ViaBackwards

ViaBackwards

Allow older Java Edition clients to connect to newer servers.

by
1.7M Downloads
bungeecordfabricfoliapaperspongevelocityutility
Rent Server with this Mod

About this Mod

ViaBackwards

On Fabric, use either ViaFabric or ViaFabricPlus. To override the included version

  • in ViaFabric, put ViaBackwards into the mods folder
  • in ViaFabricPlus, put ViaBackwards into the ViaFabricPlus/jars folder

Depending on the platform and version, this also requires ViaVersion.

Requires Java 17. See here how to update your installed Java version. As a last resort, you can download Java 8 downgraded builds from our ci.

Get access to Via* with new MC version support early

Starting with 1.20.5, ViaVersion and ViaBackwards will only be released a day or so after a Minecraft update unless the protocol changes of the update were trivial. If you want early-access, usually days or even weeks before the final release, you can subscribe to either:

  • GitHub Sponsors (preferred option, also comes with source code access. Use the /verify command on this Discord after), or alternatively
  • Patreon (see the highest tier and make sure to link Patreon to your Discord account under Discord Settings->Connections)

Note on release channels

It is recommended to always use the latest beta release. Alpha builds are used for work on snapshot version compatibility or other cutting-edge changes.

Always use the same build channel across the ViaVersion, ViaBackwards, and ViaRewind projects.

Releases/Dev Builds

You can find releases in the following places:

Dev builds for all of our projects are on our Jenkins server:

Known issues

  • 1.17+ min_y and height world values that are not 0/256 are not supported. Clients older than
    1.17 will not be able to see or interact with blocks below y=0 and above y=255
  • <1.17 clients on 1.17+ servers might experience inventory desyncs on certain inventory click actions
  • Sound mappings are incomplete (see here)

Other Links

Maven: https://repo.viaversion.com

List of contributors: https://github.com/ViaVersion/ViaBackwards/graphs/contributors

Special Thanks

https://www.yourkit.com/

YourKit supports open source projects with innovative and intelligent tools
for monitoring and profiling Java and .NET applications.
YourKit is the creator of YourKit Java Profiler,
YourKit .NET Profiler,
and YourKit YouMonitor.

