ci: unify/simplify documentation and ci nix steps

Signed-off-by: strawberry <strawberry@puppygock.gay>

.github/workflows/ci.yml

@@ -64,6 +64,9 @@ jobs:
 
             - name: Install Nix
               uses: DeterminateSystems/nix-installer-action@main
+              with:
+                diagnostic-endpoint: ""
+                extra-conf: "experimental-features = nix-command flakes"
 
             - name: Enable Cachix binary cache
               run: |

.github/workflows/documentation.yml

@@ -31,7 +31,6 @@ concurrency:
 jobs:
   docs:
     name: Documentation and GitHub Pages
-
     runs-on: ubuntu-latest
 
     permissions:
@@ -50,52 +49,49 @@ jobs:
         if: github.event_name != 'pull_request'
         uses: actions/configure-pages@v5
 
-      - name: Install Nix (with flakes and nix-command enabled)
-        uses: cachix/install-nix-action@v27
+      - name: Install Nix
+        uses: DeterminateSystems/nix-installer-action@main
         with:
-          nix_path: nixpkgs=channel:nixos-unstable
+          diagnostic-endpoint: ""
+          extra-conf: "experimental-features = nix-command flakes"
 
-          # Add `nix-community`, Crane, upstream Conduit, and conduwuit binary caches
-          extra_nix_config: |
-            experimental-features = nix-command flakes
-            extra-substituters = https://nix-community.cachix.org
-            extra-trusted-public-keys = nix-community.cachix.org-1:mB9FSh9qf2dCimDSUo8Zy7bkq5CX+/rkCWyvRCYg3Fs=
-            extra-substituters = https://crane.cachix.org
-            extra-trusted-public-keys = crane.cachix.org-1:8Scfpmn9w+hGdXH/Q9tTLiYAE/2dnJYRJP7kl80GuRk=
-            extra-substituters = https://attic.kennel.juneis.dog/conduit
-            extra-trusted-public-keys = conduit:eEKoUwlQGDdYmAI/Q/0slVlegqh/QmAvQd7HBSm21Wk=
-            extra-substituters = https://attic.kennel.juneis.dog/conduwuit
-            extra-trusted-public-keys = conduwuit:BbycGUgTISsltcmH0qNjFR9dbrQNYgdIAcmViSGoVTE=
-
-      - name: Add alternative Nix binary caches if specified
-        if: ${{ (env.ATTIC_ENDPOINT != '') && (env.ATTIC_PUBLIC_KEY != '') }}
+      - name: Enable Cachix binary cache
         run: |
-          echo "extra-substituters = ${{ env.ATTIC_ENDPOINT }}" >> /etc/nix/nix.conf
-          echo "extra-trusted-public-keys = ${{ env.ATTIC_PUBLIC_KEY }}" >> /etc/nix/nix.conf
+            nix profile install nixpkgs#cachix
+            cachix use crane
+            cachix use nix-community
 
-      - name: Pop/push Magic Nix Cache
+      - name: Configure Magic Nix Cache
         uses: DeterminateSystems/magic-nix-cache-action@main
         with:
           diagnostic-endpoint: ""
           upstream-cache: "https://attic.kennel.juneis.dog"
 
-      - name: Configure `nix-direnv`
+      - name: Apply Nix binary cache configuration
         run: |
-          echo 'source $HOME/.nix-profile/share/nix-direnv/direnvrc' > "$HOME/.direnvrc"
+            sudo tee -a /etc/nix/nix.conf > /dev/null <<EOF
+            extra-substituters = https://attic.kennel.juneis.dog/conduihttps://attic.kennel.juneis.dog/conduwuit https://cache.lix.systems
+            extra-trusted-public-keys = conduit:eEKoUwlQGDdYmAI/Q/0slVlegqh/QmAvQd7HBSm21Wkconduwuit:BbycGUgTISsltcmH0qNjFR9dbrQNYgdIAcmViSGoVTEcache.lix.systems:aBnZUw8zA7H35Cz2RyKFVs3H4PlGTLawyY5KRbvJR8o=
+            EOF
 
-      - name: Install `direnv` and `nix-direnv`
-        run: nix-env -f "<nixpkgs>" -iA direnv -iA nix-direnv
+      - name: Use alternative Nix binary caches if specified
+        if: ${{ (env.ATTIC_ENDPOINT != '') && (env.ATTIC_PUBLIC_KEY != '') }}
+        run: |
+            sudo tee -a /etc/nix/nix.conf > /dev/null <<EOF
+            extra-substituters = ${{ env.ATTIC_ENDPOINT }}
+            extra-trusted-public-keys = ${{ env.ATTIC_PUBLIC_KEY }}
+            EOF
 
-      # Do this to shorten the logs for the real CI step
-      - name: Populate `/nix/store`
-        run: nix develop --command true
-
-      - name: Allow direnv
-        run: direnv allow
+      - name: Prepare build environment
+        run: |
+            echo 'source $HOME/.nix-profile/share/nix-direnv/direnvrc' > "$HOME/.direnvrc"
+            nix profile install --impure --inputs-from . nixpkgs#direnv nixpkgs#nix-direnv
+            direnv allow
+            nix develop --command true
 
       - name: Cache CI dependencies
         run: |
-          ./bin/nix-build-and-cache ci
+            bin/nix-build-and-cache ci
 
       - name: Build documentation (book)
         run: |