Papermatica

Litematica → Paper bridge with full NBT support.

Litematica's schematic paste tool normally can't carry block-entity data (chest, barrel, and hopper contents) or entity data across to a Paper server — when a Servux server isn't detected, Litematica falls back to spamming /setblock and /summon commands, neither of which can carry NBT, and which can flood the command/packet limits on a large paste.

Papermatica fixes this by implementing the real Servux network protocol (servux:litematics) server-side. Litematica already speaks this protocol natively — it just needs a server on the other end. With Papermatica installed, pasting a schematic places every block directly server-side, with its saved data restored exactly:

• Chests, barrels, hoppers, and other block entities paste with their full inventories intact.
• Entities (minecarts, item frames, armor stands, etc.) paste with their saved data and a fresh identity, so re-pasting the same schematic never collides with earlier copies.
• No commands, no packet-limit kicks — every block is written directly to the world.
• Redstone comes out settled, not mid-toggle: placement happens with all side effects suppressed, then a single clean update pass runs once the whole structure exists, followed by a pass that restores every block to exactly what the schematic saved (catching anything a block flipped while reacting to its now-real neighbors).
• No extra client-side mod required — players just need Litematica itself, no companion mod and no special build; see requirements below.

Requirements

• Server: plain, official Paper for Minecraft 1.21.11 — no fork or custom build needed, this is a normal plugin.
• Players who want to paste: a build of Litematica for 1.21.11 that has an "Entity Data Sync" option in its config (M → Configs → Generic). That option is the client half of the Servux protocol Papermatica speaks. Litematica's Servux support started out in a community fork (sakura-ryoko) rather than the original mod, but has since made it into the commonly distributed builds — if your Litematica shows that option, you're already good; if it doesn't, update Litematica.
• Players pasting must be op (or hold the papermatica.servux.paste permission) and in Creative mode, matching Litematica's own requirements for direct server-side pasting.

Installation

1. Download the plugin jar.
2. Drop the jar into your server's plugins/ folder and restart (or /reload confirm, though a full restart is recommended for a plugin doing network/world registration).
3. Check the console for:

   =================================
             Papermatica
      Litematica -> Paper Bridge
   =================================
   ...
   Servux bridge initialized (channel: servux:litematics)
   Papermatica enabled.
   

4. (Optional) Adjust permissions. Both nodes default to op; grant them explicitly through your permissions plugin if you want non-op players to paste:
   • papermatica.admin — the /papermatica diagnostics command.
   • papermatica.servux.paste — pasting schematics via Servux.

No plugin configuration file is needed for the core paste feature — it works as soon as the plugin is enabled and a player with the right permission connects with a compatible Litematica.

Client setup (for players)

This is the part that's easy to miss — Litematica does not attempt to detect a Servux server by default, even with Papermatica installed:

1. Make sure your Litematica has the "Entity Data Sync" option at all (see Requirements above — update Litematica if you don't see it).
2. Open Litematica's config (M → Configs → Generic) and enable "Entity Data Sync" (entityDataSync). This is off by default; without it, Litematica never sends the handshake that lets it discover Papermatica, and paste silently falls back to the broken /setblock command path.
3. Confirm "Paste Using Servux" (pasteUsingServux) is enabled — it defaults to on, so this is just a sanity check if pastes still don't seem to be using the direct path.
4. Join the server, load a schematic placement as usual, switch to Creative, and paste with the normal paste/execute-operation keybind. No new keybind or extra mod is needed.

Large schematics and client FPS

Pasting itself is server-side and effectively instant, but Litematica still renders a full ghost/hologram preview of a loaded schematic client-side, which can tank FPS on huge builds regardless of how fast the paste is. If that happens, bind a hotkey for "Toggle Schematic Rendering" (enableSchematicRendering) in Litematica's Hotkeys config, turn it off right before pasting a large schematic, and turn it back on afterward if you want the overlay back.

Known limitations

• A schematic containing a genuine redstone feedback loop (a clock, a torch/repeater oscillator) can still occasionally come out of paste in the wrong phase. This is an inherent property of how vanilla redstone evaluates updates in order, not something any schematic-paste tool (WorldEdit, Litematica+Servux, or Papermatica) can fully guarantee away tho there is a implementation to fix that issue.
• ReplaceMode and Litematica's paste layer-range restriction are accepted from the client but not yet applied — every paste currently places the full schematic.
• The "missing materials" comparison overlay (Litematica querying real in-world block/entity NBT to highlight differences) is not implemented — only the direct-paste path is.