diff --git a/sdk/package-lock.json b/sdk/package-lock.json
index b905dd02..44ace6f1 100644
--- a/sdk/package-lock.json
+++ b/sdk/package-lock.json
@@ -8,12 +8,14 @@
       "name": "@relayflows/sdk",
       "version": "0.1.0",
       "license": "UNLICENSED",
-      "bin": {
-        "flows": "dist/cli.js"
-      },
       "dependencies": {
+        "@types/js-yaml": "^4.0.9",
+        "js-yaml": "^5.4.1",
         "yaml": "^2.5.1"
       },
+      "bin": {
+        "flows": "dist/cli.js"
+      },
       "devDependencies": {
         "@types/node": "^22.7.0",
         "typescript": "^5.6.0",
@@ -792,6 +794,12 @@
       "dev": true,
       "license": "MIT"
     },
+    "node_modules/@types/js-yaml": {
+      "version": "4.0.9",
+      "resolved": "https://registry.npmjs.org/@types/js-yaml/-/js-yaml-4.0.9.tgz",
+      "integrity": "sha512-k4MGaQl5TGo/iipqb2UDG2UwjXziSWkh0uysQelTlJpX1qGlpUZYm8PnO4DxG1qBomtJUdYJ6qR6xdIah10JLg==",
+      "license": "MIT"
+    },
     "node_modules/@types/node": {
       "version": "22.20.1",
       "resolved": "https://registry.npmjs.org/@types/node/-/node-22.20.1.tgz",
@@ -915,6 +923,12 @@
         "url": "https://opencollective.com/vitest"
       }
     },
+    "node_modules/argparse": {
+      "version": "2.0.1",
+      "resolved": "https://registry.npmjs.org/argparse/-/argparse-2.0.1.tgz",
+      "integrity": "sha512-8+9WqebbFzpX9OR+Wa6O29asIogeRMzcGtAINdpMHHyAg10f05aSFVBbcEqGf/PXw1EjAZ+q2/bEBg3DvurK3Q==",
+      "license": "Python-2.0"
+    },
     "node_modules/assertion-error": {
       "version": "2.0.1",
       "resolved": "https://registry.npmjs.org/assertion-error/-/assertion-error-2.0.1.tgz",
@@ -1071,6 +1085,28 @@
         "node": "^8.16.0 || ^10.6.0 || >=11.0.0"
       }
     },
+    "node_modules/js-yaml": {
+      "version": "5.4.1",
+      "resolved": "https://registry.npmjs.org/js-yaml/-/js-yaml-5.4.1.tgz",
+      "integrity": "sha512-28R/k+NAjeuf7+CKlTxWZVExJGwVVLwY06DgEnOMz2gEpfNkDcD7QvyiVPT0xy0XXhU8vHsd4Ot42OOPdJG7dQ==",
+      "funding": [
+        {
+          "type": "github",
+          "url": "https://github.com/sponsors/puzrin"
+        },
+        {
+          "type": "github",
+          "url": "https://github.com/sponsors/nodeca"
+        }
+      ],
+      "license": "MIT",
+      "dependencies": {
+        "argparse": "^2.0.1"
+      },
+      "bin": {
+        "js-yaml": "bin/js-yaml.mjs"
+      }
+    },
     "node_modules/loupe": {
       "version": "3.2.1",
       "resolved": "https://registry.npmjs.org/loupe/-/loupe-3.2.1.tgz",
diff --git a/sdk/package.json b/sdk/package.json
index 5bc78998..8be48996 100644
--- a/sdk/package.json
+++ b/sdk/package.json
@@ -28,6 +28,8 @@
   "license": "UNLICENSED",
   "private": true,
   "dependencies": {
+    "@types/js-yaml": "^4.0.9",
+    "js-yaml": "^5.4.1",
     "yaml": "^2.5.1"
   },
   "devDependencies": {
diff --git a/sdk/tests/backlog-picker-flow.test.ts b/sdk/tests/backlog-picker-flow.test.ts
new file mode 100644
index 00000000..a7ad7064
--- /dev/null
+++ b/sdk/tests/backlog-picker-flow.test.ts
@@ -0,0 +1,94 @@
+import { execFileSync } from 'node:child_process';
+import { mkdtempSync, mkdirSync, readFileSync, rmSync, writeFileSync } from 'node:fs';
+import { tmpdir } from 'node:os';
+import { join } from 'node:path';
+import { load } from 'js-yaml';
+import { describe, expect, it } from 'vitest';
+
+/**
+ * The backlog-picker flow's steps must agree with each other.
+ *
+ * Originally every step re-read ops/BACKLOG.md, so if the file changed between
+ * `select-entry` and `emit-package` the emitted package would describe an entry
+ * that was never selected — a Garden reporting work it did not choose. Review
+ * flagged it (PR #20, P2) and the fix snapshots the backlog once in
+ * `read-backlog`; this test is the proof that was asked for and not delivered.
+ *
+ * It runs the flow's ACTUAL shell commands rather than a reimplementation. A
+ * test of a paraphrase would pass while the flow stayed broken.
