Lobby Manager

A server-side Fabric mod for Minecraft 26.3 that sends players to a protected lobby when they join, allows them to return to survival, and keeps the lobby and survival inventories separate. Designed for servers using Worlds (Multiverse for Fabric) and optionally Easy NPC.

Beta source release — build and test before production use. This repository contains source code, not a verified server-ready JAR. Back up your world and player data before installing or upgrading. Inventory-related mods may be incompatible.

• Lobby on join: players are sent to the custom /setlobby location in the lobby dimension when connecting (or the lobby world spawn until /setlobby is configured).
• Independent spawns: /setlobby sets the login/lobby teleport point without changing /setworldspawn in the Overworld.
• Overworld respawn after death: when respawnAtOverworldSpawn is enabled, death sends players to the Overworld world spawn set with /setworldspawn, never to the lobby; this overrides beds and respawn anchors.
• Return to survival: players can return to their last saved survival position, including a position in the Nether, End, or another loaded dimension. Players without a saved position use the default survival world spawn.
• Separate inventories: saves main inventory, armor/equipment/offhand, Ender Chest, XP, hunger, health, and game mode independently for lobby and survival. Survival dimensions share one inventory group.
• Lobby protection: enables Adventure Mode for visitors and blocks typical block breaking, block interaction, item use, entity attacks, entity interaction (except for tagged NPCs), damage, dropped items, and pickups. Hunger is kept full.
• Admin build mode: an operator can temporarily switch between Creative and Adventure Mode inside the lobby.
• Custom command messages: edit all player-facing command feedback in a JSON configuration file. Messages are English by default, but can be changed to any language.
• Automatic saves: stores player records periodically, on dimension group changes, and on disconnect.

These are top-level commands; there is no required subcommand prefix. If another installed mod provides one of the same commands, it may conflict.

• Minecraft 26.3
• Fabric Loader 0.19.5 or newer compatible release
• Fabric API 0.162.0+26.3
• Java 25
• Worlds (Multiverse for Fabric) for creating and loading the lobby world
• Easy NPC is optional for click-to-survival NPCs

The Fabric metadata suggests Worlds, rather than requiring a particular Worlds mod ID; configure and load the lobby dimension before players join.

1. Back up your entire server, including inventory data, world saves, and old mod config data. Test on a copy.

2. Install the built Lobby Manager JAR plus the required Fabric components in the server's mods/ folder.

3. Create a lobby world using Worlds (if one does not exist):

   /worlds create lobby
   /worlds tp lobby

    

4. In the lobby dimension, set it to load at server startup:

   /worlds settings loadOnStartup true

    

5. In the lobby world, apply the recommended lobby gamerules below. Commands may depend on your Worlds/Minecraft versions.

6. Start/restart the server. The mod creates config/lobbymanager.json on first launch. Check that lobbyDimension matches the actual world ID, normally minecraft:lobby, and restart if you change it.

7. In the lobby world, stand exactly where players should arrive and run:

   /setlobby

    

   Your precise coordinates and facing direction are written to config/lobbymanager.json immediately. This does not change the vanilla world spawn.

8. Go to the Overworld and set the death-respawn point independently:

   /setworldspawn

    

   With respawnAtOverworldSpawn: true, deaths always respawn at the Overworld world spawn, including players who die in another dimension. Beds and respawn anchors are ignored for death respawns. The optional /returntosurvival NPC still returns players to their previous survival location, except that after dying the saved return location is updated to the Overworld spawn.

9. Join with a test player, confirm joining goes to /setlobby, dying in survival respawns at /setworldspawn, and returning from the NPC works with the correct inventory.

Run these while inside the lobby world, not in survival:

/gamerule spawn_mobs false
/gamerule spawn_monsters false
/gamerule pvp false
/gamerule keep_inventory true
/gamerule fire_spread_radius_around_player 0
/gamerule tnt_explodes false

Worlds supports world-specific gamerules. Important: noMobSpawning in the config is only a placeholder setting in this version; the mod does not automatically enforce mob spawn blocking. Use lobby-specific gamerules to do so. Modded spawners and administrative commands may behave differently.

An NPC is optional. Players can always use /returntosurvival directly; the NPC is simply a clickable shortcut.

1. Install an Easy NPC version compatible with your Minecraft/Fabric setup and create a Survival NPC inside the lobby.

2. The lobby blocks normal entity interactions. To make your NPC clickable, assign it the configured scoreboard tag. Stand close to the NPC and run:

   /tag @e[sort=nearest,limit=1,type=!minecraft:player] add lobbymanager_npc

    

   Double-check the selected entity. A more specific type= filter is safer when you know the NPC entity type. The string lobbymanager_npc must match the allowedNpcTag setting in config/lobbymanager.json.

