feat: new server to work as a nix cache

.gitlab-ci.yml

@@ -65,12 +65,18 @@ sync_repos:
   - mkdir -p ~/.ssh
   - chmod 700 ~/.ssh
 
+.scripts_cache: &scripts_cache
+  - nix --extra-experimental-features 'nix-command flakes'  profile install nixpkgs#attic-client
+  - attic login skynet https://nix-cache.skynet.ie/ $CACHE_KEY
+  - attic use skynet-cache
+
 # every commit on main will build and deploy
 .build_template: &builder
   tags:
     - nix
   before_script:
     - *scripts_base
+    - *scripts_cache
   rules:
     - changes:
       - applications/**/*
@@ -105,6 +111,7 @@ build:
   <<: *builder
   stage: test
   script:
+    - attic watch-store skynet-cache &
     - colmena build -v --on @active-dns
     - colmena build -v --on @active-core
     - colmena build -v --on @active