diff --git a/sys/srv/authelia/authelia-authrequest.conf b/sys/srv/authelia/authelia-authrequest.conf
new file mode 100644
index 0000000..858815e
--- /dev/null
+++ b/sys/srv/authelia/authelia-authrequest.conf
@@ -0,0 +1,32 @@
+## Send a subrequest to Authelia to verify if the user is authenticated and has permission to access the resource.
+auth_request /internal/authelia/authz;
+
+## Save the upstream metadata response headers from Authelia to variables.
+auth_request_set $user $upstream_http_remote_user;
+auth_request_set $groups $upstream_http_remote_groups;
+auth_request_set $name $upstream_http_remote_name;
+auth_request_set $email $upstream_http_remote_email;
+
+## Inject the metadata response headers from the variables into the request made to the backend.
+proxy_set_header Remote-User $user;
+proxy_set_header Remote-Groups $groups;
+proxy_set_header Remote-Email $email;
+proxy_set_header Remote-Name $name;
+
+## Configure the redirection when the authz failure occurs. Lines starting with 'Modern Method' and 'Legacy Method'
+## should be commented / uncommented as pairs. The modern method uses the session cookies configuration's authelia_url
+## value to determine the redirection URL here. It's much simpler and compatible with the mutli-cookie domain easily.
+
+## Modern Method: Set the $redirection_url to the Location header of the response to the Authz endpoint.
+auth_request_set $redirection_url $upstream_http_location;
+
+## Modern Method: When there is a 401 response code from the authz endpoint redirect to the $redirection_url.
+error_page 401 =302 $redirection_url;
+
+## Legacy Method: Set $target_url to the original requested URL.
+## This requires http_set_misc module, replace 'set_escape_uri' with 'set' if you don't have this module.
+# set_escape_uri $target_url $scheme://$http_host$request_uri;
+
+## Legacy Method: When there is a 401 response code from the authz endpoint redirect to the portal with the 'rd'
+## URL parameter set to $target_url. This requires users update 'auth.posixlycorrect.com/' with their external authelia URL.
+# error_page 401 =302 https://auth.posixlycorrect.com/?rd=$target_url;
\ No newline at end of file
diff --git a/sys/srv/authelia/authelia-location.conf b/sys/srv/authelia/authelia-location.conf
new file mode 100644
index 0000000..e8052c4
--- /dev/null
+++ b/sys/srv/authelia/authelia-location.conf
@@ -0,0 +1,20 @@
+## Virtual endpoint created by nginx to forward auth requests.
+location /internal/authelia/authz {
+    ## Essential Proxy Configuration
+    internal;
+    proxy_pass http://localhost:9091/api/authz/auth-request;
+
+    ## Headers
+    ## The headers starting with X-* are required.
+    proxy_set_header X-Original-Method $request_method;
+    proxy_set_header X-Original-URL $scheme://$http_host$request_uri;
+    proxy_set_header X-Forwarded-For $remote_addr;
+    proxy_set_header Content-Length "";
+    proxy_set_header Connection "";
+
+    ## Basic Proxy Configuration
+    proxy_pass_request_body off;
+
+    ## Advanced Proxy Configuration TODO: maybe reducir estos timeouts?
+    send_timeout 5m;
+}
\ No newline at end of file
diff --git a/sys/srv/authelia/default.nix b/sys/srv/authelia/default.nix
new file mode 100644
index 0000000..f30386e
--- /dev/null
+++ b/sys/srv/authelia/default.nix
@@ -0,0 +1,169 @@
+{
+  lib,
+  pkgs,
+  ...
+}:
+with lib; {
+  options = {
+    services.nginx.virtualHosts = mkOption {
+      type = with lib.types;
+        attrsOf (
+          submodule
+          (
+            {config, ...}: {
+              options = {
+                enableAuthelia = mkOption {
+                  default = false;
+                  type = bool;
+                };
+              };
+              config = mkIf config.enableAuthelia {
+                extraConfig = ''
+                  include ${./authelia-authrequest.conf};
+                  include ${./authelia-location.conf};
+                '';
+              };
+            }
+          )
+        );
+    };
+  };
+
+  config = {
+    systemd.services.authelia-main.before = ["nginx.service"];
+
+    services = {
+      nginx = {
+        recommendedProxySettings = true;
+        recommendedTlsSettings = true;
+        commonHttpConfig = ''
+          ## Headers
+          proxy_set_header X-Original-URL $scheme://$http_host$request_uri;
+          proxy_set_header X-Forwarded-URI $request_uri;
+          proxy_set_header X-Forwarded-Ssl on;
+
+          ## Basic Proxy Configuration
+          client_body_buffer_size 128k;
+          proxy_next_upstream error timeout invalid_header http_500 http_502 http_503; ## Timeout if the real server is dead.
