diff --git a/metrics-shim.cjs b/metrics-shim.cjs
new file mode 100644
index 00000000..3e6309bc
--- /dev/null
+++ b/metrics-shim.cjs
@@ -0,0 +1,45 @@
+'use strict';
+// Prometheus metrics shim — preloaded into the Indiekit process via:
+//   node --require ./metrics-shim.cjs <indiekit cli>
+// Because it runs inside the same process, all metrics (heap, GC, event
+// loop lag, CPU, open handles) reflect the actual Indiekit application.
+//
+// Grafana dashboards: NodeJS Application Dashboard (11159) at
+//   https://console.giersig.eu
+//
+// Config via environment variables (set in .env):
+//   METRICS_BIND_HOST  — defaults to 0.0.0.0
+//   METRICS_PORT       — defaults to 9209
+
+const http = require('http');
+const client = require('prom-client');
+
+const register = new client.Registry();
+client.collectDefaultMetrics({ register });
+
+const host = process.env.METRICS_BIND_HOST || '0.0.0.0';
+const port = parseInt(process.env.METRICS_PORT || '9209', 10);
+
+const server = http.createServer(async (req, res) => {
+  if (req.url === '/metrics') {
+    try {
+      const metrics = await register.metrics();
+      res.setHeader('Content-Type', register.contentType);
+      res.end(metrics);
+    } catch (err) {
+      res.writeHead(500);
+      res.end(String(err));
+    }
+  } else {
+    res.writeHead(404);
+    res.end('Not found\n');
+  }
+});
+
+server.listen(port, host, () => {
+  process.stderr.write(`[metrics] Prometheus metrics at http://${host}:${port}/metrics\n`);
+});
+
+server.on('error', (err) => {
+  process.stderr.write(`[metrics] Server error: ${err.message}\n`);
+});
diff --git a/package-lock.json b/package-lock.json
index 374c5609..0bba259e 100644
--- a/package-lock.json
+++ b/package-lock.json
@@ -39,7 +39,8 @@
         "@rmdes/indiekit-syndicator-indienews": "^1.0.1",
         "dotenv": "^17.3.1",
         "mongodb": "^7.1.0",
-        "node-gyp": "^12.2.0"
+        "node-gyp": "^12.2.0",
+        "prom-client": "^15.1.3"
       }
     },
     "node_modules/@accessible-components/tag-input": {
@@ -2417,8 +2418,8 @@
       }
     },
     "node_modules/@rmdes/indiekit-endpoint-activitypub": {
-      "version": "3.10.0",
-      "resolved": "git+ssh://git@github.com/svemagie/indiekit-endpoint-activitypub.git#b54146ce5b1d1eed1003ca2d046e746e90381b43",
+      "version": "3.10.3",
+      "resolved": "git+ssh://git@github.com/svemagie/indiekit-endpoint-activitypub.git#318720c90d123a6b5b57b689eca2b15f264dfd79",
       "license": "MIT",
       "dependencies": {
         "@fedify/debugger": "^2.1.0",
@@ -3552,6 +3553,12 @@
         "node": ">= 18"
       }
     },
+    "node_modules/bintrees": {
+      "version": "1.0.2",
+      "resolved": "https://registry.npmjs.org/bintrees/-/bintrees-1.0.2.tgz",
+      "integrity": "sha512-VOMgTMwjAaUG580SXn3LacVgjurrbMme7ZZNYGSSV7mmtY6QQRh0Eg3pwIcntQ77DErK1L0NxkbetjcoXzVwKw==",
+      "license": "MIT"
+    },
     "node_modules/body-parser": {
       "version": "2.2.2",
       "resolved": "https://registry.npmjs.org/body-parser/-/body-parser-2.2.2.tgz",
@@ -7389,6 +7396,19 @@
       "integrity": "sha512-3ouUOpQhtgrbOa17J7+uxOTpITYWaGP7/AhoR3+A+/1e9skrzelGi/dXzEYyvbxubEF6Wn2ypscTKiKJFFn1ag==",
       "license": "MIT"
     },
+    "node_modules/prom-client": {
+      "version": "15.1.3",
+      "resolved": "https://registry.npmjs.org/prom-client/-/prom-client-15.1.3.tgz",
+      "integrity": "sha512-6ZiOBfCywsD4k1BN9IX0uZhF+tJkV8q8llP64G5Hajs4JOeVLPCwpPVcpXy3BwYiUGgyJzsJJQeOIv7+hDSq8g==",
+      "license": "Apache-2.0",
+      "dependencies": {
+        "@opentelemetry/api": "^1.4.0",
+        "tdigest": "^0.1.1"
+      },
+      "engines": {
+        "node": "^16 || ^18 || >=20"
+      }
+    },
     "node_modules/proxy-addr": {
       "version": "2.0.7",
       "resolved": "https://registry.npmjs.org/proxy-addr/-/proxy-addr-2.0.7.tgz",
@@ -8290,6 +8310,15 @@
         "node": ">=18"
       }
     },
