diff --git a/.github/scripts/validate-unity-distribution.py b/.github/scripts/validate-unity-distribution.py
index ea116b56..9391ea67 100644
--- a/.github/scripts/validate-unity-distribution.py
+++ b/.github/scripts/validate-unity-distribution.py
@@ -2,6 +2,7 @@
 
 import json
 import re
+import subprocess
 import sys
 from pathlib import Path
 
@@ -10,6 +11,11 @@
 DEMO = ROOT / "examples/demo"
 BOOTSTRAP = ROOT / "examples/demo/Assets/OneSignal"
 SAMPLE = ROOT / "com.onesignal.unity.core/Samples~"
+PACKAGES = (
+    "com.onesignal.unity.android",
+    "com.onesignal.unity.core",
+    "com.onesignal.unity.ios",
+)
 INVENTORY = BOOTSTRAP / "Editor/Resources/OneSignalFileInventory.asset"
 
 EXCLUDED_PREFIXES = (
@@ -64,6 +70,52 @@ def validate_inventory() -> None:
         )
 
 
+def is_unity_hidden(part: str) -> bool:
+    return part.startswith(".") or part.endswith("~")
+
+
+def packed_files(package: str) -> list[str]:
+    output = subprocess.run(
+        ["npm", "pack", "--dry-run", "--json", "--ignore-scripts"],
+        cwd=ROOT / package,
+        check=True,
+        capture_output=True,
+        text=True,
+    ).stdout
+    return [entry["path"] for entry in json.loads(output)[0]["files"]]
+
+
+def validate_package_metas() -> None:
+    # UPM packages are immutable, so Unity ignores any asset that ships without a valid .meta.
+    guids: dict[str, str] = {}
+    for package in PACKAGES:
+        packed = set(packed_files(package))
+
+        assets = set()
+        for path in packed:
+            if path.endswith(".meta"):
+                continue
+            parts = path.split("/")
+            if any(is_unity_hidden(part) for part in parts):
+                continue
+            assets.add(path)
+            assets.update("/".join(parts[:i]) for i in range(1, len(parts)))
+
+        missing = sorted(f"{package}/{asset}.meta" for asset in assets if f"{asset}.meta" not in packed)
+        if missing:
+            fail(f"packed assets are missing .meta files: {', '.join(missing)}")
+
+        for meta in sorted(f"{asset}.meta" for asset in assets):
+            path = f"{package}/{meta}"
+            match = re.search(r"^guid:\s*([0-9a-f]{32})\s*$", (ROOT / path).read_text(), re.MULTILINE)
+            if match is None:
+                fail(f"{path} has no valid guid")
+            guid = match.group(1)
+            if guid in guids:
+                fail(f"{path} reuses guid {guid} from {guids[guid]}")
+            guids[guid] = path
+
+
 def validate_sample() -> None:
     for filename, expected_guid in REQUIRED_SAMPLE_GUIDS.items():
         path = SAMPLE / filename
@@ -111,6 +163,7 @@ def main() -> None:
     if not (BOOTSTRAP / "Documentation").is_dir():
         fail("exportable bootstrap documentation is missing")
     validate_inventory()
+    validate_package_metas()
     validate_sample()
     print("Unity distribution layout is valid.")
 
diff --git a/.github/workflows/cd.yml b/.github/workflows/cd.yml
index 88c8e4be..fd59028d 100644
--- a/.github/workflows/cd.yml
+++ b/.github/workflows/cd.yml
@@ -53,6 +53,9 @@ jobs:
         run: |
           echo "Tag from output: [${{ steps.npm-tag.outputs.tag }}]"
 
+      - name: Validate Unity distribution layout
+        run: python3 .github/scripts/validate-unity-distribution.py
+
       - name: Publish packages
         run: |
           publish_pkg() {
diff --git a/com.onesignal.unity.core/Runtime/InputGuard.cs.meta b/com.onesignal.unity.core/Runtime/InputGuard.cs.meta
new file mode 100644
index 00000000..3a4ebad9
--- /dev/null
+++ b/com.onesignal.unity.core/Runtime/InputGuard.cs.meta
@@ -0,0 +1,2 @@
+fileFormatVersion: 2
+guid: d0c2ff6a1f8ce4971a952d24320ac599
\ No newline at end of file