diff --git a/frontend/packages/dashboard/src/builds.js b/frontend/packages/dashboard/src/builds.js
index 37f4a1be..bb881809 100644
--- a/frontend/packages/dashboard/src/builds.js
+++ b/frontend/packages/dashboard/src/builds.js
@@ -131,6 +131,7 @@ const QUEUE_KIND_GLYPH = {
   graceful_stop: '⏹',
   start: '▶',
   stop: '■',
+  reconcile: '⇄',
 };
 const QUEUE_STATE_GLYPH = {
   queued: '⏸',
@@ -139,11 +140,33 @@ const QUEUE_STATE_GLYPH = {
   failed: '✖',
   cancelled: '⊘',
 };
+// Short display labels for the per-DAG node kinds (the primitive ops).
+const NODE_KIND_LABEL = {
+  prebuild: 'prebuild',
+  stop_for_update: 'stop',
+  swap: 'swap',
+  create: 'create',
+  meta_lock: 'meta lock',
+  reconcile: 'reconcile',
+  signal: 'signal',
+  drain: 'drain',
+  write_dropin: 'dropin',
+  write_perm_file: 'perm file',
+  approval_deploy: 'deploy',
+};
+
+// The currently-running node of a DAG (per-node `step` labels + build
+// logs live on nodes now; the DAG's `state` is a roll-up).
+function runningNode(entry) {
+  return (entry.nodes || []).find((n) => n.state === 'running') || null;
+}
+function firstFailedNode(entry) {
+  return (entry.nodes || []).find((n) => n.state === 'failed') || null;
+}
 
 function rebuildQueueEntryFingerprint(entry, isChild) {
   return JSON.stringify({
     state: entry.state,
-    step: entry.step,
     kind: entry.kind,
     agent: entry.agent,
     source: entry.source,
@@ -151,8 +174,7 @@ function rebuildQueueEntryFingerprint(entry, isChild) {
     enqueued_at: entry.enqueued_at,
     finished_at: entry.finished_at,
     reason: entry.reason,
-    error: entry.error,
-    build_log_id: entry.build_log_id,
+    nodes: (entry.nodes || []).map((n) => [n.kind, n.state, n.step, n.build_log_id, n.error]),
     isChild,
   });
 }
@@ -257,22 +279,39 @@ function renderQueueEntry(entry, _byId, isChild) {
     const r = entry.reason.split('\n')[0];
     li.append(' ', el('span', { class: 'rqe-reason', title: entry.reason }, '— ' + truncate(r, 60)));
   }
-  if (entry.step) {
-    li.append(el('div', { class: 'rqe-step' }, '↳ ' + entry.step));
+  // Per-node chain: every DAG node in dependency order with its own
+  // state glyph, live step label, and build-log link. This is the
+  // node-aware render that makes queue jumps / partial progress
+  // visible (e.g. reconcile running while swap failed).
+  const nodes = entry.nodes || [];
+  if (nodes.length) {
+    const chain = el('div', { class: 'rqe-nodes' });
+    nodes.forEach((n, i) => {
+      if (i > 0) chain.append(el('span', { class: 'rqe-node-arrow' }, ' → '));
+      const chip = el('span', {
+        class: 'rqe-node rqe-node-' + n.state,
+        title: n.kind + ' · ' + n.state + (n.error ? ' — ' + n.error : ''),
+      },
+        (QUEUE_STATE_GLYPH[n.state] || '?') + ' ' + (NODE_KIND_LABEL[n.kind] || n.kind));
+      chain.append(chip);
+      if (n.build_log_id != null) {
+        chain.append(el('a', {
+          class: 'rqe-log-link rqe-node-log',
+          href: '/builds.html?id=' + n.build_log_id + '#buildlogs',
+          target: '_blank',
+          title: 'view build log #' + n.build_log_id,
+        }, '⎙'));
+      }
+    });
+    li.append(chain);
   }
-  if (entry.build_log_id != null) {
-    li.append(
-      ' ',
-      el('a', {
-        class: 'rqe-log-link',
-        href: '/builds.html?id=' + entry.build_log_id + '#buildlogs',
-        target: '_blank',
-        title: 'view build log #' + entry.build_log_id,
-      }, 'logs →'),
-    );
+  const running = runningNode(entry);
+  if (running && running.step) {
+    li.append(el('div', { class: 'rqe-step' }, '↳ ' + running.step));
   }
-  if (entry.error) {
-    li.append(el('pre', { class: 'rqe-error', title: entry.error }, truncate(entry.error, 200)));
+  const failed = firstFailedNode(entry);
+  if (failed && failed.error) {
+    li.append(el('pre', { class: 'rqe-error', title: failed.error }, truncate(failed.error, 200)));
   }
   if (entry.state === 'queued') {
     const cancelForm = el('form', {
@@ -296,11 +335,12 @@ function renderQueueEntry(entry, _byId, isChild) {
 }
 
