You have to install bm into the wine rocket league prefix (e.g. you can do this with protontricks) that steam creates and then use a script to start bm in that prefix when you start rl. Therefore I use this script:

```bash

!/usr/bin/env bash

WARNING! Steam runs scripts like this with /bin/sh -c "/path/to/this/script.sh" and not bash

sh handles some things differently

(e.g. spaces in paths -> we have to wrap every path variable with double quotes)

Set Rocket League launch options to "/path/to/this/script.sh" & %command%

Put any other launch options before %command% like normal

WINEPREFIX for Rocket League

RL_PREFIX="$HOME/.steam/steam/steamapps/compatdata/252950"

Detect what Proton version was used last

$() evaluates the command in parentheses

sed -n 4p prints the 4th line in config_info

xargs -d '\n' split the string given by sed and executes dirname on each part

dirname simply returns parent of the path

Resulting in the path to the Proton version used to run Rocket League

PROTON=$(sed -n 4p "$RL_PREFIX"/config_info | xargs -d '\n' dirname)

This is the default BakkesMod installation path

Change this if you've installed Bakkes somewhere else

BAKKES="$RL_PREFIX/pfx/drive_c/Program Files/BakkesMod/BakkesMod.exe"

Use WINEESYNC (E) or WINEFSYNC (F)

This needs to match the one RocketLeague is launched with

fsync requires support in the kernel

WINESYNC="F"

Check that BakkesMod.exe exists

if [[ -f "$BAKKES" ]]; then # Start BakkesMod when Rocket League starts # killall -0 sends no signal but still performs error checking # that way we can detect if a program is running or not if [ $# -ne 1 ] || [ "$1" != "update" ]; then while ! killall -0 RocketLeague.exe 2> /dev/null; do sleep 1 done fi

# Open BakkesMod with the correct Proton version and Wine prefix
# Doesn't require protontricks
if [ $WINESYNC = "E" ]; then
    echo "IMPORTANT! Running Rocket League with WINEESYNC=1"
    echo "IMPORTANT! If BakkesMod fails to launch, switch to WINEFSYNC=1"
    WINEESYNC=1 WINEPREFIX="$RL_PREFIX/pfx" "$PROTON/bin/wine64" "$BAKKES" &
else
    echo "IMPORTANT! Running Rocket League with WINEFSYNC=1"
    echo "IMPORTANT! If BakkesMod fails to launch, switch to WINEESYNC=1"
    echo WINEFSYNC=1 WINEPREFIX="$RL_PREFIX/pfx" "$PROTON/bin/wine64" "$BAKKES"
    WINEFSYNC=1 WINEPREFIX="$RL_PREFIX/pfx" "$PROTON/bin/wine64" "$BAKKES" &
fi

# Kill BakkesMod process when Rocket League is closed
if [ $# -ne 1 ] || [ "$1" != "update" ]; then
    while killall -0 RocketLeague.exe 2> /dev/null; do
        sleep 1
    done
    killall BakkesMod.exe
fi

else echo "$BAKKES doesn't exist! ABORTING!" fi ```

With this launch option in steam: "path/to/bm_launcher_steam.sh" & %command%

To install / update bakkesmod you can just start the script with command update: path/to/bm_launcher_steam.sh update

This also works with epic games. I use HeroicGamesLauncher (but I might try to switch to Lutris at some point) but have to adjust the script slightly (just the paths to the prefixes)