diff --git a/pnpm11/pnpm/test/install/memoryBounded.ts b/pnpm11/pnpm/test/install/memoryBounded.ts
new file mode 100644
index 0000000000..9e52cc58b1
--- /dev/null
+++ b/pnpm11/pnpm/test/install/memoryBounded.ts
@@ -0,0 +1,98 @@
+import http from 'node:http'
+import type { AddressInfo } from 'node:net'
+
+import { expect, test } from '@jest/globals'
+import { prepare } from '@pnpm/prepare'
+
+import { execPnpm } from '../utils/index.js'
+
+const PACKAGE_COUNT = 40
+const JUNK_BYTES = 6 * 1024 * 1024
+
+/**
+ * End-to-end regression guard for https://github.com/pnpm/pnpm/issues/8441:
+ * a whole `pnpm install` (the bundled CLI, not just the resolver package)
+ * must not retain full-document bulk, so it completes inside a small heap.
+ *
+ * The registry documents — served by a local server, one per optional
+ * dependency so the CLI fetches full metadata — each carry 6 MB of
+ * install-irrelevant bulk, 240 MB total. Retaining the parsed documents,
+ * as the resolver did before condensing, overflows the 256 MB cap by
+ * ~100 MB regardless of which cache pins them; the condensed working set
+ * plus the CLI's baseline fits with roughly 100 MB to spare (the fixed
+ * install passes even a 192 MB cap). That margin in both directions keeps the
+ * guard deterministic rather than timing-sensitive.
+ */
+test('install --lockfile-only completes within a small heap while registry documents carry megabytes of bulk', async () => {
+  const server = await startBloatedRegistry()
+  const optionalDependencies = Object.fromEntries(
+    Array.from({ length: PACKAGE_COUNT }, (_, i) => [`bloated-pkg-${i}`, '1.0.0'])
+  )
+  const project = prepare({ optionalDependencies })
+
+  try {
+    await execPnpm(['install', '--lockfile-only'], {
+      env: {
+        NODE_OPTIONS: '--max-old-space-size=256',
+        pnpm_config_registry: server.url,
+        // Bounds the post-fix transient footprint (response body + freshly
+        // parsed document per in-flight request) so the heap cap measures
+        // what is RETAINED across the resolution, which no concurrency
+        // setting can shrink.
+        pnpm_config_network_concurrency: '4',
+      },
+    })
+  } finally {
+    server.close()
+  }
+
+  const lockfile = project.readLockfile()
+  expect(Object.keys(lockfile.packages)).toHaveLength(PACKAGE_COUNT)
+  expect(lockfile.packages['bloated-pkg-0@1.0.0'].libc).toEqual(['glibc'])
+})
+
+interface BloatedRegistry {
+  url: string
+  close: () => void
+}
+
+// Serves a full packument for any package name requested. The junk string is
+// shared server-side; JSON.parse in the CLI gives each document its own copy —
+// the copy whose retention this test bounds. Tarball URLs point back at this
+// server but are never fetched: --lockfile-only resolves without downloading.
+async function startBloatedRegistry (): Promise<BloatedRegistry> {
+  const junk = 'x'.repeat(JUNK_BYTES / 2)
+  const server = http.createServer((req, res) => {
+    const name = decodeURIComponent((req.url ?? '').slice(1))
+    res.setHeader('content-type', 'application/json')
+    res.end(JSON.stringify({
+      name,
+      'dist-tags': { latest: '1.0.0' },
+      versions: {
+        '1.0.0': {
+          name,
+          version: '1.0.0',
+          libc: ['glibc'],
+          description: junk,
+          dist: {
+            tarball: `${registryUrl()}${name}/-/${name}-1.0.0.tgz`,
+            integrity: 'sha512-AAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAA==',
+          },
+        },
+      },
+      readme: junk,
+    }))
+  })
+  await new Promise<void>((resolve) => {
+    server.listen(0, '127.0.0.1', resolve)
+  })
+  function registryUrl (): string {
+    return `http://127.0.0.1:${(server.address() as AddressInfo).port}/`
+  }
+  return {
+    url: registryUrl(),
+    close: () => {
+      server.close()
+    },
+  }
+}