diff --git a/image-recipe/configs/nginx-archipelago.conf b/image-recipe/configs/nginx-archipelago.conf
index 72e55eeb..c84cd389 100644
--- a/image-recipe/configs/nginx-archipelago.conf
+++ b/image-recipe/configs/nginx-archipelago.conf
@@ -18,6 +18,17 @@ server {
     root /opt/archipelago/web-ui;
     index index.html;
 
+    # This node's CA, for devices that have not trusted it yet. Deliberately
+    # unauthenticated and served over plain HTTP: a device fetches this BEFORE
+    # it can validate the node's own certificate, so requiring HTTPS or a login
+    # here would be a chicken-and-egg. It is a public certificate — never a key
+    # — and the dashboard shows its fingerprint so it can be checked on sight.
+    location = /ca.crt {
+        alias /etc/archipelago/ssl/ca-download.crt;
+        default_type application/x-x509-ca-cert;
+        add_header Content-Disposition 'attachment; filename="archipelago-node-ca.crt"';
+    }
+
     # Security headers
     add_header X-Content-Type-Options "nosniff" always;
     add_header X-Frame-Options "SAMEORIGIN" always;
@@ -934,6 +945,13 @@ server {
     index index.html;
     include snippets/archipelago-pwa.conf;
 
+    # Same CA download over HTTPS — see the note in the HTTP block above.
+    location = /ca.crt {
+        alias /etc/archipelago/ssl/ca-download.crt;
+        default_type application/x-x509-ca-cert;
+        add_header Content-Disposition 'attachment; filename="archipelago-node-ca.crt"';
+    }
+
     # Security headers
     add_header X-Content-Type-Options "nosniff" always;
     add_header X-Frame-Options "SAMEORIGIN" always;
diff --git a/neode-ui/src/views/settings/NodeCertificateSection.vue b/neode-ui/src/views/settings/NodeCertificateSection.vue
new file mode 100644
index 00000000..71554dd0
--- /dev/null
+++ b/neode-ui/src/views/settings/NodeCertificateSection.vue
@@ -0,0 +1,130 @@
+<script setup lang="ts">
+import { onMounted, ref } from 'vue'
+
+// This node signs its own certificates with a CA that never leaves it. Install
+// that CA once per device and every port on this node is trusted — which is what
+// lets a gated app load inside the dashboard's frame at all: a cert warning
+// cannot be clicked through inside an iframe, so an untrusted app port simply
+// fails to render.
+
+const fingerprint = ref('')
+const fingerprintError = ref('')
+const loading = ref(true)
+const caAvailable = ref(false)
+
+// SHA-256 over the DER bytes — the same number `openssl x509 -fingerprint
+// -sha256` prints, so the two can be compared character for character.
+async function computeFingerprint(pem: string): Promise<string> {
+  const body = pem
+    .replace(/-----BEGIN CERTIFICATE-----/, '')
+    .replace(/-----END CERTIFICATE-----/, '')
+    .replace(/\s+/g, '')
+  const der = Uint8Array.from(atob(body), (c) => c.charCodeAt(0))
+  const digest = await crypto.subtle.digest('SHA-256', der)
+  return Array.from(new Uint8Array(digest))
+    .map((b) => b.toString(16).padStart(2, '0').toUpperCase())
+    .join(':')
+}
+
+onMounted(async () => {
+  try {
+    const res = await fetch('/ca.crt', { cache: 'no-store' })
+    if (!res.ok) throw new Error(`HTTP ${res.status}`)
+    const pem = await res.text()
+    if (!pem.includes('BEGIN CERTIFICATE')) throw new Error('not a certificate')
+    caAvailable.value = true
+
+    // crypto.subtle only exists in a secure context. That is exactly the case
+    // this feature is meant to fix, so an HTTP dashboard lands here — say so
+    // and give the offline command rather than showing nothing.
+    if (!window.crypto?.subtle) {
+      fingerprintError.value =
+        'The fingerprint cannot be computed over a plain HTTP connection. Verify it on the node instead: openssl x509 -in /etc/archipelago/ssl/ca.crt -noout -fingerprint -sha256'
+    } else {
+      fingerprint.value = await computeFingerprint(pem)
+    }
+  } catch {
+    caAvailable.value = false
+  } finally {
+    loading.value = false
+  }
+})
+</script>
+
+<template>
+  <div class="mb-6">
+    <h3 class="text-base font-medium text-white/90 mb-1">Node certificate</h3>
+    <p class="text-sm text-white/60 mb-4">
+      Install this node's certificate on a device and it stops warning you about
+      this node — on every port, not just the dashboard. Apps that open inside
+      the dashboard need this: a certificate warning cannot be accepted inside an
+      embedded frame, so an untrusted app shows nothing at all.