+          # proxy_redirect  http://  $scheme://;
+          proxy_cache_bypass $cookie_session;
+          proxy_no_cache $cookie_session;
+          proxy_buffers 64 256k;
+
+          ## Trusted Proxies Configuration
+          ## Please read the following documentation before configuring this:
+          ##     https://www.authelia.com/integration/proxies/nginx/#trusted-proxies
+          # set_real_ip_from 10.0.0.0/8;
+          # set_real_ip_from 172.16.0.0/12;
+          # set_real_ip_from 192.168.0.0/16;
+          # set_real_ip_from fc00::/7;
+          real_ip_header X-Forwarded-For;
+          real_ip_recursive on;
+        '';
+        virtualHosts."auth.posixlycorrect.com" = {
+          enableACME = true;
+          forceSSL = true;
+          locations = {
+            "/" = {
+              proxyPass = "http://localhost:9091"; #TODO: hacer que eso esté en alguna config o en algún let
+            };
+            "= /api/verify" = {
+              proxyPass = "http://localhost:9091";
+            };
+            "= /api/authz/" = {
+              proxyPass = "http://localhost:9091";
+            };
+          };
+        };
+      };
+
+      authelia.instances.main = {
+        enable = true;
+        package = pkgs.unstable.authelia;
+        # config based on https://github.com/authelia/authelia/blob/master/config.template.yml
+        secrets = {
+          jwtSecretFile = "/var/trust/authelia-main/jwt-secret";
+          storageEncryptionKeyFile = "/var/trust/authelia-main/storage-encryption-file";
+          sessionSecretFile = "/var/trust/authelia-main/session-secret-file";
+        };
+        settings = {
+          theme = "dark";
+          default_2fa_method = "totp";
+          server = {
+            disable_healthcheck = true;
+            port = 9091;
+            host = "localhost";
+            endpoints.authz.auth-request.implementation = "AuthRequest";
+          };
+          # tls settings not modified https://github.com/authelia/authelia/blob/master/config.template.yml#L53
+          log = {
+            level = "info";
+            format = "text";
+          };
+          telemetry.metrics.enabled = false;
+          totp = {
+            disable = false;
+            issuer = "https://getaegis.app/ or whatever you prefer";
+          };
+          webauthn = {
+            disable = false;
+          };
+          duo_api.disable = true;
+          authentication_backend.file = {
+            path = "/var/lib/authelia-main/users_database.yml";
+            password.algorithm = "argon2";
+          };
+          password_policy.zxcvbn = {
+            enabled = true;
+            min_score = 3;
+          };
+          access_control = {
+            default_policy = "deny";
+            rules = [
+              {
+                domain = "auth.posixlycorrect.com";
+                policy = "bypass";
+              }
+              {
+                domain = "meet.posixlycorrect.com";
+                policy = "bypass";
+              }
+            ];
+          };
+          session = {
+            name = "posixlycorrect_session";
+            same_site = "lax";
+            inactivity = "5m";
+            expiration = "1h";
+            remember_me = "1M";
+            cookies = [
+              {
+                name = "posixlycorrect_session";
+                domain = "posixlycorrect.com";
+                authelia_url = "https://auth.posixlycorrect.com";
+                default_redirection_url = "https://posixlycorrect.com";
+                same_site = "lax";
+                inactivity = "5 minutes";
+                expiration = "1 hour";
+                remember_me = "1 month";
+              }
+            ];
+          };
+
+          regulation = {
+            max_retries = 3;
+            find_time = "2 minutes";
+            ban_time = "5 minutes";
+          };
+
+          storage.local.path = "/var/lib/authelia-main/db.sqlite3";
+
+          # TODO: usar smtp
+          notifier.filesystem = {
+            filename = "/tmp/trash.txt";
+          };
+        };
+      };
+    };
+  };
+}
diff --git a/sys/srv/bepasty.nix b/sys/srv/bepasty.nix
index 964dbec..cfcc88b 100644
--- a/sys/srv/bepasty.nix
+++ b/sys/srv/bepasty.nix
@@ -9,10 +9,6 @@ with lib; {
       virtualHosts."send.posixlycorrect.com" = {
