diff --git a/hosts/comfy-station/configuration.nix b/hosts/comfy-station/configuration.nix
index cf5e409..40c10ca 100644
--- a/hosts/comfy-station/configuration.nix
+++ b/hosts/comfy-station/configuration.nix
@@ -111,7 +111,7 @@
   nix = {
     settings = {
       substituters = [
-        "https://aseipp-nix-cache.global.ssl.fastly.net"
+        "https://aseipp-nix-cache.freetls.fastly.net"
         "https://nix-community.cachix.org"
         "https://cache.nixos.org/"
       ];
diff --git a/hosts/harbor/configuration.nix b/hosts/harbor/configuration.nix
index 2b16219..97eebf2 100644
--- a/hosts/harbor/configuration.nix
+++ b/hosts/harbor/configuration.nix
@@ -29,9 +29,14 @@
     key = "adminPassword";
   };
 
-  # Configure nix and garbage collection
+  # gc settings and binary caches
   nix = {
     settings = {
+      substituters = [
+        "https://aseipp-nix-cache.freetls.fastly.net"
+        "https://nix-community.cachix.org"
+        "https://cache.nixos.org/"
+      ];
       experimental-features = ["nix-command" "flakes"];
       auto-optimise-store = true;
     };
diff --git a/hosts/monolith/configuration.nix b/hosts/monolith/configuration.nix
index 1fbeddb..7409cbc 100644
--- a/hosts/monolith/configuration.nix
+++ b/hosts/monolith/configuration.nix
@@ -202,9 +202,14 @@
   # (e.g. man configuration.nix or on https://nixos.org/nixos/options.html).
   system.stateVersion = "24.11"; # Did you read the comment?
 
-  # gc settings
+  # gc settings and binary caches
   nix = {
     settings = {
+      substituters = [
+        "https://aseipp-nix-cache.freetls.fastly.net"
+        "https://nix-community.cachix.org"
+        "https://cache.nixos.org/"
+      ];
       experimental-features = ["nix-command" "flakes"];
       auto-optimise-store = true;
     };