diff --git a/.sops.yaml b/.sops.yaml
index a14898b..462abf5 100644
--- a/.sops.yaml
+++ b/.sops.yaml
@@ -63,6 +63,16 @@ creation_rules:
           - *lxc-nix-cache
           - *proxmox-nix-cache
 
+  # Host keytab for nix-cache FreeIPA enrollment (binary sops file).
+  # Generate with: sops -e --input-type binary /tmp/nix-cache.keytab > secrets/nix-cache.keytab
+  - path_regex: secrets/nix-cache\.keytab$
+    key_groups:
+      - age:
+          - *admin
+          - *linode-nix-cache
+          - *lxc-nix-cache
+          - *proxmox-nix-cache
+
   - path_regex: secrets/server\.yaml$
     key_groups:
       - age:
diff --git a/certs/ipa-ca.crt b/certs/ipa-ca.crt
new file mode 100644
index 0000000..614814a
--- /dev/null
+++ b/certs/ipa-ca.crt
@@ -0,0 +1,25 @@
+-----BEGIN CERTIFICATE-----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=
+-----END CERTIFICATE-----
diff --git a/hosts/nix-cache/host.nix b/hosts/nix-cache/host.nix
index 89f6c55..b9b2c0f 100644
--- a/hosts/nix-cache/host.nix
+++ b/hosts/nix-cache/host.nix
@@ -6,10 +6,15 @@
       name = "nix-cache";
       sopsFile = ../../secrets/nix-cache.yaml;
     })
+    (import ../../modules/ipa/client.nix {
+      keytabSopsFile = ../../secrets/nix-cache.keytab;
+      caCertFile = ../../certs/ipa-ca.crt;
+    })
   ];
 
   networking = {
     hostName = vars.nixCacheHost;
+    domain = vars.homeDomain;
     useDHCP = false;
     interfaces.${vars.lxcLanInterface}.ipv4.addresses = [{
       address = vars.nixCacheIp;
diff --git a/modules/ipa/client.nix b/modules/ipa/client.nix
new file mode 100644
index 0000000..db83042
--- /dev/null
+++ b/modules/ipa/client.nix
@@ -0,0 +1,75 @@
+# Fully declarative FreeIPA domain membership.
+#
+# Configures security.ipa (SSSD, Kerberos, PAM, NSSwitch) and places a
+# pre-provisioned host keytab via sops-nix so no imperative ipa-client-install
+# step is needed after deployment.
+#
+# Usage (in a host.nix imports list):
+#   (import ../../modules/ipa/client.nix {
+#     keytabSopsFile = ../../secrets/nix-cache.keytab;
+#     caCertFile     = ../../certs/ipa-ca.crt;
+#   })
+#
+# One-time operator setup per host (do this BEFORE deploying):
+#
+#   1. Fetch the IPA CA certificate (public — safe to commit):
+#        curl -o certs/ipa-ca.crt http://<ipa-server>/ipa/config/ca.crt
+#      Replace the placeholder at certs/ipa-ca.crt and commit it.
+#
+#   2. On the FreeIPA server, add the host and generate a keytab:
+#        ipa host-add <fqdn> --ip-address=<ip>
+#        ipa-getkeytab -s <ipa-server> -p host/<fqdn> -k /tmp/<host>.keytab
+#
+#   3. sops-encrypt the keytab as a binary secret from your admin machine
+#      (must run from repo root; sops matches creation rules against the file
+#      path, so copy to secrets/ first and encrypt in-place):
+#        cp /tmp/<host>.keytab secrets/<host>.keytab
+#        sops -e --input-type binary -i secrets/<host>.keytab
+#      Add secrets/<host>.keytab to .sops.yaml with the host's age key as a
+#      recipient (see the nix-cache.keytab entry for the pattern), then run:
+#        scripts/secrets/sync-host-keys.sh <target>   # if not done yet
+#        sops updatekeys secrets/<host>.keytab
+#      Commit the encrypted file.
+#
+#   4. nixos-rebuild switch (or create-proxmox-resource.sh) — no further
+#      manual enrollment steps required.
+#
+# vars dependencies: homeDomain, ipaServer
+
+{ keytabSopsFile, caCertFile }:
+{ config, lib, pkgs, vars, ... }:
+
+let
+  realm = lib.strings.toUpper vars.homeDomain;
+  fqdn = "${config.networking.hostName}.${vars.homeDomain}";
+  # "sweet.home" -> "dc=sweet,dc=home"
+  basedn = lib.strings.concatMapStringsSep "," (c: "dc=${c}") (lib.strings.splitString "." vars.homeDomain);
+  # security.ipa.certificate expects a derivation (package), not a raw path.
