godot-save-load-systems

Use a SaveManager Autoload that writes a Dictionary to user:// via FileAccess, serialized as JSON or binary store_var. Include a version field, validate loaded data with data.get defaults, and save only at checkpoints or menus, never per physics frame.

JSON is human-readable and suits small to medium progress data, but loses type fidelity for Variants like Vector3. Binary store_var preserves types and handles larger blobs, but must use allow_objects=false for untrusted saves to avoid code execution risks.

Store a version field in every save and run a migration manager that upgrades the data one version hop at a time before loading. Never skip hops, and keep save schema versioning separate from engine version upgrades.

Setting allow_objects=true enables full object decoding, which allows arbitrary code execution from tampered or downloaded save files. Always use false for player saves, workshop mods, or any untrusted data, reserving true only for trusted local tooling.

Copy the existing save to a .bak file before overwriting, write to a temp file then rename, and optionally verify integrity with FileAccess.get_sha256. On mismatch, fall back to the backup instead of loading corrupted data.

Yes, use FileAccess.open_encrypted_with_pass to encrypt sensitive save slots with AES. The password must come from secure storage or a user secret, never hardcoded in the script, and encrypted saves should still use allow_objects=false.