diff --git a/helm-overrides/gke-toolshed-prd-usc1/vault/custom-values.yaml b/helm-overrides/gke-toolshed-prd-usc1/vault/custom-values.yaml
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+vault:
+  # GKE counterpart of helm-overrides/k8s-admin-prd-ase1/vault, same chart
+  # (0.34.1) and same shape — production mode, file storage, standalone, no
+  # HA — with one substantial difference: this Vault unseals itself from
+  # Cloud KMS instead of by hand.
+  #
+  # The homelab unseals with 3 of 5 Shamir keys after every restart. That
+  # was fine on an always-on VM. Here the nodes are spot and can be
+  # reclaimed at any hour, and a sealed Vault means every secret in the
+  # cluster is unavailable until a human notices. The trade, stated plainly:
+  # unsealing now depends on GCP IAM rather than on people holding key
+  # shares.
+  #
+  # This is a fresh install, not an adoption. Init is still a one-off manual
+  # step (`vault operator init`), and with a KMS seal it returns RECOVERY
+  # keys plus a root token — recovery keys cannot unseal a running Vault,
+  # they exist to recover or rekey it. Keep them and the root token in a
+  # password manager; they belong in neither Git nor Vault itself.
+
+  injector:
+    enabled: false
+
+  server:
+    # The Workload Identity binding Terraform created names exactly
+    # vault/vault — this namespace and this service account name. The
+    # annotation is the other half of that pair. Miss either and Vault
+    # starts, fails to reach KMS, and stays sealed with a permission error
+    # that does not mention Workload Identity at all.
+    serviceAccount:
+      create: true
+      name: vault
+      annotations:
+        iam.gke.io/gcp-service-account: toolshed-vault@toolshed-testing-508208.iam.gserviceaccount.com
+
+    dataStorage:
+      enabled: true
+      # 10Gi rather than the homelab's 5Gi: that number exists only because
+      # local-path cannot expand a bound volume. standard-rwo can expand, so
+      # this is the chart default, not a constraint.
+      size: 10Gi
+      storageClass: standard-rwo
+
+    ha:
+      enabled: false
+
+    resources:
+      requests:
+        cpu: 100m
+        memory: 128Mi
+      limits:
+        memory: 256Mi
+
+    standalone:
+      enabled: true
+      # `ui = true` here AND ui.enabled below are both required — the chart
+      # has two separate toggles for the same thing, and setting only one
+      # leaves the UI 404ing (claude.md issue #10).
+      #
+      # The seal stanza's values come from terraform output vault_seal, so
+      # Terraform and this file cannot disagree about which key Vault
+      # unseals with. No credentials appear here: the pod authenticates to
+      # KMS as its Workload Identity, so there is no key file to mount,
+      # rotate, or leak.
+      config: |
+        ui = true
+        listener "tcp" {
+          address = "[::]:8200"
+          cluster_address = "[::]:8201"
+          tls_disable = "true"   # lab only - enable TLS for anything beyond local testing
+        }
+        storage "file" {
+          path = "/vault/data"
+        }
+        seal "gcpckms" {
+          project    = "toolshed-testing-508208"
+          region     = "us-central1"
+          key_ring   = "toolshed-vault"
+          crypto_key = "unseal"
+        }
+
+    # Single host — no Tailscale here. Plain HTTP through Contour, matching
+    # tls_disable above.
+    ingress:
+      enabled: true
+      ingressClassName: contour
+      hosts:
+        - host: "vault.35.238.248.203.nip.io"
+          paths: []
+
+  ui:
+    enabled: true