Save Compatibility Lab

A save can deserialize without an exception and still lose a player's progress. Save Compatibility Lab models your current save types under Unity's real JsonUtility rules, compares them with the schema that shipped, and replays real old saves through today's code before release.

What it helps you do

• Declare save roots and shipped version numbers.
• Capture a committed schema snapshot of what players currently have.
• Detect renamed, removed, wrapped, newly unsupported, or silently dropped fields.
• Catch Unity serialization traps such as dictionaries, enum changes, deep nesting, and SerializeReference type changes.
• Keep a corpus of real or representative saves and replay it through current code.
• Validate each step in an explicit migration ladder.
• Export deterministic JSON, Markdown, and self-contained HTML reports and gate CI.

Use it before patches that touch player data, refactors of save models, serializer-version changes, or a long-lived game's next migration.

Version 1 targets Unity JsonUtility-compatible JSON. It does not model Json.NET, binary, or custom serializers, and it never rewrites saves, generates migrations, or edits code. A clean result covers the declared roots, snapshots, corpus, and migrations you supplied.

Read the complete documentation.