3. In the NPC's Actions settings, attach the command returntosurvival (or /returntosurvival if the field requires a slash) to the click action or an NPC dialogue button.

4. Configure the command to run as the player clicking the NPC. If run as the NPC or the console, the command will not have the correct player context.

5. Test by clicking the NPC as a non-operator player. Confirm that the player returns to survival with the correct inventory.

If an NPC still cannot be clicked, verify its scoreboard tag, interaction settings, and compatibility with Easy NPC. Other mods may handle NPC clicks differently.

Edit config/lobbymanager.json while the server is stopped, then restart the server. The full set of editable messages is included in config-example.json.

For example:

{
  "lobbyDimension": "minecraft:lobby",
  "respawnAtOverworldSpawn": true,
  "messages": {
    "prefix": "[Lobby Manager] ",
    "lobbySuccess": "Welcome to the lobby!",
    "setLobbySuccess": "Lobby position saved at {x}, {y}, {z}.",
    "buildModeEnabled": "You can now build in the lobby.",
    "buildModeDisabled": "Build mode is off.",
    "survivalSuccess": "Have fun in survival!"
  }
}

This is an excerpt, not a replacement for the entire config. Existing settings can remain unchanged. All default messages are in English; you may translate any value. To hide an individual notification, set its message text to "". Change messages.prefix to adjust the tag printed before notifications, or set it to "" for no prefix. The {dimension} placeholder in lobbyWorldUnavailable is replaced by the configured lobby world ID. The {x}, {y}, and {z} placeholders in setLobbySuccess display the saved lobby spawn coordinates. Message settings take effect after a restart, not immediately.

The lobbySpawn position is managed by the /setlobby command; you do not need to edit its coordinates manually. It is stored in the same JSON file and survives server restarts. When lobbySpawn is absent or null, /lobby and automatic joins fall back to the lobby world's own spawn. respawnAtOverworldSpawn defaults to true; set it to false to restore vanilla death respawn behavior, including beds and respawn anchors. Changes to this Boolean setting require a restart. Neither /setlobby nor /lobby changes the Overworld spawn, and changing /setworldspawn does not move the lobby spawn.

Other settings include lobbyOnJoin, lobbyAdventure, noBlockBreak, noBlockPlaceOrUse, noPlayerAttacks, noDamage, noHunger, noItemPickup, noItemDrop, separateInventories, backupIntervalTicks, and joinDelayTicks.

• Configuration: config/lobbymanager.json
• Player records: config/lobbymanager/players/<uuid>.json
• NPC tag by default: lobbymanager_npc

Upgrading from an earlier version: The mod ID, config path, Java package, and player save directory have changed. Do not delete previous player records. With the server offline, copy your existing player JSON files from the previous version's player-save directory to config/lobbymanager/players/ and recreate the new settings in config/lobbymanager.json. Keep a full backup and verify inventory restoration on a test server first. Renaming the code package alone does not migrate data.

This project includes a GitHub Actions workflow and Gradle build files. A Gradle wrapper is not included.

• Use Java 25 and a Gradle version compatible with the configured Fabric Loom plugin (the workflow currently uses Gradle 9.7.0).

• From the project folder, run:

  gradle clean build

   

• After a successful build, find build/libs/lobby-manager-0.4.0-beta.jar. Use this main JAR in the server's mods/ folder (not the -sources.jar).

• Alternatively, push the source to GitHub, select Actions, and run the Build Fabric 26.3 mod workflow. Download its JAR artifact after a successful build.

A successful compile and in-game test are still required. Dependencies and API methods may need updating if Minecraft/Fabric changes.

• Always test first on a backup server, particularly after changing mod IDs or upgrading an existing world.
• An unexpected crash during inventory switching may desynchronize saved snapshots and Minecraft's player.dat; automated saves are not a replacement for server backups.
• Other mods may bypass lobby protection callbacks or interfere with custom inventory management.
• When respawnAtOverworldSpawn is enabled, the mod explicitly sends dead players to the Overworld spawn; configured beds and respawn anchors will not be used. When disabled, standard Minecraft respawn rules apply.
• If the server does not have a loaded Overworld, the mod logs an error and lets the vanilla respawn location stand.
• NPC compatibility depends on the installed Easy NPC release and its command execution context.
• noMobSpawning is currently not enforced by Java code; use world-specific gamerules.