DAI 3.0 · STEP-BY-STEP

Multiplayer State, Checkpoints & Migrations

Build save-safe progression that survives death, updates and multiple players without cross-contamination.

Build from scratchTest in MinecraftMultiplayer-safe by designDAI 3.0

What you are building

Primary path: scoreboards/storage + migrate functions
Build save-safe progression that survives death, updates and multiple players without cross-contamination.

Step-by-step

  1. Separate global and per-player stateServer world milestones and player progression are different stores.
  2. Allocate ownershipPersonal ships/homes/instances need stable owner IDs and coordinates.
  3. Create physical checkpointsRecovery should use known-safe locations, not only phase numbers.
  4. Write idempotent migrationsEach version patch runs once and can safely detect already-correct worlds.
  5. Repair locallyPatch the affected room/shore/ship instead of rebuilding the entire world.
  6. Test two players at different stagesProgress, HUD and construction must remain independent.
  7. Test upgrade from an old save copyNever make the first migration test on the only save.

Definition of done

  • The feature still works after save/reload.
  • Server state is authoritative; presentation mirrors it.
  • Invalid input cannot duplicate rewards or bypass costs.
  • Two players can use the system without sharing unintended temporary state.
  • Any optional resource pack can be disabled without breaking datapack logic.

Next integration

Once this feature works alone, connect it to a complete loop instead of adding more isolated content. Use the complete-game tracks to see where it belongs in ACMS, Space Between Blocks, MineTrigger or Hollow Spiral.

← Tutorial HubCreate Anything →