 // ─── running-rebuild live log ─────────────────────────────────────────────────
-// One persistent live-log panel for the currently-running rebuild (the queue
-// runs one build at a time). Keyed to the running entry's build_log_id and
-// kept in its own container (#rebuild-live-log) so the queue's row re-render
-// — which rebuilds rows as the build step advances — never tears down the open
-// SSE stream.
+// One persistent live-log panel for the first currently-building node
+// (build logs are per-node now; with buildSlots = 1 at most one nix
+// build runs at a time). Keyed to that node's build_log_id and kept in
+// its own container (#rebuild-live-log) so the queue's row re-render —
+// which rebuilds rows as the build step advances — never tears down the
+// open SSE stream.
 let liveLogEs = null;
 let liveLogId = null;
 let liveLogDone = false;
@@ -310,23 +350,36 @@ function closeLiveLogStream() {
   if (liveLogEs) { liveLogEs.close(); liveLogEs = null; }
 }
 
+// First (dag, node) pair with a running node that opened a build log.
+function findLiveBuild(queue) {
+  for (const e of queue || []) {
+    if (e.state !== 'running') continue;
+    for (const n of e.nodes || []) {
+      if (n.state === 'running' && n.build_log_id != null) {
+        return { entry: e, node: n };
+      }
+    }
+  }
+  return null;
+}
+
 function renderRebuildLiveLog(queue) {
   const root = $('rebuild-live-log');
   if (!root) return;
-  const running = (queue || []).find(
-    (e) => e.state === 'running' && e.build_log_id != null);
+  const live = findLiveBuild(queue);
 
-  if (!running) {
+  if (!live) {
     closeLiveLogStream();
     liveLogId = null;
     liveLogDone = false;
     if (!root.hidden) { root.hidden = true; root.replaceChildren(); }
     return;
   }
-  if (running.build_log_id === liveLogId && (liveLogEs || liveLogDone)) return;
+  const { entry: running, node: liveNode } = live;
+  if (liveNode.build_log_id === liveLogId && (liveLogEs || liveLogDone)) return;
 
   closeLiveLogStream();
-  liveLogId = running.build_log_id;
+  liveLogId = liveNode.build_log_id;
   liveLogDone = false;
   root.hidden = false;
   root.replaceChildren();
@@ -351,17 +404,18 @@ function renderRebuildLiveLog(queue) {
     toggle, ' ',
     el('span', { class: 'rebuild-live-log-title' }, 'live build log — '),
     el('code', { class: 'rqe-agent' }, running.agent),
-    ' ', el('span', { class: 'rqe-kind' }, running.kind || 'rebuild'),
+    ' ', el('span', { class: 'rqe-kind' },
+      (running.kind || 'rebuild') + ' · ' + (NODE_KIND_LABEL[liveNode.kind] || liveNode.kind)),
     ' ', badge, ' ',
     el('a', {
       class: 'rebuild-live-log-raw',
-      href: '/api/build-logs/id/' + running.build_log_id + '/raw',
-      download: 'build-log-' + running.build_log_id + '.txt',
+      href: '/api/build-logs/id/' + liveNode.build_log_id + '/raw',
+      download: 'build-log-' + liveNode.build_log_id + '.txt',
     }, '↓ raw'),
   );
   root.append(header, pre);
 