+    </p>
+
+    <div v-if="loading" class="text-sm text-white/50">Checking…</div>
+
+    <div
+      v-else-if="!caAvailable"
+      class="p-3 bg-white/5 border border-white/10 rounded-lg text-sm text-white/70"
+    >
+      This node has not generated a certificate authority yet. Run
+      <code class="px-1 py-0.5 bg-black/30 rounded text-xs">scripts/setup-node-ca.sh</code>
+      on the node, then reload this page.
+    </div>
+
+    <div v-else class="space-y-4">
+      <div>
+        <a
+          href="/ca.crt"
+          download="archipelago-node-ca.crt"
+          class="inline-flex items-center gap-2 px-4 py-3 glass-button rounded-lg text-sm font-semibold"
+        >
+          <svg class="w-4 h-4" fill="none" stroke="currentColor" viewBox="0 0 24 24">
+            <path stroke-linecap="round" stroke-linejoin="round" stroke-width="2" d="M4 16v1a3 3 0 003 3h10a3 3 0 003-3v-1m-4-4l-4 4m0 0l-4-4m4 4V4" />
+          </svg>
+          Download this node's certificate
+        </a>
+      </div>
+
+      <div>
+        <p class="text-sm font-medium text-white/80 mb-1">Fingerprint (SHA-256)</p>
+        <p v-if="fingerprint" class="font-mono text-xs text-white/70 break-all select-all">{{ fingerprint }}</p>
+        <p v-else class="text-xs text-orange-300/80">{{ fingerprintError }}</p>
+        <p class="text-xs text-white/50 mt-2">
+          Check this matches the fingerprint the node itself prints before you trust
+          it. If they differ, something is intercepting the connection — do not install it.
+        </p>
+      </div>
+
+      <details class="group">
+        <summary class="cursor-pointer text-sm font-medium text-white/80 py-2">
+          How to install it
+        </summary>
+        <div class="mt-2 space-y-3 text-sm text-white/60">
+          <p><strong class="text-white/80">macOS</strong> — open the file, add it to the
+            <em>login</em> keychain, then find it in Keychain Access, open it, expand Trust
+            and set “When using this certificate” to <em>Always Trust</em>.</p>
+          <p><strong class="text-white/80">iOS / iPadOS</strong> — download it in Safari and
+            allow the profile, then Settings → General → VPN &amp; Device Management to
+            install it, and finally Settings → General → About → Certificate Trust Settings
+            to switch it on. Both steps are required.</p>
+          <p><strong class="text-white/80">Windows</strong> — right-click → Install
+            Certificate → Local Machine → place it in <em>Trusted Root Certification
+            Authorities</em>.</p>
+          <p><strong class="text-white/80">Android</strong> — Settings → Security →
+            Encryption &amp; credentials → Install a certificate → CA certificate.</p>
+          <p><strong class="text-white/80">Linux</strong> — copy to
+            <code class="px-1 py-0.5 bg-black/30 rounded text-xs">/usr/local/share/ca-certificates/</code>
+            and run <code class="px-1 py-0.5 bg-black/30 rounded text-xs">sudo update-ca-certificates</code>.
+            Firefox keeps its own store — add it under Settings → Privacy &amp; Security →
+            View Certificates → Authorities.</p>
+          <p class="text-white/50">
+            You are trusting this node, not a company. The signing key stays on the node
+            and only ever signs this node's own address. Anyone who takes the node also
+            takes that key — remove the certificate from your devices if you retire it.