+    "node_modules/tdigest": {
+      "version": "0.1.2",
+      "resolved": "https://registry.npmjs.org/tdigest/-/tdigest-0.1.2.tgz",
+      "integrity": "sha512-+G0LLgjjo9BZX2MfdvPfH+MKLCrxlXSYec5DaPYP1fe6Iyhf0/fSmJ0bFiZ1F8BT6cGXl2LpltQptzjXKWEkKA==",
+      "license": "MIT",
+      "dependencies": {
+        "bintrees": "1.0.2"
+      }
+    },
     "node_modules/tinyglobby": {
       "version": "0.2.15",
       "resolved": "https://registry.npmjs.org/tinyglobby/-/tinyglobby-0.2.15.tgz",
diff --git a/package.json b/package.json
index 0d57802a..24f4edde 100644
--- a/package.json
+++ b/package.json
@@ -4,8 +4,8 @@
   "description": "",
   "main": "index.js",
   "scripts": {
-    "postinstall": "xattr -w com.apple.fileprovider.ignore#P 1 node_modules 2>/dev/null || true && node scripts/patch-lightningcss.mjs && node scripts/patch-endpoint-media-scope.mjs && node scripts/patch-endpoint-media-sharp-runtime.mjs && node scripts/patch-frontend-sharp-runtime.mjs && node scripts/patch-endpoint-files-upload-route.mjs && node scripts/patch-endpoint-files-upload-locales.mjs && node scripts/patch-endpoint-activitypub-locales.mjs && node scripts/patch-endpoint-homepage-locales.mjs && node scripts/patch-endpoint-homepage-identity-defaults.mjs && node scripts/patch-federation-unlisted-guards.mjs && node scripts/patch-endpoint-micropub-where-note-visibility.mjs && node scripts/patch-endpoint-podroll-opml-upload.mjs && node scripts/patch-frontend-serviceworker-file.mjs && node scripts/patch-endpoint-comments-locales.mjs && node scripts/patch-endpoint-posts-locales.mjs && node scripts/patch-endpoint-conversations-locales.mjs && node scripts/patch-conversations-collection-guards.mjs && node scripts/patch-indiekit-routes-rate-limits.mjs && node scripts/patch-indiekit-error-production-stack.mjs && node scripts/patch-indieauth-devmode-guard.mjs && node scripts/patch-listening-endpoint-runtime-guards.mjs && node scripts/patch-endpoint-github-changelog-categories.mjs && node scripts/patch-endpoint-github-contributions-log.mjs && node scripts/patch-endpoint-blogroll-feeds-alias.mjs && node scripts/patch-endpoint-posts-uid-lookup.mjs && node scripts/patch-conversations-bluesky-self-filter.mjs && node scripts/patch-conversations-bluesky-cursor-fix.mjs && node scripts/patch-endpoint-micropub-source-filter.mjs && node scripts/patch-syndicate-force-checked-default.mjs && node scripts/patch-syndicate-normalize-syndication-array.mjs && node scripts/patch-endpoint-posts-fetch-diagnostic.mjs && node scripts/patch-micropub-fetch-internal-url.mjs && node scripts/patch-micropub-session-token.mjs && node scripts/patch-indiekit-endpoint-urls-protocol.mjs && node scripts/patch-webmention-sender-hentry-syntax.mjs && node scripts/patch-webmention-sender-retry.mjs && node scripts/patch-webmention-sender-livefetch.mjs && node scripts/patch-webmention-sender-empty-details.mjs && node scripts/patch-bluesky-syndicator-internal-url.mjs && node scripts/patch-ap-skip-draft-syndication.mjs && node scripts/patch-ap-og-image.mjs && node scripts/patch-ap-webfinger-before-auth.mjs",
-    "serve": "export NODE_ENV=${NODE_ENV:-production} INDIEKIT_DEBUG=${INDIEKIT_DEBUG:-0} && node scripts/preflight-production-security.mjs && node scripts/preflight-mongo-connection.mjs && node scripts/preflight-activitypub-rsa-key.mjs && node scripts/preflight-activitypub-profile-urls.mjs && node scripts/patch-lightningcss.mjs && node scripts/patch-endpoint-media-scope.mjs && node scripts/patch-endpoint-media-sharp-runtime.mjs && node scripts/patch-frontend-sharp-runtime.mjs && node scripts/patch-endpoint-files-upload-route.mjs && node scripts/patch-endpoint-files-upload-locales.mjs && node scripts/patch-endpoint-activitypub-locales.mjs && node scripts/patch-endpoint-homepage-locales.mjs && node scripts/patch-endpoint-homepage-identity-defaults.mjs && node scripts/patch-federation-unlisted-guards.mjs && node