diff --git a/.gitignore b/.gitignore
index 66ecee4..ea12eb1 100644
--- a/.gitignore
+++ b/.gitignore
@@ -7,6 +7,8 @@
 
 !.envrc
 
+!.sops.yaml
+
 !/flake.nix
 !/flake.lock
 
@@ -17,5 +19,6 @@
 !modules/
 !docs/
 !images/
+!secrets/
 
 !/flake/
diff --git a/.sops.yaml b/.sops.yaml
new file mode 100644
index 0000000..27698bb
--- /dev/null
+++ b/.sops.yaml
@@ -0,0 +1,14 @@
+keys:
+  - &admin_yubikey1 age1yubikey1qvy5y8kxqc63y7fk0tfv43u499a8z8q332ff087lythry9cc6hdxxkznc6t
+  - &host_x1g13_old age1xfc7ksg69l5kwsxxgtynsuxgpwltcf9gmqlhfl7efq0clc8lwspqnveyx3
+creation_rules:
+  - path_regex: ^secrets/common/[^/]+\.ya?ml$
+    key_groups:
+      - age:
+          - *admin_yubikey1
+          - *host_x1g13_old
+  - path_regex: ^secrets/hosts/x1g13/[^/]+\.ya?ml$
+    key_groups:
+      - age:
+          - *admin_yubikey1
+          - *host_x1g13_old
diff --git a/docs/sops-key.md b/docs/sops-key.md
new file mode 100644
index 0000000..8dbc9d3
--- /dev/null
+++ b/docs/sops-key.md
@@ -0,0 +1,17 @@
+# Generate Sops key file
+
+```bash
+mkdir -p ~/.config/sops/age
+chmod 700 ~/.config/sops/age
+
+age-plugin-yubikey --identity --slot 1 \
+  > ~/.config/sops/age/yubikey-identity.txt
+
+chmod 600 ~/.config/sops/age/yubikey-identity.txt
+```
+
+## Edit sops file
+
+```bash
+sops secrets/common/system.yaml
+```
diff --git a/flake.lock b/flake.lock
index b693604..837b384 100644
--- a/flake.lock
+++ b/flake.lock
@@ -959,6 +959,7 @@
         "noctalia": "noctalia",
         "quickshell": "quickshell",
         "services-flake": "services-flake",
+        "sops-nix": "sops-nix",
         "stylix": "stylix",
         "systems": "systems_6",
         "treefmt-nix": "treefmt-nix_3",
@@ -1002,6 +1003,26 @@
         "type": "github"
       }
     },
+    "sops-nix": {
+      "inputs": {
+        "nixpkgs": [
+          "nixpkgs"
+        ]
+      },
+      "locked": {
+        "lastModified": 1780547341,
+        "narHash": "sha256-Gq8KNx5A7hBB3uGJaj6eQfLDIz5YdLu92gqBcvHvoUo=",
+        "owner": "Mic92",
+        "repo": "sops-nix",
+        "rev": "9ed65852b6257fbeae4355bc24ecfea307ca759a",
+        "type": "github"
+      },
+      "original": {
+        "owner": "Mic92",
+        "repo": "sops-nix",
+        "type": "github"
+      }
+    },
     "stylix": {
       "inputs": {
         "base16": "base16",
diff --git a/flake.nix b/flake.nix
index c766709..95922bb 100644
--- a/flake.nix
+++ b/flake.nix
@@ -51,6 +51,12 @@
       inputs.nixpkgs.follows = "nixpkgs";
     };
 
