diff --git a/.github/workflows/ci.yml b/.github/workflows/ci.yml
index 29c6973..a6466f8 100644
--- a/.github/workflows/ci.yml
+++ b/.github/workflows/ci.yml
@@ -35,6 +35,9 @@ jobs:
       # rather than only at release time: a manifest that cannot be published should fail in the PR
       # that broke it, not in the workflow_dispatch someone runs three weeks later.
       - run: pnpm release:preflight
+      # Packaging breaks silently: `files`/`exports`/build-output drift is invisible to a suite
+      # that imports `src/`. Catch it in the PR, not in an immutable publish.
+      - run: pnpm verify:package
 
   determinism-gate:
     # Static half of the determinism guarantee (SSOT «Инварианты ядра» §2): no wall clock, no
diff --git a/.github/workflows/release.yml b/.github/workflows/release.yml
index 389a0b6..86fb591 100644
--- a/.github/workflows/release.yml
+++ b/.github/workflows/release.yml
@@ -95,6 +95,12 @@ jobs:
       - name: Build dist
         run: pnpm build
 
+      - name: Clean-consumer gate (the tarball, not the repo)
+        # The suite imports `src/`; consumers get the TARBALL. They drift whenever `files`,
+        # `exports` or the build output move — a package can be fully green in-repo and still
+        # install into a broken import. Proven here BEFORE publish, because npm is immutable.
+        run: pnpm verify:package
+
       - name: Publish to npm (with provenance)
         run: pnpm publish --access public --no-git-checks
         env:
diff --git a/package.json b/package.json
index 041015f..87d22fe 100644
--- a/package.json
+++ b/package.json
@@ -15,7 +15,8 @@
     }
   },
   "files": [
-    "dist"
+    "dist",
+    "NOTICE"
   ],
   "publishConfig": {
     "access": "public",
@@ -29,7 +30,8 @@
     "gate:tapes": "tsx scripts/tape-integrity.ts",
     "release:preflight": "node scripts/assert-version-publishable.mjs",
     "gate:refresh": "tsx scripts/refresh-expectations.ts",
-    "tapes:build": "tsx scripts/build-tapes.ts"
+    "tapes:build": "tsx scripts/build-tapes.ts",
+    "verify:package": "node scripts/verify-package.mjs"
   },
   "dependencies": {
     "@trdlabs/sdk": "0.13.0",
diff --git a/scripts/verify-package.mjs b/scripts/verify-package.mjs
new file mode 100644
index 0000000..9460341
--- /dev/null
+++ b/scripts/verify-package.mjs
@@ -0,0 +1,94 @@
+#!/usr/bin/env node
+// Clean-consumer gate — port of the check the initiative's «Environment / operations prerequisites»
+// names (backtester `verify-sdk-package.ts`, recommended by analysis doc 07).
+//
+// What it proves that the test suite cannot: the suite imports `src/`, but consumers get the
+// TARBALL. Those differ whenever `files`, `exports`, or the build output drift — a package can be
+// fully green in-repo and still install into a broken import. So this packs the real artifact,
+// installs it into a throwaway project OUTSIDE the workspace (no hoisting, no workspace links to
+// paper over a missing dependency), imports it through its public entrypoint, and runs an actual
+// `simulate()`.
+//
+// Run: node scripts/verify-package.mjs
+
+import { execFileSync } from 'node:child_process';
+import { mkdtempSync, readFileSync, rmSync, writeFileSync } from 'node:fs';
+import { tmpdir } from 'node:os';
+import { join, resolve } from 'node:path';
+import { fileURLToPath } from 'node:url';
+
+const ROOT = resolve(fileURLToPath(new URL('..', import.meta.url)));
+const pkg = JSON.parse(readFileSync(join(ROOT, 'package.json'), 'utf8'));
+const problems = [];
+
+const run = (cmd, args, cwd) =>
+  execFileSync(cmd, args, { cwd, encoding: 'utf8', stdio: ['ignore', 'pipe', 'pipe'] });
+
+const work = mkdtempSync(join(tmpdir(), 'engine-consumer-'));
+try {
+  run('pnpm', ['build'], ROOT);
+  run('pnpm', ['pack', '--pack-destination', work], ROOT);
+  const tarball = join(work, `trdlabs-engine-${pkg.version}.tgz`);
+
+  // ── Contents the licence and the entrypoint require ────────────────────────
+  const listed = run('tar', ['-tzf', tarball])
+    .split('\n')
+    .map((l) => l.replace(/^package\//, '').trim())
+    .filter(Boolean);
+
+  for (const required of ['dist/index.js', 'dist/index.d.ts', 'LICENSE', 'NOTICE']) {
+    if (!listed.includes(required)) problems.push(`tarball is missing ${required}`);
+  }
+  // Apache-2.0 §4(d): a distribution of a work that carries a NOTICE file must carry it along.
+  // Easy to lose, because `files: ["dist"]` only auto-includes LICENSE and README.
+
+  // ── The artifact as a consumer actually receives it ────────────────────────
+  const project = join(work, 'consumer');
+  run('mkdir', ['-p', project]);
+  writeFileSync(
+    join(project, 'package.json'),
+    JSON.stringify(
+      { name: 'engine-clean-consumer', private: true, type: 'module', dependencies: { '@trdlabs/engine': `file:${tarball}` } },
+      null,
+      2,
+    ),
+  );
+  run('pnpm', ['install', '--ignore-workspace', '--no-frozen-lockfile'], project);
+
+  // A real run, not just an import: an entrypoint that resolves but throws on first use is still a
+  // broken release.
+  const smoke = `
+    import { simulate, STANDARD_NO_FUNDING_1, ENGINE_VERSION } from '@trdlabs/engine';
+    const trace = simulate({
+      runId: 'clean-consumer-smoke',
+      seed: 1,
+      tape: { symbol: 'BTCUSDT', timeframe: '1m', bars: [
+        { ts: 1, open: 100, high: 101, low: 99, close: 100, volume: 1 },
+        { ts: 2, open: 100, high: 101, low: 99, close: 100, volume: 1 },
+      ] },
+      strategy: { id: 'always_flat', version: '1', onBarClose: () => ({ kind: 'idle' }) },
+      riskProfile: { id: 'r', version: '1', maxConcurrentPositions: 1,
+        exposureLimits: { maxPositionNotionalPct: 1 }, allowedSides: ['long'],
+        sizing: { kind: 'fixed_usd', usd: 100 } },
+      realityModel: STANDARD_NO_FUNDING_1,
+      initialEquity: 1000,
+    });
+    if (trace.engineVersion !== ENGINE_VERSION) throw new Error('trace does not carry ENGINE_VERSION');
+    if (trace.summary.barsProcessed !== 2) throw new Error('simulate() did not process the tape');
+    console.log('clean consumer: import + simulate() OK');
+  `;
+  writeFileSync(join(project, 'smoke.mjs'), smoke);
+  process.stdout.write(run('node', ['smoke.mjs'], project));
+} catch (err) {
+  problems.push(`clean-consumer run failed: ${err.stderr?.toString().trim() || err.message}`);
+} finally {
+  rmSync(work, { recursive: true, force: true });
+}
+
+if (problems.length > 0) {
+  console.error('clean-consumer gate: FAILED\n');
+  for (const p of problems) console.error(`  - ${p}`);
+  process.exit(1);
+}
+
+console.log(`clean-consumer gate: @trdlabs/engine@${pkg.version} installs and runs from its tarball`);