+  caCertPkg = pkgs.writeText "ipa-ca.crt" (builtins.readFile caCertFile);
+in
+{
+  security.ipa = {
+    enable = true;
+    domain = vars.homeDomain;
+    realm = realm;
+    server = vars.ipaServer;
+    certificate = caCertPkg;
+    basedn = basedn;
+    ipaHostname = fqdn;
+    offlinePasswords = true;
+    cacheCredentials = true;
+  };
+
+  # Host keytab: pre-provisioned on the IPA server, sops-encrypted binary.
+  # Placed at /etc/krb5.keytab before SSSD starts so the host authenticates
+  # to IPA without running ipa-client-install.
+  sops.secrets."ipa-host-keytab" = {
+    sopsFile = keytabSopsFile;
+    format = "binary";
+    path = "/etc/krb5.keytab";
+    owner = "root";
+    group = "root";
+    mode = "0600";
+    restartUnits = [ "sssd.service" ];
+  };
+}
diff --git a/secrets/nix-cache.keytab b/secrets/nix-cache.keytab
new file mode 100644
index 0000000..65aa101
--- /dev/null
+++ b/secrets/nix-cache.keytab
@@ -0,0 +1,26 @@
+{
+	"data": "ENC[AES256_GCM,data:z2bazlADvtWkGcY4an7NgZgIDSDq8KmYpSq8tcBleW/33HlElMNhdmje8m8hd7WxgrVvCQDdlAfodBLj2mjbgSwBptlPX2zbwcmJdm0g0Ope+YyQZucIio7NnBaYa+OK8meWqmxO2WEeOk+hnNfNPbt8MkzF/FMMbP8xv9wSTKP9CDdmO7s8rdg8G1JxVfn9dyaSDUTuA2JGNtbh+osd4CtNCV/bc84MjXDZTgTfT0W/uv8VH3iPNT7BhQbU9FIY4dsFRYBf758VtJ+3mTBiQkR38IevJBvhFB7Wiqn118LSBgjdTKJnBwmGo6lMdo0LRYHEgUnb2ejhWMNie19x+LEAErDki0RBmjc2BbnOF908kUlW2fUPo5fz/hlfqlhDLS1uOxESKhfnKt7s5qzWiMX/nohpknVfyMbmu9j/M571z9sgFnJAylpW3NLp53lX8N9mINwRGXsyL/ijbNE=,iv:M/MNquAGN+lIIyVVvFRgKR6DKAhLclc/OY1HV5Xwoog=,tag:eEuURMErSqsoh+l9ZaHY9Q==,type:str]",
+	"sops": {
+		"age": [
+			{
+				"enc": "-----BEGIN AGE ENCRYPTED FILE-----\nYWdlLWVuY3J5cHRpb24ub3JnL3YxCi0+IFgyNTUxOSBqZlUxRG0zR3IzMlpDL3Vl\nNmRWQXUvc1NDek5wbWtKVEFTcTlxL3ZoWldNCmJVMkFtbDkxN1FGQ2VLTlhBUW5Q\nZ3VzL0UydUQ2YnlUMmtqa1Z0d0FSVFUKLS0tIGJFelc4Rm84T3ZHSGZDdnNUbUFM\nRXZHV3N3aVlSOXhUZk04UFRMWU5TbFUKhPU80PVYuDFUCxu1CA8+W8bqkr+Ne2fh\n+nBUPJbGxfN9TyD9tUC77AMbcL1R2L5x+SSAh0bEgSWE24/RjsuVKw==\n-----END AGE ENCRYPTED FILE-----\n",
+				"recipient": "age1njap586hc0q43kr03g6c8eqhdsmk8zcafkl3f83xwlc2gqhlmfgs4tmwad"
+			},
+			{
+				"enc": "-----BEGIN AGE ENCRYPTED FILE-----\nYWdlLWVuY3J5cHRpb24ub3JnL3YxCi0+IFgyNTUxOSB3M1o3S2FibHV6N2tIOFEx\nRytJRDFIUU05azNDbWlpaDdFQXFRWlBUNnlFCnBwNVB0SEVwL3NWNS9aeG4xSUI1\nV3NOcUFxUUhaODYyWXdFMEhWeFpvancKLS0tIHY4NHFQRGJwUURQbWZ2cGlSdm9s\nOFJodGZkekk3UnBRRUwxb2YrQ1ZPcU0K0tCapb1hfVHFSNpmESXexYa5k9OE9Tha\n51QpU4mZHKGrnWPK/kyj7rHiz95TLsmwUdA8Q2hOiYNSxEaVBjYDQw==\n-----END AGE ENCRYPTED FILE-----\n",
