Backstop | Exploit & Dupe Blocker v1.0.0

Backstop
Backstop blocks the exploit and dupe patterns that keep showing up on public servers: crash commands, oversized written books, broken anvil names, illegal item stacks, and drop-spam macros. Every catch gets logged. Owners keep full control over what runs and where.

Built for: Survival, SMP, public servers open to unknown players.

Five checks, on by default

• Crash commands - refuses known crash and lag commands (reload and its namespaced forms) plus absurdly long command strings.
• Book overflow - cancels written books padded with too many characters or pages, a common client-crash trick.
• Anvil overflow - clears anvil results with an oversized or formatting-stuffed name.
• Illegal stacks - caps items stacked past their natural max, a telltale dupe-glitch artifact.
• Rapid drop - blocks drop macros that spam items out far faster than a person can click.

Each check can run in log-only mode or actually block the action, per check.

See exactly what got caught

Every incident lands in a rolling log with the player, the check, and the detail, browsable in a paged GUI with /backstop log or filtered from chat with /backstop list, /backstop player, and /backstop type. Nothing to dig through server logs for.

Know what is active

/backstop checks shows every check, whether it is enabled, and whether it blocks or just logs, plus whether safe mode is on.

Players see a clean message, not a silent freeze

A blocked action gets a plain, configurable message instead of the client just hanging or an unexplained error.

Trial it safely
Safe mode logs and alerts on every detection without blocking anything, so owners can watch Backstop catch real activity on a live server before switching any check over to block.

Per-world and per-region control
Turn a check off in a specific world, like creative, or inside a named region such as a spawn arena, while it keeps running everywhere else. Every check runs everywhere by default until an owner says otherwise.

Discord alerts
Post every incident, or only the blocked ones, to a Discord channel webhook. No email, no third-party service, just the webhook URL an owner pastes in.

Features

• Five exploit and dupe checks, each independently configurable.
• Per-check switch between block and log-only.
• Safe mode: log and alert everything, block nothing, for safe trialing.
• Paged, filterable incident log GUI plus chat commands.
• Per-world and per-region check overrides.
• Discord webhook alerts with a configurable severity filter.
• Rolling in-memory log plus an optional incidents.log file.
• Config auto migration and an in-game reload.

Commands

• /backstop help - list the commands.
• /backstop log - open the incident log GUI.
• /backstop list [page] - list all incidents in chat.
• /backstop player <name> [page] - list incidents for one player.
• /backstop type <check> [page] - list incidents for one check.
• /backstop checks - show every check's state and safe mode.
• /backstop safemode [on|off] - toggle or set safe mode.
• /backstop clear - clear the incident log.
• /backstop reload - reload the config and messages.

Aliases: /bs, /exploitguard.

Permissions

• backstop.use - view the incident log and check list. Default: operators.
• backstop.admin - toggle safe mode, clear the log, and reload. Default: operators.

Requirements

• Minecraft 1.21 to 26.1.2.
• Paper, Spigot, or Bukkit.
• Java 21.

Installation

1. Drop Backstop-1.0.0.jar into your plugins folder.
2. Start the server once to generate the config.
3. Turn on safe mode first if you want to watch it catch real activity before it blocks anything, then edit config.yml to taste and run /backstop reload.

Try it first
Backstop is live on our test server, hosted here on BuiltByBit. Use the test server link on this page to connect and try the commands yourself.

Support
Questions and bug reports are welcome. Join the No Click Studios Discord at https://discord.gg/drBwA958bn.