diff --git a/.github/workflows/modrinth-publish.yml b/.github/workflows/modrinth-publish.yml
new file mode 100644
index 0000000..383d672
--- /dev/null
+++ b/.github/workflows/modrinth-publish.yml
@@ -0,0 +1,65 @@
+name: Publish to Modrinth
+
+on:
+  release:
+    types: [published]
+  workflow_dispatch:
+    inputs:
+      tag:
+        description: 'Release tag to publish (e.g. 1.17.1)'
+        required: true
+        type: string
+      changelog:
+        description: 'Changelog / release notes (markdown)'
+        required: false
+        type: string
+
+jobs:
+  publish:
+    runs-on: ubuntu-latest
+    permissions:
+      contents: read
+
+    steps:
+      - name: Checkout repository
+        uses: actions/checkout@v4
+
+      - name: Set up Java 21
+        uses: actions/setup-java@v4
+        with:
+          java-version: '21'
+          distribution: 'temurin'
+
+      - name: Cache Maven packages
+        uses: actions/cache@v4
+        with:
+          path: ~/.m2
+          key: ${{ runner.os }}-m2-${{ hashFiles('**/pom.xml') }}
+          restore-keys: ${{ runner.os }}-m2
+
+      - name: Build with Maven
+        run: mvn -B package --no-transfer-progress
+        env:
+          GIT_BRANCH: origin/master
+
+      - name: Publish to Modrinth
+        uses: cloudnode-pro/modrinth-publish@v2
+        with:
+          token: ${{ secrets.MODRINTH_TOKEN }}
+          project: ${{ secrets.MODRINTH_PROJECT_ID }}
+          version: ${{ github.event.release.tag_name || inputs.tag }}
+          changelog: ${{ github.event.release.body || inputs.changelog }}
+          loaders: |-
+            paper
+            purpur
+          game-versions: |-
+            1.21.5
+            1.21.6
+            1.21.7
+            1.21.8
+            1.21.9
+            1.21.10
+            1.21.11
+            26.1
+            26.1.1
+          files: target/InvSwitcher-${{ github.event.release.tag_name || inputs.tag }}.jar
diff --git a/CLAUDE.md b/CLAUDE.md
index 54725bf..a0d81d7 100644
--- a/CLAUDE.md
+++ b/CLAUDE.md
@@ -9,11 +9,15 @@ InvSwitcher is a BentoBox addon for Minecraft (Spigot/Bukkit) that gives players
 ## Build Commands
 
 - **Build**: `mvn clean package`
-- **Run tests**: `mvn test -Dmaven.compiler.forceJavacCompilerUse=true`
-- **Run a single test class**: `mvn test -Dmaven.compiler.forceJavacCompilerUse=true -Dtest=StoreTest`
-- **Run a single test method**: `mvn test -Dmaven.compiler.forceJavacCompilerUse=true -Dtest=StoreTest#testMethodName`
+- **Run tests**: `mvn test`
+- **Run a single test class**: `mvn test -Dtest=StoreTest`
+- **Run a single test method**: `mvn test -Dtest=StoreTest#testMethodName`
 
-Requires Java 21. The build produces a shaded JAR in `target/`. The `-Dmaven.compiler.forceJavacCompilerUse=true` flag is needed to work around a compiler hashing bug with the current JDK.
+Requires Java 21. The build produces a shaded JAR in `target/`.
+
+## CI
+
+Jenkins at ci.codemc.io builds the `develop` and `master` branches. The CI agent runs JDK 25 (OpenJDK_25) targeting release 21. The `maven-compiler-plugin` has `forceJavacCompilerUse=true` set in the pom.xml to work around a JDK compiler hashing bug (`"this.hashes" is null`) that surfaces when compiling on JDK 25+. Do not remove this flag.
 