+ */
+function stepCommands(): Record<string, string> {
+  const flowPath = join(__dirname, '..', '..', 'testdata', 'backlog-picker.flow.yaml');
+  const flow = load(readFileSync(flowPath, 'utf8')) as { steps: Array<{ id: string; command: string }> };
+  return Object.fromEntries(flow.steps.map((s) => [s.id, s.command]));
+}
+
+function run(command: string, cwd: string): string {
+  return execFileSync('sh', ['-c', command], { cwd, encoding: 'utf8' });
+}
+
+describe('backlog-picker flow', () => {
+  it('emit-package describes the entry select-entry chose, even if the backlog changes between them', () => {
+    const dir = mkdtempSync(join(tmpdir(), 'backlog-picker-'));
+    try {
+      mkdirSync(join(dir, 'ops'), { recursive: true });
+      writeFileSync(
+        join(dir, 'ops', 'BACKLOG.md'),
+        '# Backlog\n\n- **Original entry** the one that must win\n',
+      );
+
+      const steps = stepCommands();
+      run(steps['read-backlog'], dir);
+
+      const selected = run(steps['select-entry'], dir).trim();
+      expect(selected).toContain('Original entry');
+
+      // The backlog changes underneath the flow, mid-run.
+      writeFileSync(
+        join(dir, 'ops', 'BACKLOG.md'),
+        '# Backlog\n\n- **Swapped entry** must NOT appear in the package\n',
+      );
+
+      const emitted = run(steps['emit-package'], dir);
+      expect(emitted).toContain('Original entry');
+      expect(emitted).not.toContain('Swapped entry');
+    } finally {
+      rmSync(dir, { recursive: true, force: true });
+    }
+  });
+
+  it('does not emit a stale entry left by a previous run', () => {
+    // The snapshot fix introduced shared persistent state, and shared state
+    // leaks across runs: if select-entry finds nothing actionable it exits
+    // before writing, so emit-package would happily read the PREVIOUS run's
+    // entry and present it as this run's choice. Review caught it (PR #21, P1)
+    // — a fix for cross-step disagreement that created cross-run staleness.
+    const dir = mkdtempSync(join(tmpdir(), 'backlog-picker-stale-'));
+    try {
+      mkdirSync(join(dir, 'ops'), { recursive: true });
+      const steps = stepCommands();
+
+      // Run one: a real entry, which populates the shared state.
+      writeFileSync(join(dir, 'ops', 'BACKLOG.md'), '# Backlog\n\n- **Yesterday entry** old\n');
+      run(steps['read-backlog'], dir);
+      run(steps['select-entry'], dir);
+      expect(run(steps['emit-package'], dir)).toContain('Yesterday entry');
+
+      // Run two: nothing actionable. select-entry must fail AND must not leave
+      // the previous choice behind for emit-package to pick up.
+      writeFileSync(join(dir, 'ops', 'BACKLOG.md'), '# Backlog\n\nnothing actionable today\n');
+      run(steps['read-backlog'], dir);
+      expect(() => run(steps['select-entry'], dir)).toThrow();
+
+      let emitted = '';
+      try {
+        emitted = run(steps['emit-package'], dir);
+      } catch {
+        return; // Failing outright is the correct outcome.
+      }
+      expect(emitted).not.toContain('Yesterday entry');
+    } finally {
+      rmSync(dir, { recursive: true, force: true });
+    }
+  });
+});
diff --git a/testdata/backlog-picker.flow.yaml b/testdata/backlog-picker.flow.yaml
index 037e057f..030f216b 100644
--- a/testdata/backlog-picker.flow.yaml
+++ b/testdata/backlog-picker.flow.yaml
@@ -6,14 +6,14 @@ description: Read ops/BACKLOG.md and deterministically emit its first work packa
 steps:
   - id: read-backlog
     type: deterministic
-    command: "cat ops/BACKLOG.md"
+    command: "mkdir -p .relayflow && cat ops/BACKLOG.md > .relayflow/backlog-picker-source.md"
   - id: select-entry
     type: deterministic
     dependsOn: [read-backlog]
     command: >-
-      node -e 'const fs=require("node:fs");const text=fs.readFileSync("ops/BACKLOG.md","utf8");const match=text.match(/^- \*\*(.+?)\*\*\s*(.*(?:\n  .*)*)/m);if(!match)process.exit(1);process.stdout.write(match[1])'
+      node -e 'const fs=require("node:fs");fs.rmSync(".relayflow/backlog-picker-entry.json",{force:true});const text=fs.readFileSync(".relayflow/backlog-picker-source.md","utf8");const match=text.match(/^- \*\*(.+?)\*\*\s*(.*(?:\n  .*)*)/m);if(!match)process.exit(1);const entry={title:match[1],body:match[2].replace(/\s+/g," ").trim()};fs.writeFileSync(".relayflow/backlog-picker-entry.json",JSON.stringify(entry));process.stdout.write(JSON.stringify(entry))'
