triggerdotdev · nicktrn · Jun 5, 2026 · Jun 4, 2026 · Jun 4, 2026 · Jun 4, 2026
diff --git a/.changeset/backpressure-scale-up-freeze.md b/.changeset/backpressure-scale-up-freeze.md
@@ -0,0 +1,5 @@
+---
+"@trigger.dev/core": patch
+---
+
+Add optional `shouldPauseScaling` to the supervisor consumer pool scaling options to freeze scale-up while it returns true (scale-down stays allowed).
diff --git a/.server-changes/supervisor-dequeue-backpressure.md b/.server-changes/supervisor-dequeue-backpressure.md
@@ -0,0 +1,6 @@
+---
+area: supervisor
+type: feature
+---
+
+Add opt-in dequeue backpressure to the supervisor. When enabled, the supervisor reads a verdict from Redis and pauses dequeuing while the worker cluster is saturated, then resumes once capacity is available. Disabled by default - no behavior change for existing deployments.
diff --git a/apps/supervisor/package.json b/apps/supervisor/package.json
@@ -18,13 +18,15 @@
    "@kubernetes/client-node": "^1.0.0",
    "@trigger.dev/core": "workspace:*",
    "dockerode": "^4.0.6",
+    "ioredis": "^5.3.2",
    "p-limit": "^6.2.0",
    "prom-client": "^15.1.0",
    "socket.io": "4.7.4",
    "std-env": "^3.8.0",
    "zod": "3.25.76"
  },
  "devDependencies": {
+    "@internal/testcontainers": "workspace:*",
    "@types/dockerode": "^3.3.33"
  }
 }
diff --git a/apps/supervisor/src/backpressure/backpressureMetrics.ts b/apps/supervisor/src/backpressure/backpressureMetrics.ts
@@ -0,0 +1,34 @@
+import { Counter, Gauge, type Registry } from "prom-client";
+
+/** Prometheus metrics for dequeue backpressure. */
+export class BackpressureMetrics {
+  /** 1 while backpressure is engaged (computed signal, set even in dry-run). */
+  readonly engaged: Gauge<string>;
+  /** 1 when running in dry-run (gates inert). */
+  readonly dryRun: Gauge<string>;
+  /** Dequeue attempts the gate skipped - or would have, in dry-run (labelled). */
+  readonly skipsTotal: Counter<string>;
+
+  constructor(opts: { register: Registry; prefix?: string }) {
+    const prefix = opts.prefix ?? "supervisor_backpressure";
+
+    this.engaged = new Gauge({
+      name: `${prefix}_engaged`,
+      help: "1 while dequeue backpressure is engaged (computed signal, regardless of dry-run)",
+      registers: [opts.register],
+    });
+
+    this.dryRun = new Gauge({
+      name: `${prefix}_dry_run`,
+      help: "1 when dequeue backpressure is in dry-run mode (gates inert)",
+      registers: [opts.register],
+    });
+
+    this.skipsTotal = new Counter({
+      name: `${prefix}_skipped_dequeues_total`,
+      help: "Dequeue attempts skipped by backpressure (or would be, in dry-run)",
+      labelNames: ["dry_run"],
+      registers: [opts.register],
+    });
+  }
+}