the output of `nix develop`: if you notice that you are _building_ GHC, it is likely that your caches have not been configured correctly.
-
-Accepting the configuration settings as outlined above should be sufficient to avoid this, however if your caches are still broken, you may try to append the following lines to `/etc/nix/nix.conf` and/or `~/.config/nix/nix.conf`:
-
-----
-substituters = https://cache.iog.io https://cache.nixos.org/
-trusted-public-keys = hydra.iohk.io:f/Ea+s+dFdN+3Y/G+FDgSq+a5NEWhJGzdjvKNGv0/EQ= cache.nixos.org-1:6NCHdD59X431o0gWypbMrAURkbJ16ZPMQFGspcDShjY=
-extra-experimental-features = nix-command flakes
-----
-
-On NixOS, set the following NixOS options:
-----
-nix = {
-  binaryCaches          = [ "https://cache.iog.io" ];
-  binaryCachePublicKeys = [ "hydra.iohk.io:f/Ea+s+dFdN+3Y/G+FDgSq+a5NEWhJGzdjvKNGv0/EQ=" ];
-};
-----
-
-You will need to restart the nix-daemon on non-NixOS for the changes to take effect, or just restart your machine.
-
-IMPORTANT: If you are on NixOS or otherwise using a multi-user Nix install, you **must** be a trusted user to set substituters. If you are not a trusted user, enabling the options prompted by the flake will have no effect (non-trusted users are disallowed from doing this).
-
-On non-NixOS systems, add the following to the system-wide configuration (`/etc/nix/nix.conf`):
-
-```
-trusted-users = <username> root
-```
-
-You can also use a group name by prefixing it with `@`, e.g. to add all members of the `wheel` group:
-
-```
-trusted-users = @wheel root
-```
-
-On NixOS, add the user/group name to the list under [`nix.settings.trusted-users`](https://search.nixos.org/options?show=nix.settings.trusted-users).
+If you already have Nix installed and configured, you may enter the development shell by running `nix develop`.
 
 === Note on pre-commit hooks
 
-If you are committing code outside nix develop, you will get this error:
+If you are committing code outside `nix develop`, you will get this error:
 
 ----
 pre-commit not found. Did you forget to activate your virtualenv?

doc/read-the-docs-site/README.md

@@ -1,16 +1,18 @@
-# Plutus documentation site
+# Marconi documentation site
 
 This is a sphinx site.
 
 Run `nix develop` to enter a development shell with `sphinx-build` and `sphinx-autobuild`.
 
 The following commands are also available:
 
-- `build-readthedocs-site`
-  Build the docs locally in `_build/index.html`
-- `serve-readthedocs-site`
+- `develop-rtd-site`          
   Start a development server with live reload on `http://localhost:8000`
+- `build-rtd-site`             
+  Build the docs locally in `_build/index.html`
+- `serve-rtd-site`   
+  Build the full site with nix (including Haddock) and serve it on `http://localhost:8002`
 
-The doc site from main is built automatically and hosted [here](https://marconi.readthedocs.io).
+The doc site from main is built automatically and hosted [here](https://marconi.readthedocs.io/en/latest).
 
 Additionally, the site is built for all PRs, and a link to a preview can be found in the PR statuses.