+          </p>
+        </div>
+      </details>
+    </div>
+  </div>
+</template>
diff --git a/neode-ui/src/views/settings/SystemSection.vue b/neode-ui/src/views/settings/SystemSection.vue
index abc794ae..a4b8ab3f 100644
--- a/neode-ui/src/views/settings/SystemSection.vue
+++ b/neode-ui/src/views/settings/SystemSection.vue
@@ -5,6 +5,7 @@ import ClaudeAuthSection from '@/views/settings/ClaudeAuthSection.vue'
 import AIDataAccessSection from '@/views/settings/AIDataAccessSection.vue'
 import WebhookSection from '@/views/settings/WebhookSection.vue'
 import TelemetrySection from '@/views/settings/TelemetrySection.vue'
+import NodeCertificateSection from '@/views/settings/NodeCertificateSection.vue'
 import BackupSection from '@/views/settings/BackupSection.vue'
 import SystemDangerZone from '@/views/settings/SystemDangerZone.vue'
 </script>
@@ -16,6 +17,7 @@ import SystemDangerZone from '@/views/settings/SystemDangerZone.vue'
   <AIDataAccessSection />
   <WebhookSection />
   <TelemetrySection />
+  <NodeCertificateSection />
   <BackupSection />
   <SystemDangerZone />
 </template>
diff --git a/scripts/setup-node-ca.sh b/scripts/setup-node-ca.sh
new file mode 100755
index 00000000..727d4f19
--- /dev/null
+++ b/scripts/setup-node-ca.sh
@@ -0,0 +1,149 @@
+#!/usr/bin/env bash
+# Per-node certificate authority.
+#
+# WHY THIS EXISTS
+#
+# The node used to serve a bare self-signed leaf (setup-https-dev.sh). A browser
+# can be told to trust that, but the exception is granted per ORIGIN — scheme +
+# host + PORT. The dashboard on :443 and an app on :8334 are different origins,
+# so each app port needed its own click-through, and a cert interstitial CANNOT
+# be accepted inside an iframe: the embedded app just fails.
+#
+# A CA fixes that structurally. The user installs ONE certificate; every leaf it
+# signs is then trusted, on every port, with no further prompts. Ports are not
+# part of a certificate's identity — one leaf with the right SANs covers every
+# port on the host — so this is what makes gated apps embeddable over HTTPS.
+#
+# The CA private key never leaves the node and signs nothing but this node's own
+# leaf. Installing it means trusting THIS node, not a third party.
+#
+# Idempotent: re-running reuses an existing CA and only reissues the leaf (which
+# is what you want when the node gains an address). Pass --force-ca to start over
+# — that invalidates every copy users have already installed.
+
+set -euo pipefail
+
+SSL_DIR="${ARCHY_SSL_DIR:-/etc/archipelago/ssl}"
+CA_CRT="$SSL_DIR/ca.crt"
+CA_KEY="$SSL_DIR/ca.key"
+CA_SRL="$SSL_DIR/ca.srl"
+LEAF_CRT="$SSL_DIR/archipelago.crt"
+LEAF_KEY="$SSL_DIR/archipelago.key"
+
+CA_DAYS="${ARCHY_CA_DAYS:-3650}"
+# Public CAs cap leaves at 398 days and browsers enforce it. That limit applies
+# to publicly-trusted roots, not a privately-installed one, but a shorter leaf
+# still bounds the damage from a key leak — and reissuing costs nothing here
+# because this script is re-run on address changes anyway.
+LEAF_DAYS="${ARCHY_LEAF_DAYS:-397}"
+
+FORCE_CA=false
+[ "${1:-}" = "--force-ca" ] && FORCE_CA=true
+
+NODE_NAME="$(hostname -s 2>/dev/null || echo archipelago)"
+
+log() { echo "  $*"; }
+
+mkdir -p "$SSL_DIR"
+chmod 755 "$SSL_DIR"
+
+# --- Subject alternative names -----------------------------------------------
+# Every name/address the node can be reached by must be in the leaf, because a
+# certificate is scoped to names, not ports. Missing one here means that access
+# path still throws a warning even after the CA is installed.
+collect_sans() {
+  local -a dns=() ips=()
+
+  dns+=("archipelago.local" "$NODE_NAME" "$NODE_NAME.local" "localhost")
+
+  # Tailscale gives a stable MagicDNS name; include it so tailnet access is clean.
+  if command -v tailscale >/dev/null 2>&1; then
+    local ts_name
+    ts_name="$(tailscale status --json 2>/dev/null \
+      | python3 -c 'import json,sys; d=json.load(sys.stdin); print((d.get("Self") or {}).get("DNSName","").rstrip("."))' 2>/dev/null || true)"
+    [ -n "$ts_name" ] && dns+=("$ts_name")
+  fi
+
+  # Every non-loopback address the host currently holds, plus loopback itself.