 ## Architecture
 
@@ -33,3 +37,92 @@ This is a BentoBox Addon (extends `Addon`, not a standalone Bukkit plugin). Key
 - **Backward compatibility migration**: `Store.getInventory()` migrates world-only data to island-specific keys on first load if no island-specific data exists yet.
 - Statistics saving runs asynchronously via `Bukkit.getScheduler()` except during shutdown (where scheduling is unavailable).
 - Tests use JUnit 5 + MockBukkit + Mockito. The surefire plugin requires extensive `--add-opens` flags (already configured in pom.xml).
+
+## Dependency Source Lookup
+
+When you need to inspect source code for a dependency (e.g., BentoBox, addons):
+
+1. **Check local Maven repo first**: `~/.m2/repository/` — sources jars are named `*-sources.jar`
+2. **Check the workspace**: Look for sibling directories or Git submodules that may contain the dependency as a local project (e.g., `../bentoBox`, `../addon-*`)
+3. **Check Maven local cache for already-extracted sources** before downloading anything
+4. Only download a jar or fetch from the internet if the above steps yield nothing useful
+
+Prefer reading `.java` source files directly from a local Git clone over decompiling or extracting a jar.
+
+In general, the latest version of BentoBox should be targeted.
+
+## Project Layout
+
+Related projects are checked out as siblings under `~/git/`:
+
+**Core:**
+- `bentobox/` — core BentoBox framework
+
+**Game modes:**
+- `addon-acidisland/` — AcidIsland game mode
+- `addon-bskyblock/` — BSkyBlock game mode
+- `Boxed/` — Boxed game mode (expandable box area)
+- `CaveBlock/` — CaveBlock game mode
+- `OneBlock/` — AOneBlock game mode
+- `SkyGrid/` — SkyGrid game mode
+- `RaftMode/` — Raft survival game mode
+- `StrangerRealms/` — StrangerRealms game mode
+- `Brix/` — plot game mode
+- `parkour/` — Parkour game mode
+- `poseidon/` — Poseidon game mode
+- `gg/` — gg game mode
+
+**Addons:**
+- `addon-level/` — island level calculation
+- `addon-challenges/` — challenges system
+- `addon-welcomewarpsigns/` — warp signs
+- `addon-limits/` — block/entity limits
+- `addon-invSwitcher/` / `invSwitcher/` — inventory switcher
+- `addon-biomes/` / `Biomes/` — biomes management
+- `Bank/` — island bank
+- `Border/` — world border for islands
+- `Chat/` — island chat
+- `CheckMeOut/` — island submission/voting
+- `ControlPanel/` — game mode control panel
+- `Converter/` — ASkyBlock to BSkyBlock converter
+- `DimensionalTrees/` — dimension-specific trees
+- `discordwebhook/` — Discord integration
+- `Downloads/` — BentoBox downloads site
+- `DragonFights/` — per-island ender dragon fights
+- `ExtraMobs/` — additional mob spawning rules
+- `FarmersDance/` — twerking crop growth
+- `GravityFlux/` — gravity addon
+- `Greenhouses-addon/` — greenhouse biomes
+- `IslandFly/` — island flight permission
+- `IslandRankup/` — island rankup system
+- `Likes/` — island likes/dislikes
+- `Limits/` — block/entity limits
+- `lost-sheep/` — lost sheep adventure
+- `MagicCobblestoneGenerator/` — custom cobblestone generator
+- `PortalStart/` — portal-based island start
+- `pp/` — pp addon
+- `Regionerator/` — region management
+- `Residence/` — residence addon
+- `TopBlock/` — top ten for OneBlock
+- `TwerkingForTrees/` — twerking tree growth
+- `Upgrades/` — island upgrades (Vault)
+- `Visit/` — island visiting
+- `weblink/` — web link addon
+- `CrowdBound/` — CrowdBound addon
+
+**Data packs:**
+- `BoxedDataPack/` — advancement datapack for Boxed
+
+**Documentation & tools:**
+- `docs/` — main documentation site
+- `docs-chinese/` — Chinese documentation
+- `docs-french/` — French documentation
+- `BentoBoxWorld.github.io/` — GitHub Pages site
+- `website/` — website
+- `translation-tool/` — translation tool
+
+Check these for source before any network fetch.
+
+## Key Dependencies (source locations)
+
+- `world.bentobox:bentobox` → `~/git/bentobox/src/`