scripts/patch-endpoint-micropub-where-note-visibility.mjs && node scripts/patch-endpoint-podroll-opml-upload.mjs && node scripts/patch-frontend-serviceworker-file.mjs && node scripts/patch-endpoint-comments-locales.mjs && node scripts/patch-endpoint-posts-locales.mjs && node scripts/patch-endpoint-conversations-locales.mjs && node scripts/patch-conversations-collection-guards.mjs && node scripts/patch-indiekit-routes-rate-limits.mjs && node scripts/patch-indiekit-error-production-stack.mjs && node scripts/patch-indieauth-devmode-guard.mjs && node scripts/patch-listening-endpoint-runtime-guards.mjs && node scripts/patch-endpoint-github-changelog-categories.mjs && node scripts/patch-endpoint-github-contributions-log.mjs && node scripts/patch-microsub-reader-ap-dispatch.mjs && node scripts/patch-microsub-compose-draft-guard.mjs && node scripts/patch-endpoint-blogroll-feeds-alias.mjs && node scripts/patch-endpoint-posts-uid-lookup.mjs && node scripts/patch-conversations-bluesky-self-filter.mjs && node scripts/patch-conversations-bluesky-cursor-fix.mjs && node scripts/patch-endpoint-micropub-source-filter.mjs && node scripts/patch-syndicate-force-checked-default.mjs && node scripts/patch-syndicate-normalize-syndication-array.mjs && node scripts/patch-endpoint-posts-fetch-diagnostic.mjs && node scripts/patch-micropub-fetch-internal-url.mjs && node scripts/patch-micropub-session-token.mjs && node scripts/patch-indiekit-endpoint-urls-protocol.mjs && node scripts/patch-webmention-sender-hentry-syntax.mjs && node scripts/patch-webmention-sender-retry.mjs && node scripts/patch-webmention-sender-livefetch.mjs && node scripts/patch-webmention-sender-empty-details.mjs && node scripts/patch-bluesky-syndicator-internal-url.mjs && node scripts/patch-ap-skip-draft-syndication.mjs && node scripts/patch-ap-og-image.mjs && node scripts/patch-ap-webfinger-before-auth.mjs && node node_modules/@indiekit/indiekit/bin/cli.js serve --config indiekit.config.mjs",
+    "postinstall": "xattr -w com.apple.fileprovider.ignore#P 1 node_modules 2>/dev/null || true && node scripts/patch-lightningcss.mjs && node scripts/patch-endpoint-media-scope.mjs && node scripts/patch-endpoint-media-sharp-runtime.mjs && node scripts/patch-frontend-sharp-runtime.mjs && node scripts/patch-endpoint-files-upload-route.mjs && node scripts/patch-endpoint-files-upload-locales.mjs && node scripts/patch-endpoint-activitypub-locales.mjs && node scripts/patch-endpoint-homepage-locales.mjs && node scripts/patch-endpoint-homepage-identity-defaults.mjs && node scripts/patch-federation-unlisted-guards.mjs && node scripts/patch-endpoint-micropub-where-note-visibility.mjs && node scripts/patch-endpoint-podroll-opml-upload.mjs && node scripts/patch-frontend-serviceworker-file.mjs && node scripts/patch-endpoint-comments-locales.mjs && node scripts/patch-endpoint-posts-locales.mjs && node scripts/patch-endpoint-conversations-locales.mjs && node scripts/patch-conversations-collection-guards.mjs && node scripts/patch-indiekit-routes-rate-limits.mjs && node scripts/patch-indiekit-error-production-stack.mjs && node scripts/patch-indieauth-devmode-guard.mjs && node scripts/patch-listening-endpoint-runtime-guards.mjs && node scripts/patch-endpoint-github-changelog-categories.mjs && node scripts/patch-endpoint-github-contributions-log.mjs && node scripts/patch-endpoint-blogroll-feeds-alias.mjs && node scripts/patch-endpoint-posts-uid-lookup.mjs && node scripts/patch-conversations-bluesky-self-filter.mjs && node scripts/patch-conversations-bluesky-cursor-fix.mjs && node scripts/patch-endpoint-micropub-source-filter.mjs && node scripts/patch-syndicate-force-checked-default.mjs && node scripts/patch-syndicate-normalize-syndication-array.mjs && node scripts/patch-endpoint-posts-fetch-diagnostic.mjs && node scripts/patch-micropub-fetch-internal-url.mjs && node scripts/patch-micropub-session-token.mjs && node scripts/patch-indiekit-endpoint-urls-protocol.mjs && node scripts/patch-webmention-sender-hentry-syntax.mjs && node scripts/patch-webmention-sender-retry.mjs && node scripts/patch-webmention-sender-livefetch.mjs && node scripts/patch-webmention-sender-empty-details.mjs && node scripts/patch-bluesky-syndicator-internal-url.mjs && node scripts/patch-ap-skip-draft-syndication.mjs",