Available Versions

5.11.0release
MC 1.10, 1.10.1, 1.10.2, 1.11, 1.11.1, 1.11.2, 1.12, 1.12.1, 1.12.2, 1.13, 1.13.1, 1.13.2, 1.14, 1.14.1, 1.14.2, 1.14.3, 1.14.4, 1.15, 1.15.1, 1.15.2, 1.16, 1.16.1, 1.16.2, 1.16.3, 1.16.4, 1.16.5, 1.17, 1.17.1, 1.18, 1.18.1, 1.18.2, 1.19, 1.19.1, 1.19.2, 1.19.3, 1.19.4, 1.20, 1.20.1, 1.20.2, 1.20.3, 1.20.4, 1.20.5, 1.20.6, 1.21, 1.21.1, 1.21.2, 1.21.3, 1.21.4, 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, 26.1.2, 26.2fabric, folia, paper, velocity
July 12, 2026
5.10.0release
MC 1.10, 1.10.1, 1.10.2, 1.11, 1.11.1, 1.11.2, 1.12, 1.12.1, 1.12.2, 1.13, 1.13.1, 1.13.2, 1.14, 1.14.1, 1.14.2, 1.14.3, 1.14.4, 1.15, 1.15.1, 1.15.2, 1.16, 1.16.1, 1.16.2, 1.16.3, 1.16.4, 1.16.5, 1.17, 1.17.1, 1.18, 1.18.1, 1.18.2, 1.19, 1.19.1, 1.19.2, 1.19.3, 1.19.4, 1.20, 1.20.1, 1.20.2, 1.20.3, 1.20.4, 1.20.5, 1.20.6, 1.21, 1.21.1, 1.21.2, 1.21.3, 1.21.4, 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, 26.1.2, 26.2fabric, folia, paper, velocity
June 19, 2026
5.9.1release
MC 1.10, 1.10.1, 1.10.2, 1.11, 1.11.1, 1.11.2, 1.12, 1.12.1, 1.12.2, 1.13, 1.13.1, 1.13.2, 1.14, 1.14.1, 1.14.2, 1.14.3, 1.14.4, 1.15, 1.15.1, 1.15.2, 1.16, 1.16.1, 1.16.2, 1.16.3, 1.16.4, 1.16.5, 1.17, 1.17.1, 1.18, 1.18.1, 1.18.2, 1.19, 1.19.1, 1.19.2, 1.19.3, 1.19.4, 1.20, 1.20.1, 1.20.2, 1.20.3, 1.20.4, 1.20.5, 1.20.6, 1.21, 1.21.1, 1.21.2, 1.21.3, 1.21.4, 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, 26.1.2fabric, folia, paper, velocity
May 4, 2026
5.9.0release
MC 1.10, 1.10.1, 1.10.2, 1.11, 1.11.1, 1.11.2, 1.12, 1.12.1, 1.12.2, 1.13, 1.13.1, 1.13.2, 1.14, 1.14.1, 1.14.2, 1.14.3, 1.14.4, 1.15, 1.15.1, 1.15.2, 1.16, 1.16.1, 1.16.2, 1.16.3, 1.16.4, 1.16.5, 1.17, 1.17.1, 1.18, 1.18.1, 1.18.2, 1.19, 1.19.1, 1.19.2, 1.19.3, 1.19.4, 1.20, 1.20.1, 1.20.2, 1.20.3, 1.20.4, 1.20.5, 1.20.6, 1.21, 1.21.1, 1.21.2, 1.21.3, 1.21.4, 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, 26.1.2fabric, folia, paper, velocity
April 19, 2026
5.8.1release
MC 1.10, 1.10.1, 1.10.2, 1.11, 1.11.1, 1.11.2, 1.12, 1.12.1, 1.12.2, 1.13, 1.13.1, 1.13.2, 1.14, 1.14.1, 1.14.2, 1.14.3, 1.14.4, 1.15, 1.15.1, 1.15.2, 1.16, 1.16.1, 1.16.2, 1.16.3, 1.16.4, 1.16.5, 1.17, 1.17.1, 1.18, 1.18.1, 1.18.2, 1.19, 1.19.1, 1.19.2, 1.19.3, 1.19.4, 1.20, 1.20.1, 1.20.2, 1.20.3, 1.20.4, 1.20.5, 1.20.6, 1.21, 1.21.1, 1.21.2, 1.21.3, 1.21.4, 1.21.5, 1.21.6, 1.21.7, 1.21.8, 1.21.9, 1.21.10, 1.21.11, 26.1fabric, folia, paper, velocity
March 30, 2026

How to Install ViaBackwards on Your Server

1

Order Server

Order a Minecraft Java server with at least 3 GB RAM (4 GB recommended).

2

Set bungeecord Loader

In the panel under "Egg", select the bungeecord loader and matching Minecraft version (26.2).

3

Install Mod

Open the mod browser in the dashboard and search for "ViaBackwards". Click "Install" – done! Alternatively, upload the .jar via SFTP to the /mods folder.

Compatibility

Mod Loaders

bungeecordfabricfoliapaperspongevelocity

Minecraft Versions

26.2, 26.1.2, 26.1.1 (+56 more)

Server-side

~ Optional

Recommended RAM

4 GB(min. 3 GB)

Frequently Asked Questions

ViaBackwards server crashes on startup – what to do?

Most common cause: wrong bungeecord version or insufficient RAM. Check the server log (latest.log) for "OutOfMemoryError" or "Mixin" errors. With Mado Hosting: ensure at least 3 GB RAM is allocated and the loader matches the mod version (26.2). You can switch loaders with one click in the panel.

Is ViaBackwards compatible with bungeecord and fabric and folia and paper and sponge and velocity?

ViaBackwards officially supports bungeecord, fabric, folia, paper, sponge, velocity for Minecraft 26.2, 26.1.2, 26.1.1. The Mado dashboard automatically detects incompatible loader combinations.

Server lagging with ViaBackwards – how to optimize performance?

Recommended RAM: 4 GB (per 8 players). Use /spark profiler to check if ViaBackwards consumes the most tick time. Common fixes: reduce server view-distance to 8-10, install "performant" or "starlight" as supplementary mods on Forge. With Mado Hosting, your server runs on NVMe SSDs with dedicated CPU cores for minimal latency.

Rent Modded Server

Install ViaBackwards with just one click on your server.

Recommended RAM
4 GBfrom €5.2/mo
Minimum 3 GB | per 8 players
Create Server Now
1-Click Mod Install
NVMe SSD Storage
DDoS Protection included

Details

License
GNU General Public License v3.0 only
Server-side
Optional

Supported Versions

26.226.1.226.1.126.11.21.111.21.101.21.91.21.81.21.71.21.6+49 more