diff --git a/flake.lock b/flake.lock
index ef812f1..138d6cb 100644
--- a/flake.lock
+++ b/flake.lock
@@ -132,6 +132,7 @@
       },
       "original": {
         "owner": "nix-community",
+        "ref": "master",
         "repo": "home-manager",
         "type": "github"
       }
@@ -147,6 +148,7 @@
       },
       "original": {
         "owner": "nix-community",
+        "ref": "master",
         "repo": "impermanence",
         "type": "github"
       }
@@ -171,6 +173,7 @@
       },
       "original": {
         "owner": "nix-community",
+        "ref": "master",
         "repo": "lanzaboote",
         "type": "github"
       }
@@ -349,6 +352,7 @@
       },
       "original": {
         "owner": "adtya",
+        "ref": "main",
         "repo": "varnam-nix",
         "type": "github"
       }
diff --git a/flake.nix b/flake.nix
index 76ba621..82bc8e9 100644
--- a/flake.nix
+++ b/flake.nix
@@ -13,15 +13,15 @@
   };
 
   inputs = {
-    nixpkgs.url = "github:NixOS/nixpkgs/nixos-unstable";
+    nixpkgs.url = "github:NixOS/nixpkgs?ref=nixos-unstable";
     home-manager = {
-      url = "github:nix-community/home-manager";
+      url = "github:nix-community/home-manager?ref=master";
       inputs.nixpkgs.follows = "nixpkgs";
     };
     flake-utils.url = "github:numtide/flake-utils";
-    impermanence.url = "github:nix-community/impermanence";
-    lanzaboote.url = "github:nix-community/lanzaboote";
-    varnam-nix.url = "github:adtya/varnam-nix";
+    impermanence.url = "github:nix-community/impermanence?ref=master";
+    lanzaboote.url = "github:nix-community/lanzaboote?ref=master";
+    varnam-nix.url = "github:adtya/varnam-nix?ref=main";
   };
 
   outputs =