+    # Secrets management
+    sops-nix = {
+      url = "github:Mic92/sops-nix";
+      inputs.nixpkgs.follows = "nixpkgs";
+    };
+
     # Disk management
     disko = {
       url = "github:nix-community/disko";
diff --git a/modules/system/default.nix b/modules/system/default.nix
index a16f8ce..2206bcd 100644
--- a/modules/system/default.nix
+++ b/modules/system/default.nix
@@ -13,7 +13,9 @@
     ./nix.nix
     ./power.nix
     ./secure-boot.nix
+    ./sops.nix
     ./user
     ./version.nix
+    ./secret.nix
   ];
 }
diff --git a/modules/system/secret.nix b/modules/system/secret.nix
new file mode 100644
index 0000000..bb393d2
--- /dev/null
+++ b/modules/system/secret.nix
@@ -0,0 +1,14 @@
+_:
+let
+  commonSyetemSecrets = ../../secrets/common/system.yaml;
+in
+{
+  sops.secrets = {
+    "users/moons/hashedPassword" = {
+      sopsFile = commonSyetemSecrets;
+
+      # need before user creation
+      neededForUsers = true;
+    };
+  };
+}
diff --git a/modules/system/sops.nix b/modules/system/sops.nix
new file mode 100644
index 0000000..caf3184
--- /dev/null
+++ b/modules/system/sops.nix
@@ -0,0 +1,41 @@
+{
+  inputs,
+  pkgs,
+  ...
+}:
+{
+  imports = [
+    inputs.sops-nix.nixosModules.sops
+  ];
+
+  environment.systemPackages = with pkgs; [
+    # sops / age
+    sops
+    age
+    ssh-to-age
+
+    # YubiKey edit key
+    age-plugin-yubikey
+    yubikey-manager
+    pcsc-tools
+
+    # password hash generation
+    mkpasswd
+  ];
+
+  # age-plugin-yubikey depend
+  services.pcscd.enable = true;
+
+  services.openssh.enable = true;
+
+  sops = {
+    defaultSopsFormat = "yaml";
+
+    age = {
+      # system keys
+      sshKeyPaths = [
+        "/etc/ssh/ssh_host_ed25519_key"
+      ];
+    };
+  };
+}
diff --git a/modules/system/user/moons.nix b/modules/system/user/moons.nix
index c4c2f76..47d70c2 100644
--- a/modules/system/user/moons.nix
+++ b/modules/system/user/moons.nix
@@ -1,8 +1,15 @@
-{ pkgs, ... }:
 {
+  pkgs,
+  config,
+  ...
+}:
+{
+  users.mutableUsers = false;
+
   users.users.moons = {
     isNormalUser = true;
     description = "moons-14";
+    hashedPasswordFile = config.sops.secrets."users/moons/hashedPassword".path;
     extraGroups = [
       "adbusers"
       "docker"
diff --git a/secrets/common/system.yaml b/secrets/common/system.yaml
new file mode 100644
index 0000000..e9f7735
--- /dev/null
+++ b/secrets/common/system.yaml
@@ -0,0 +1,28 @@
+users:
+  moons:
+    hashedPassword: ENC[AES256_GCM,data:QtZei/BXPn/PDxUlOu0ZVrAfRM5jiHChAE5j5NVscPmm4OWjr94nPVOmJlYjL2WAiJY3/JSthmbrEIqiUF6E9qv10HQzAxzmZQ==,iv:ksshJX9S/20lw/8IDZYadNZLLE/gNgENZJ3/wRgJCds=,tag:xJPiO8O/q4rKmb+YNnpZdg==,type:str]
+sops:
+  age:
+    - enc: |
+        -----BEGIN AGE ENCRYPTED FILE-----
+        YWdlLWVuY3J5cHRpb24ub3JnL3YxCi0+IHBpdi1wMjU2IGxWc2NMZyBBM09Pclhu
+        K0ozcS90TG9Qam1YUjdCUGw5QjRoNXNGMU92WVdJOVluUk0vNQpjb3AxeGVpaFBT
+        L2hLYnZ1WWtOQjdyRFR1SnNMb1JITTVwWlNXb003YUFJCi0tLSBPNnowdm00ZEhR
+        b2VGZ1drRG4rU01TODk5Rm5KbXJjVkNhQ0hNeUxwdXBzCqKtUyprjagTVajskgXg
+        OBMMuflEZQH+mtFWsBc0k1Mm7MAS8DpMVLNZnkfNNPpFTP4pAOWFd2LhuMkDONFQ
+        vnA=
+        -----END AGE ENCRYPTED FILE-----
+      recipient: age1yubikey1qvy5y8kxqc63y7fk0tfv43u499a8z8q332ff087lythry9cc6hdxxkznc6t
+    - enc: |
+        -----BEGIN AGE ENCRYPTED FILE-----
+        YWdlLWVuY3J5cHRpb24ub3JnL3YxCi0+IFgyNTUxOSBPU0d5bVUrditWVCtDbyt6
+        WFpJTVdLOGpqZ1hLZTJGZi83MXZLMzR6RVhFCnBZRU53V3NvYXFpVXVJaDJHdlhz
+        SlV4NFUvTDZUQWdTaUJNZElidk1zMjgKLS0tIEd3QTRldzBJamp0OWhNUTBFMExC
+        dlhiMGp4b1JqY2JVTG5vSitadXI4cEUKvhqw+A5CXktuHR3JBDNKg2SrNIy4++l8
+        e58uQoTjJab1ivvLVAZOdtIdoulca50W9+ALNOFqBn9j5VD0BfFeKg==
+        -----END AGE ENCRYPTED FILE-----
+      recipient: age1xfc7ksg69l5kwsxxgtynsuxgpwltcf9gmqlhfl7efq0clc8lwspqnveyx3
+  lastmodified: "2026-06-15T10:20:19Z"
+  mac: ENC[AES256_GCM,data:Tw58FneoksiOuol1aUOFXoAnFiTzddmFfYAA0B0RfPPyj6UKQbBvRYJhOMuOMRE1fVlDhqxxDiqZI5y14vJg8gLusAZt1JKi7ODR7MqcImvxboaee8DIj4uIcN254g0c0cmZWsGrt7yTYoSLDUc3QdAxj9/Az/CMls6XjM+RL8E=,iv:XGgWgbexCUxzuJzRVG3V2GZGwmwjAtowgz+NRPxk1+o=,tag:FwYJXfwS2f70okl0bhS+Sw==,type:str]
+  unencrypted_suffix: _unencrypted
+  version: 3.13.1
diff --git a/shells/dotnix.nix b/shells/dotnix.nix
index 1afb4b2..bef8bb2 100644
--- a/shells/dotnix.nix
+++ b/shells/dotnix.nix
@@ -9,12 +9,27 @@ _: {
       devShells.dotnix = pkgs.mkShell {
         packages = [
           config.treefmt.build.wrapper
-          pkgs.gitleaks
+
           pkgs.git
+          pkgs.gitleaks
           pkgs.pre-commit
+
+          # sops-nix / age
+          pkgs.sops
+          pkgs.age
+          pkgs.ssh-to-age
+
+          # YubiKey for sops editing
+          pkgs.age-plugin-yubikey
+          pkgs.yubikey-manager
+          pkgs.pcsc-tools
         ];
 
-        shellHook = config.pre-commit.settings.shellHook;
+        shellHook = ''
+          ${config.pre-commit.settings.shellHook}
+
+          export SOPS_AGE_KEY_FILE="$HOME/.config/sops/age/yubikey-identity.txt"
+        '';
       };
     };
 }