+				"recipient": "age1jcx3yajjhghn8qh8za3yeu8nxykzlg3p4nrv03vnfvzl0mzayg2qmg940e"
+			},
+			{
+				"enc": "-----BEGIN AGE ENCRYPTED FILE-----\nYWdlLWVuY3J5cHRpb24ub3JnL3YxCi0+IFgyNTUxOSBkTmNrbUFoVFVGcytzQkk1\nMUxDdmJGL0xDcUNZaDFRQnUwNXoyMU90SEVvCi9EaTlVOGlMeUZtQzRJS1J2TTJY\neWdkMGNFMWZzQXVKOU5KcXVvalk1ekkKLS0tIDN2MlRQcG5aQnN3bUMrSDdvc09X\nM29hQ0pJRzk1amRHaS9mRlhrb2FMZG8KEWkSSP+MqGRU75qo7ctOCL7qHhyCM3l4\nL+ga1XOKxRsQkKQPozCi5Bm+k28W9hIDaC34Rw9difxICM9Z1rAbOA==\n-----END AGE ENCRYPTED FILE-----\n",
+				"recipient": "age1ufg390ydrmma849t9xfkxxl5xvdkk6mngnlzhmy7mvuaje8sgcmsmnq6l7"
+			},
+			{
+				"enc": "-----BEGIN AGE ENCRYPTED FILE-----\nYWdlLWVuY3J5cHRpb24ub3JnL3YxCi0+IFgyNTUxOSA1TUtxVjJ2STFpU3RNdWpJ\nVjcwUHVORVN6L1pKVC9TeWt4cTNoR2pPWVRBCkR4QVJ1bHFUa2Z5aWw1bG0vQWVy\ncjNGRDl5REZzbzdZWTFMRkU1eHFTc1kKLS0tIHNLVDFiRkRKTHhrSEx2S0J1R3cx\nSkdEQWJya1ptTTRqUjJZT3FFaFhkd0kKgecHrnzW9+Eb+b7c0z1yR+Y0Czsr9Kjh\nx1UUOfleHntJUCs8oYcOogKknEnhBJJoJ5oe/gWruRSwle1fs3cBqQ==\n-----END AGE ENCRYPTED FILE-----\n",
+				"recipient": "age1jlltcv5jcnm40z5k0q6hv053k2rqpqvemtuecdwn527uw8uqz4es3x7m68"
+			}
+		],
+		"lastmodified": "2026-07-27T21:22:58Z",
+		"mac": "ENC[AES256_GCM,data:VG2ygV4X6yMxGlJgq3sN4GAzgVqiD06noyMxB2yb/FCmiFVYZAH/9LqF//G7MTInfIjFrTDyoHAny+m/ztUrJkHXI1Fzg0U8R/zYyQ6wj/GguL0gyhA70uriQhvHsRHefHPa7Km61Blo9cME6CBJWejtRvh1IMw9itAioVrSIZE=,iv:zjxNG6IYxkcNqLk08NADoDiIbS6at86y136SBzadW1U=,tag:sj4ZRR7ixU8h7aOUJmTCYg==,type:str]",
+		"version": "3.13.2"
+	}
+}
diff --git a/variables.nix b/variables.nix
index ec50ec2..e438178 100644
--- a/variables.nix
+++ b/variables.nix
@@ -17,6 +17,7 @@
   dockerIp = "192.168.2.225"; # docker Proxmox VM LAN IP
   pbsIp = "192.168.2.244"; # Proxmox Backup Server LAN IP (not NixOS-managed)
   domainControllerIp = "192.168.2.253"; # FreeIPA domain controller / primary DNS (not NixOS-managed)
+  ipaServer = "domain-controller.sweet.home"; # FreeIPA server hostname (used by security.ipa and Kerberos; must be a resolvable FQDN, not an IP)
 
   # Cross-host references (LAN hostnames/users other hosts reach over the network)
   nixCacheHost = "nix-cache"; # substituter/remote-builder hostname