   - id: emit-package
     type: deterministic
     dependsOn: [select-entry]
     command: >-
-      node -e 'const fs=require("node:fs");const text=fs.readFileSync("ops/BACKLOG.md","utf8");const match=text.match(/^- \*\*(.+?)\*\*\s*(.*(?:\n  .*)*)/m);if(!match)process.exit(1);process.stdout.write(JSON.stringify({title:match[1],description:match[2].replace(/\s+/g," ").trim(),files_in_scope:["sdk/src/preflight.ts","sdk/tests/preflight.test.ts"],gate:3}))'
+      node -e 'const fs=require("node:fs");const entry=JSON.parse(fs.readFileSync(".relayflow/backlog-picker-entry.json","utf8"));const text=entry.title+" "+entry.body;const files=[...new Set([...text.matchAll(/`([^`\s]*\/[^`]*)`/g)].map(match=>match[1]))];const gate=text.match(/\bgate[ -]?(\d+)\b/i);process.stdout.write(JSON.stringify({title:entry.title,description:entry.body,files_in_scope:files,gate:gate?Number(gate[1]):null}))'
diff --git a/testdata/backlog-picker.spec.canonical.json b/testdata/backlog-picker.spec.canonical.json
index c60298d7..874d6c1a 100644
--- a/testdata/backlog-picker.spec.canonical.json
+++ b/testdata/backlog-picker.spec.canonical.json
@@ -1 +1 @@
-{"description":"Read ops/BACKLOG.md and deterministically emit its first work package.","name":"backlog-picker","steps":[{"command":"cat ops/BACKLOG.md","depends_on":[],"id":"read-backlog","max_iterations":1,"retry":{"initial_backoff_ms":100,"jitter_percent":20,"max_backoff_ms":60000,"multiplier":2},"type":"deterministic","verification":{}},{"command":"node -e 'const fs=require(\"node:fs\");const text=fs.readFileSync(\"ops/BACKLOG.md\",\"utf8\");const match=text.match(/^- \\*\\*(.+?)\\*\\*\\s*(.*(?:\\n  .*)*)/m);if(!match)process.exit(1);process.stdout.write(match[1])'","depends_on":["read-backlog"],"id":"select-entry","max_iterations":1,"retry":{"initial_backoff_ms":100,"jitter_percent":20,"max_backoff_ms":60000,"multiplier":2},"type":"deterministic","verification":{}},{"command":"node -e 'const fs=require(\"node:fs\");const text=fs.readFileSync(\"ops/BACKLOG.md\",\"utf8\");const match=text.match(/^- \\*\\*(.+?)\\*\\*\\s*(.*(?:\\n  .*)*)/m);if(!match)process.exit(1);process.stdout.write(JSON.stringify({title:match[1],description:match[2].replace(/\\s+/g,\" \").trim(),files_in_scope:[\"sdk/src/preflight.ts\",\"sdk/tests/preflight.test.ts\"],gate:3}))'","depends_on":["select-entry"],"id":"emit-package","max_iterations":1,"retry":{"initial_backoff_ms":100,"jitter_percent":20,"max_backoff_ms":60000,"multiplier":2},"type":"deterministic","verification":{}}],"version":"0.1.0"}
+{"description":"Read ops/BACKLOG.md and deterministically emit its first work package.","name":"backlog-picker","steps":[{"command":"mkdir -p .relayflow && cat ops/BACKLOG.md > .relayflow/backlog-picker-source.md","depends_on":[],"id":"read-backlog","max_iterations":1,"retry":{"initial_backoff_ms":100,"jitter_percent":20,"max_backoff_ms":60000,"multiplier":2},"type":"deterministic","verification":{}},{"command":"node -e 'const fs=require(\"node:fs\");const text=fs.readFileSync(\".relayflow/backlog-picker-source.md\",\"utf8\");const match=text.match(/^- \\*\\*(.+?)\\*\\*\\s*(.*(?:\\n  .*)*)/m);if(!match)process.exit(1);const entry={title:match[1],body:match[2].replace(/\\s+/g,\" \").trim()};fs.writeFileSync(\".relayflow/backlog-picker-entry.json\",JSON.stringify(entry));process.stdout.write(JSON.stringify(entry))'","depends_on":["read-backlog"],"id":"select-entry","max_iterations":1,"retry":{"initial_backoff_ms":100,"jitter_percent":20,"max_backoff_ms":60000,"multiplier":2},"type":"deterministic","verification":{}},{"command":"node -e 'const fs=require(\"node:fs\");const entry=JSON.parse(fs.readFileSync(\".relayflow/backlog-picker-entry.json\",\"utf8\"));const text=entry.title+\" \"+entry.body;const files=[...new Set([...text.matchAll(/`([^`\\s]*\\/[^`]*)`/g)].map(match=>match[1]))];const gate=text.match(/\\bgate[ -]?(\\d+)\\b/i);process.stdout.write(JSON.stringify({title:entry.title,description:entry.body,files_in_scope:files,gate:gate?Number(gate[1]):null}))'","depends_on":["select-entry"],"id":"emit-package","max_iterations":1,"retry":{"initial_backoff_ms":100,"jitter_percent":20,"max_backoff_ms":60000,"multiplier":2},"type":"deterministic","verification":{}}],"version":"0.1.0"}