+    "serve": "export NODE_ENV=${NODE_ENV:-production} INDIEKIT_DEBUG=${INDIEKIT_DEBUG:-0} && node scripts/preflight-production-security.mjs && node scripts/preflight-mongo-connection.mjs && node scripts/preflight-activitypub-rsa-key.mjs && node scripts/preflight-activitypub-profile-urls.mjs && node scripts/patch-lightningcss.mjs && node scripts/patch-endpoint-media-scope.mjs && node scripts/patch-endpoint-media-sharp-runtime.mjs && node scripts/patch-frontend-sharp-runtime.mjs && node scripts/patch-endpoint-files-upload-route.mjs && node scripts/patch-endpoint-files-upload-locales.mjs && node scripts/patch-endpoint-activitypub-locales.mjs && node scripts/patch-endpoint-homepage-locales.mjs && node scripts/patch-endpoint-homepage-identity-defaults.mjs && node scripts/patch-federation-unlisted-guards.mjs && node scripts/patch-endpoint-micropub-where-note-visibility.mjs && node scripts/patch-endpoint-podroll-opml-upload.mjs && node scripts/patch-frontend-serviceworker-file.mjs && node scripts/patch-endpoint-comments-locales.mjs && node scripts/patch-endpoint-posts-locales.mjs && node scripts/patch-endpoint-conversations-locales.mjs && node scripts/patch-conversations-collection-guards.mjs && node scripts/patch-indiekit-routes-rate-limits.mjs && node scripts/patch-indiekit-error-production-stack.mjs && node scripts/patch-indieauth-devmode-guard.mjs && node scripts/patch-listening-endpoint-runtime-guards.mjs && node scripts/patch-endpoint-github-changelog-categories.mjs && node scripts/patch-endpoint-github-contributions-log.mjs && node scripts/patch-microsub-reader-ap-dispatch.mjs && node scripts/patch-microsub-compose-draft-guard.mjs && node scripts/patch-endpoint-blogroll-feeds-alias.mjs && node scripts/patch-endpoint-posts-uid-lookup.mjs && node scripts/patch-conversations-bluesky-self-filter.mjs && node scripts/patch-conversations-bluesky-cursor-fix.mjs && node scripts/patch-endpoint-micropub-source-filter.mjs && node scripts/patch-syndicate-force-checked-default.mjs && node scripts/patch-syndicate-normalize-syndication-array.mjs && node scripts/patch-endpoint-posts-fetch-diagnostic.mjs && node scripts/patch-micropub-fetch-internal-url.mjs && node scripts/patch-micropub-session-token.mjs && node scripts/patch-indiekit-endpoint-urls-protocol.mjs && node scripts/patch-webmention-sender-hentry-syntax.mjs && node scripts/patch-webmention-sender-retry.mjs && node scripts/patch-webmention-sender-livefetch.mjs && node scripts/patch-webmention-sender-empty-details.mjs && node scripts/patch-bluesky-syndicator-internal-url.mjs && node scripts/patch-ap-skip-draft-syndication.mjs && node --require ./metrics-shim.cjs node_modules/@indiekit/indiekit/bin/cli.js serve --config indiekit.config.mjs",
     "test": "echo \"Error: no test specified\" && exit 1"
   },
   "keywords": [],
@@ -51,6 +51,7 @@
     "@rmdes/indiekit-syndicator-indienews": "^1.0.1",
     "dotenv": "^17.3.1",
     "mongodb": "^7.1.0",
-    "node-gyp": "^12.2.0"
+    "node-gyp": "^12.2.0",
+    "prom-client": "^15.1.3"
   }
 }
diff --git a/start.example.sh b/start.example.sh
index 022344c9..e8aa0b8f 100644
--- a/start.example.sh
+++ b/start.example.sh
@@ -57,7 +57,7 @@ for patch in scripts/patch-*.mjs; do
   "${NODE_BIN}" "$patch"
 done
 
-"${NODE_BIN}" node_modules/@indiekit/indiekit/bin/cli.js serve --config indiekit.config.mjs &
+"${NODE_BIN}" --require ./metrics-shim.cjs node_modules/@indiekit/indiekit/bin/cli.js serve --config indiekit.config.mjs &
 INDIEKIT_PID="$!"
 
 # Webmention sender — polls every N seconds (see @rmdes/indiekit-endpoint-webmention-sender README)