Let old save files keep working after you change what a save contains

Every time you and the AI rename or reshape something the game saves, players with an older save lose their progress or start with a broken hero. This entry shows how to upgrade old saves one step at a time and how to refuse a save from a newer game.

Why this works

A save does not know which game wrote it unless it says so. Stamping a version number and changing it one small step at a time means any old save can reach the present shape by passing through every earlier step, and no old step ever needs rewriting.

When not to use it

Too much for a game with no saves, or one that only keeps a high score you can afford to lose. If the changes are so large that the old data means nothing any more, say so to the player and start fresh instead of forcing a conversion.

In the full entry

• What to build, step by step
• Starting values and the reason for each
• 3 common mistakes and the fix
• 28 lines of example code with 4 checks that pass
• How your AI shows you that it works

Say this to your AI

Use the Spielerando entry "Let old save files keep working after you change what a save contains" (read_entry action-save-version-upgrade) in my game. Build it step by step, and show me how you checked that it works.

Or skip this and connect the MCP: your AI then finds all of this by itself.Connect the MCP