+  ips+=("127.0.0.1" "::1")
+  while read -r addr; do
+    [ -n "$addr" ] && ips+=("$addr")
+  done < <(ip -o addr show scope global 2>/dev/null | awk '{print $4}' | cut -d/ -f1 | sort -u)
+
+  local out="" i=1 j=1
+  for d in $(printf '%s\n' "${dns[@]}" | awk 'NF' | sort -u); do
+    out="${out}DNS.$i:$d,"; i=$((i+1))
+  done
+  for a in $(printf '%s\n' "${ips[@]}" | awk 'NF' | sort -u); do
+    out="${out}IP.$j:$a,"; j=$((j+1))
+  done
+  echo "${out%,}"
+}
+
+SAN="$(collect_sans)"
+[ -z "$SAN" ] && { echo "ERROR: no SANs resolved — refusing to issue a useless cert" >&2; exit 1; }
+
+# --- CA ----------------------------------------------------------------------
+if [ "$FORCE_CA" = true ] && [ -f "$CA_CRT" ]; then
+  log "--force-ca: replacing the existing CA (previously installed copies stop working)"
+  rm -f "$CA_CRT" "$CA_KEY" "$CA_SRL"
+fi
+
+if [ -f "$CA_CRT" ] && [ -f "$CA_KEY" ]; then
+  log "Reusing the existing node CA (installed copies keep working)"
+else
+  log "Creating this node's certificate authority…"
+  openssl req -x509 -nodes -newkey rsa:4096 -sha256 -days "$CA_DAYS" \
+    -keyout "$CA_KEY" -out "$CA_CRT" \
+    -subj "/CN=Archipelago Node CA ($NODE_NAME)/O=Archipelago/OU=Node CA" \
+    -addext "basicConstraints=critical,CA:TRUE,pathlen:0" \
+    -addext "keyUsage=critical,keyCertSign,cRLSign" 2>/dev/null
+  chmod 600 "$CA_KEY"
+  chmod 644 "$CA_CRT"
+fi
+
+# --- Leaf --------------------------------------------------------------------
+log "Issuing the server certificate for: $SAN"
+TMP="$(mktemp -d)"
+trap 'rm -rf "$TMP"' EXIT
+
+openssl req -nodes -newkey rsa:2048 -sha256 \
+  -keyout "$TMP/leaf.key" -out "$TMP/leaf.csr" \
+  -subj "/CN=$NODE_NAME/O=Archipelago" 2>/dev/null
+
+cat >"$TMP/leaf.ext" <<EOF
+basicConstraints=CA:FALSE
+keyUsage=critical,digitalSignature,keyEncipherment
+extendedKeyUsage=serverAuth
+subjectAltName=$SAN
+EOF
+
+openssl x509 -req -in "$TMP/leaf.csr" -CA "$CA_CRT" -CAkey "$CA_KEY" \
+  -CAcreateserial -CAserial "$CA_SRL" \
+  -out "$TMP/leaf.crt" -days "$LEAF_DAYS" -sha256 -extfile "$TMP/leaf.ext" 2>/dev/null
+
+# Swap in place only once both halves exist, so a failure mid-run cannot leave
+# nginx pointing at a cert whose key is gone.
+install -m 644 "$TMP/leaf.crt" "$LEAF_CRT"
+install -m 600 "$TMP/leaf.key" "$LEAF_KEY"
+
+# The dashboard serves this for download; it is a public certificate, never the key.
+install -m 644 "$CA_CRT" "$SSL_DIR/ca-download.crt"
+
+FP="$(openssl x509 -in "$CA_CRT" -noout -fingerprint -sha256 | cut -d= -f2)"
+log "CA fingerprint (SHA-256): $FP"
+
+if command -v systemctl >/dev/null 2>&1 && systemctl is-active --quiet nginx; then
+  if nginx -t >/dev/null 2>&1; then
+    systemctl reload nginx && log "nginx reloaded"
+  else
+    echo "WARNING: nginx config test failed — NOT reloading. Certs are in place; fix nginx and reload." >&2
+  fi
+fi
+
+cat <<EOF
+
+Done. Install $CA_CRT on each device that should reach this node without warnings.
+The dashboard serves it at /ca.crt (Settings → Node certificate).
+Verify the fingerprint above matches what the dashboard shows before trusting it.
+EOF