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Working with mods and plugins

Mod platforms

By far the easiest way to work with mod and plugins, especially large numbers of them, is to utilize modpacks with one of the supported mod platforms.

The following are some supported mod platforms:

Download automation

On the left, there are sections describing some download automation options.

Mods vs Plugins

The terms "mods" and "plugins" can be quite confusing. Generally, the rule of thumb is that "mods" are used by the types that run client side to modify rendering, add new blocks, and add behaviors server, such as Forge and Fabric. "Plugins" are used by the types that only run on servers to add behaviors, commands, etc such as Paper (which derives from Bukkit/Spigot). There are also some types that are hybrids, such as Magma, that use both "mods" and "plugins"

Optional plugins, mods, and config attach points

There are optional volume paths that can be attached to supply content to be copied into the data area:

content in this directory is synchronized into /data/plugins for server types that use plugins, as described above. For special cases, the source can be changed by setting COPY_PLUGINS_SRC and destination by setting COPY_PLUGINS_DEST.
content in this directory is synchronized into /data/mods for server types that use mods, as described above. For special cases, the source can be changed by setting COPY_MODS_SRC and destination by setting COPY_MODS_DEST.
contents are synchronized into /data/config by default, but can be changed with COPY_CONFIG_DEST. For example, -v ./config:/config -e COPY_CONFIG_DEST=/data will allow you to copy over files like bukkit.yml and so on directly into the server directory. The source can be changed by setting COPY_CONFIG_SRC. Set SYNC_SKIP_NEWER_IN_DESTINATION=false if you want files from /config to take precedence over newer files in /data/config.

By default, the environment variable processing is performed on synchronized files that match the expected suffixes in REPLACE_ENV_SUFFIXES (by default "yml,yaml,txt,cfg,conf,properties,hjson,json,tml,toml") and are not excluded by REPLACE_ENV_VARIABLES_EXCLUDES and REPLACE_ENV_VARIABLES_EXCLUDE_PATHS. This processing can be disabled by setting REPLACE_ENV_DURING_SYNC to false.

If you want old mods/plugins to be removed before the content is brought over from those attach points, then add -e REMOVE_OLD_MODS=TRUE. You can fine tune the removal process by specifying the REMOVE_OLD_MODS_INCLUDE and REMOVE_OLD_MODS_EXCLUDE variables, which are comma separated lists of file glob patterns. If a directory is excluded, then it and all of its contents are excluded. By default, only jars are removed.

You can also specify the REMOVE_OLD_MODS_DEPTH (default is 16) variable to only delete files up to a certain level.

For example: -e REMOVE_OLD_MODS=TRUE -e REMOVE_OLD_MODS_INCLUDE="*.jar" -e REMOVE_OLD_MODS_DEPTH=1 will remove all old jar files that are directly inside the plugins/ or mods/ directory.

These paths work well if you want to have a common set of modules in a separate location, but still have multiple worlds with different server requirements in either persistent volumes or a downloadable archive.

For more flexibility with mods/plugins preparation, you can declare other directories, files, and URLs to use in the MODS / PLUGINS variables.

Zip file modpack

Like the WORLD option above, you can specify the URL or container path of a "mod pack" to download and install into mods for Forge/Fabric or plugins for Bukkit/Spigot. To use this option pass the environment variable MODPACK, such as

docker run -d -e MODPACK= ...


The referenced URL/file must be a zip file with one or more jar files at the top level of the zip archive. Make sure the jars are compatible with the particular TYPE of server you are running.

Generic pack files

To install all the server content (jars, mods, plugins, configs, etc.) from a zip or tgz file, then set GENERIC_PACK to the container path or URL of the archive file. This can also be used to apply a CurseForge modpack that is missing a server start script and/or Forge installer.

If multiple generic packs need to be applied together, set GENERIC_PACKS instead, with a comma separated list of archive file paths and/or URLs to files.

To avoid repetition, each entry will be prefixed by the value of GENERIC_PACKS_PREFIX and suffixed by the value of GENERIC_PACKS_SUFFIX, both of which are optional. For example, the following variables


would expand to,

If applying large generic packs, the update can be time-consuming. To skip the update set SKIP_GENERIC_PACK_UPDATE_CHECK to "true". Conversely, the generic pack(s) can be forced to be applied by setting FORCE_GENERIC_PACK_UPDATE to "true".

The most time-consuming portion of the generic pack update is generating and comparing the SHA1 checksum. To skip the checksum generation, set SKIP_GENERIC_PACK_CHECKSUM to "true".

Mods/plugins list

You may also download or copy over individual mods/plugins using the MODS or PLUGINS environment variables. Both are a comma or newline delimited list of - URL of a jar file - container path to a jar file - container path to a directory containing jar files

docker run -d -e MODS=,/plugins/common,/plugins/special/mod2.jar ...

The newline delimiting allows for compose file usage like:

      PLUGINS: |

Mod/Plugin URL Listing File

As an alternative to MODS/PLUGINS, the variable MODS_FILE or PLUGINS_FILE can be set with the container path or URL of a text file listing a mod/plugin URLs on each line. For example, the following

 -e MODS_FILE=/extras/mods.txt

would load from a file mounted into the container at /extras/mods.txt. That file might look like:
# This and next line are ignored


Blank lines and lines that start with a # will be ignored

This compose file shows another example of using this feature.

Remove old mods/plugins

When the MODPACK option above is specified you can also instruct script to delete old mods/plugins prior to installing new ones. This behaviour is desirable in case you want to upgrade mods/plugins from downloaded zip file.

To use this option pass the environment variable REMOVE_OLD_MODS=TRUE, such as

docker run -d -e REMOVE_OLD_MODS=TRUE -e MODPACK= ...


All content of the mods or plugins directory will be deleted before unpacking new content from the MODPACK or MODS.