docs

Author: EDToaster

evaluation.md docs/plans/2026-03-13-migration-eval.mdevaluation.md renamed to docs/plans/2026-03-13-migration-eval.md

@@ -1,4 +1,4 @@
-# LittleLogistics NeoForge 1.21.10 Migration Evaluation
+# LittleLogistics NeoForge 1.21.1 Migration Evaluation
 
 **Evaluator:** evaluator-migration
 **Date:** 2026-03-13
@@ -9,7 +9,7 @@
 
 ## Executive Summary
 
-After synthesizing discoveries from all 12 explorers, the migration from Forge 1.20.1 to NeoForge 1.21.10 is **technically demanding but tractable**. The mod has ~180 Java files, but only ~30 require non-trivial migration work. The adversarial explorer's core argument — that a focused big-bang port is faster than incremental abstraction — is correct and well-supported by the evidence.
+After synthesizing discoveries from all 12 explorers, the migration from Forge 1.20.1 to NeoForge 1.21.1 is **technically demanding but tractable**. The mod has ~180 Java files, but only ~30 require non-trivial migration work. The adversarial explorer's core argument — that a focused big-bang port is faster than incremental abstraction — is correct and well-supported by the evidence.
 
 The single most valuable pre-migration action is fixing a **pre-existing bug** found by the entity data explorer.
 

docs/plans/2026-03-13-migration.md

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+# NeoForge 1.21.1 Migration — Phase Plans
+
+Concrete, step-by-step migration plans for each phase of the Forge 1.20.1 → NeoForge 1.21.1 port.
+
+See [evaluation.md](../../../evaluation.md) for the comprehensive gap analysis that informed these plans.
+
+## Phases
+
+| Phase | Doc | Effort | Key Challenge |
+|-------|-----|--------|---------------|
+| 1 | [Build System](phase-1-build-system.md) | MEDIUM-HIGH | ForgeGradle → NeoGradle, Java 17 → 21 |
+| 1.5 | [Vanilla API Compatibility](phase-1.5-vanilla-api.md) | HIGH | Boat.Status physics rewrite, AttributeModifier, AbstractMinecart.Type removal |
+| 2 | [Mod Entrypoint & Registration](phase-2-registration.md) | MEDIUM | RegistryObject → DeferredHolder across 15 files |
+| 3 | [Networking](phase-3-networking.md) | MEDIUM | SimpleChannel → CustomPacketPayload records with StreamCodec |
+| 4 | [Capabilities](phase-4-capabilities.md) | CRITICAL | 14 getCapability() overrides, 15 LazyOptional fields, centralized RegisterCapabilitiesEvent |
+| 5 | [Entity Data & BlockEntity Serialization](phase-5-entity-data.md) | MEDIUM | defineSynchedData Builder pattern, HolderLookup.Provider on BlockEntity load/save |
+| 6 | [Data Components](phase-6-data-components.md) | HIGH | Codec design for TugRoute/LocoRoute, Item NBT → DataComponentType |
+| 7 | [Recipe & Data Generation](phase-7-recipe-datagen.md) | LOW-MEDIUM | RecipeOutput signature (NO Runner class in 1.21.1) |
+| 8 | [GUI / Screens](phase-8-gui-screens.md) | LOW-MEDIUM | NetworkHooks.openScreen() removal, RegisterMenuScreensEvent |
+| 9A | [Vanilla/NeoForge API Reworks](phase-9a-api-reworks.md) | MEDIUM | AbstractMinecart.Type physics rewrite, PartEntity relocation |
+| 9B | [Mechanical Cleanup](phase-9b-mechanical-cleanup.md) | LOW | 80x ResourceLocation find-and-replace |
+| 10 | [Create Mod Compatibility](phase-10-create-compat.md) | DEFERRED | Follow-up PR after Create for NeoForge 1.21.1 is available |
+
+## Execution Order
+
+Phases must be executed in order. Each phase gate requires `./gradlew build` to pass before proceeding to the next.
+
+```
+Phase 1 → 1.5 → 2 → 3 → 4 → 5 → 6 → 7 → 8 → 9A → 9B → 10
+```
+
+## Pre-Migration (Complete)
+
+The following pre-migration tasks were completed in run 561c8bb0:
+- Fixed defineId bug in FluidTankBargeEntity and FluidTankCarEntity
+- Removed dead EVENT_BUS.register(this) in ShippingMod
+- Replaced StallingCapability with instanceof pattern
+- Added JUnit 5 unit tests for SpringPhysicsUtil and route serialization