         enableACME = true;
         forceSSL = true;
-        extraConfig = ''
-          proxy_headers_hash_max_size 512;
-          proxy_headers_hash_bucket_size 128;
-        '';
         locations."/" = {
           proxyPass = "http://127.0.0.1:8989";
         };
diff --git a/sys/srv/default.nix b/sys/srv/default.nix
index 61ccd14..de92f8d 100644
--- a/sys/srv/default.nix
+++ b/sys/srv/default.nix
@@ -17,5 +17,6 @@ with lib; {
     ./jellyfin.nix
     ./msmtp.nix
     ./kuma.nix
+    ./authelia
   ];
 }
diff --git a/sys/srv/forgejo.nix b/sys/srv/forgejo.nix
index 4651285..2464514 100644
--- a/sys/srv/forgejo.nix
+++ b/sys/srv/forgejo.nix
@@ -16,10 +16,6 @@ with lib; {
         virtualHosts."git.posixlycorrect.com" = {
           enableACME = true;
           forceSSL = true;
-          extraConfig = ''
-            proxy_headers_hash_max_size 512;
-            proxy_headers_hash_bucket_size 128;
-          '';
           locations."/".proxyPass = "http://localhost:9170";
         };
       };
diff --git a/sys/srv/jellyfin.nix b/sys/srv/jellyfin.nix
index 07c8896..3a607b3 100644
--- a/sys/srv/jellyfin.nix
+++ b/sys/srv/jellyfin.nix
@@ -9,10 +9,6 @@ with lib; {
       virtualHosts."stream.posixlycorrect.com" = {
         enableACME = true;
         forceSSL = true;
-        extraConfig = ''
-          proxy_headers_hash_max_size 512;
-          proxy_headers_hash_bucket_size 128;
-        '';
         locations."/" = {
           proxyPass = "http://localhost:8096";
         };
diff --git a/sys/srv/jitsi.nix b/sys/srv/jitsi.nix
index 42c62e6..c4a011d 100644
--- a/sys/srv/jitsi.nix
+++ b/sys/srv/jitsi.nix
@@ -10,15 +10,12 @@ with lib; {
         enableACME = true;
         forceSSL = true;
         extraConfig = ''
-          proxy_headers_hash_max_size 512;
-          proxy_headers_hash_bucket_size 128;
-
-            ssl_verify_depth 1;
-            ssl_verify_client on;
-            ssl_client_certificate ${../../pki/gatekeeper_ca.pem};
-            if ($ssl_client_verify != "SUCCESS") {
-              return 403;
-            }
+          ssl_verify_depth 1;
+          ssl_verify_client on;
+          ssl_client_certificate ${../../pki/gatekeeper_ca.pem};
+          if ($ssl_client_verify != "SUCCESS") {
+            return 403;
+          }
         '';
       };
     };
diff --git a/sys/srv/kuma.nix b/sys/srv/kuma.nix
index e698c04..60594c8 100644
--- a/sys/srv/kuma.nix
+++ b/sys/srv/kuma.nix
@@ -9,10 +9,6 @@ with lib; {
       virtualHosts."status.posixlycorrect.com" = {
         enableACME = true;
         forceSSL = true;
-        extraConfig = ''
-          proxy_headers_hash_max_size 512;
-          proxy_headers_hash_bucket_size 128;
-        '';
         locations."/" = {
           proxyPass = "http://127.0.0.1:4456";
         };
diff --git a/sys/srv/mediawiki.nix b/sys/srv/mediawiki.nix
index d07bd80..d976d40 100644
--- a/sys/srv/mediawiki.nix
+++ b/sys/srv/mediawiki.nix
@@ -10,10 +10,7 @@ with lib; {
       virtualHosts."wiki.posixlycorrect.com" = {
         enableACME = true;
         forceSSL = true;
-        extraConfig = ''
-          proxy_headers_hash_max_size 512;
-          proxy_headers_hash_bucket_size 128;
-        '';
+        enableAuthelia = true;
       };
     };
     mediawiki = {
diff --git a/sys/srv/net.nix b/sys/srv/net.nix
index 9d22700..f49edaf 100644
--- a/sys/srv/net.nix
+++ b/sys/srv/net.nix
@@ -26,6 +26,10 @@ with lib; {
       recommendedOptimisation = true;
       recommendedProxySettings = true;
       recommendedTlsSettings = true;
+      commonHttpConfig = ''
+        proxy_headers_hash_max_size 512;
+        proxy_headers_hash_bucket_size 128;
+      '';
       logError = "/var/log/nginx/error.log";
       clientMaxBodySize = "99M";
       virtualHosts = {
diff --git a/sys/srv/vaultwarden.nix b/sys/srv/vaultwarden.nix
index 2b8dc91..0d81ee7 100644
--- a/sys/srv/vaultwarden.nix
+++ b/sys/srv/vaultwarden.nix
@@ -9,10 +9,6 @@ with lib; {
       virtualHosts."vault.posixlycorrect.com" = {
         enableACME = true;
         forceSSL = true;
-        extraConfig = ''
-          proxy_headers_hash_max_size 512;
-          proxy_headers_hash_bucket_size 128;
-        '';
         locations."/".proxyPass = "http://127.0.0.1:${toString config.services.vaultwarden.config.ROCKET_PORT}";
       };
     };