-  liveLogEs = openBuildLogStream(running.build_log_id, pre, {
+  liveLogEs = openBuildLogStream(liveNode.build_log_id, pre, {
     onDone: (status) => {
       liveLogDone = true;
       badge.className = 'rebuild-live-log-badge ' + (status === 'ok' ? 'rll-ok' : 'rll-fail');
diff --git a/frontend/packages/dashboard/src/system-sections.css b/frontend/packages/dashboard/src/system-sections.css
index 480eb0c9..019b9216 100644
--- a/frontend/packages/dashboard/src/system-sections.css
+++ b/frontend/packages/dashboard/src/system-sections.css
@@ -134,6 +134,33 @@
 .rqe-source-approval { color: var(--green); border-color: var(--green); }
 .rqe-when { color: var(--muted); font-size: 0.85em; }
 .rqe-reason { color: var(--muted); font-size: 0.85em; flex: 1 1 auto; }
+/* Per-node DAG chain: one chip per primitive node, dependency order. */
+.rqe-nodes {
+  flex-basis: 100%;
+  margin: 0.15em 0 0 1.8em;
+  font-size: 0.85em;
+  display: flex;
+  flex-wrap: wrap;
+  align-items: baseline;
+  gap: 0.15em;
+}
+.rqe-node {
+  padding: 0.05em 0.45em;
+  border: 1px solid var(--border);
+  border-radius: 0.7em;
+  color: var(--muted);
+  white-space: nowrap;
+}
+.rqe-node-running {
+  color: var(--purple);
+  border-color: var(--purple);
+  animation: badge-pulse 1.6s ease-in-out infinite;
+}
+.rqe-node-done { color: var(--green); border-color: color-mix(in srgb, var(--green) 45%, transparent); }
+.rqe-node-failed { color: var(--red); border-color: var(--red); }
+.rqe-node-cancelled { opacity: 0.55; text-decoration: line-through; }
+.rqe-node-arrow { color: var(--muted); }
+.rqe-node-log { margin-left: 0.1em; text-decoration: none; }
 .rqe-step {
   flex-basis: 100%;
   margin: 0.1em 0 0 1.8em;
diff --git a/nix/modules/hive-c0re.nix b/nix/modules/hive-c0re.nix
index 451a5a46..8d748f8f 100644
--- a/nix/modules/hive-c0re.nix
+++ b/nix/modules/hive-c0re.nix
@@ -52,6 +52,7 @@ let
     agent_cpu_quota = cfg.agentCpuQuota;
     agent_memory_max = cfg.agentMemoryMax;
     model_prices = cfg.modelPrices;
+    build_slots = cfg.buildSlots;
   };
 
   # Stylix theme integration (zero-op auto-detect). When the operator's
@@ -771,6 +772,22 @@ in
         `"2G"`.
       '';
     };
+
+    buildSlots = lib.mkOption {
+      type = lib.types.ints.positive;
+      default = 1;
+      example = 2;
+      description = ''
+        Number of nix-heavy job-queue nodes (container prebuilds,
+        profile swaps, first-spawn creates, meta lock bumps) hive-c0re
+        runs concurrently. The default of 1 serializes all heavy nix
+        work like the pre-DAG rebuild queue did; raise it on hosts with
+        the cores/RAM to build several agent toplevels at once.
+        Per-agent correctness is independent of this count — each
+        agent's container-affecting operations are serialized by its
+        lifecycle lease regardless.
+      '';
+    };
   };
 
   config = lib.mkIf cfg.enable {