Compile RetroArch using DietPi v9.12.1 on Raspberry Pi Zero W. Use a microSD of at the very least 8GB. https://github.com/libretro/RetroArch/issues/7606#issuecomment-2825605112

compile-retroarch-raspi0w.sh

#!/bin/bash
# Compile RetroArch using DietPi v9.12.1 on Raspberry Pi Zero W.
# Use a microSD of at the very least 8GB.
#
# Workflow
#  1. Enable strict error handling (errexit, nounset, pipefail).
#  2. Declare readonly variables for RetroArch user, home directory, and groups.
#  3. Create `retro` user (with home directory and locked password) if it doesn't exist.
#  4. Define and install all required build dependencies via apt.
#  5. Clone RetroArch repository at the specified tag if not already present, and measure clone time.
#  6. Change ownership of RetroArch source directory to `retro` user.
#  7. As `retro` user, configure and compile RetroArch as `retro` user, then record build end time.
#  8. Calculate apt, clone, build, and total durations and output a formatted build summary.
#
# https://gist.github.com/theAkito/cb23060ff70e235406caf810246d1c1d
#
# https://github.com/libretro/RetroArch/issues/7606
# https://docs.libretro.com/guides/rpi/

# Strict Mode
set -o errexit
set -o nounset
set -o pipefail

declare -r RETRO_USER="retro"
declare -r RETRO_HOME_DIR="/home/${RETRO_USER}"
declare -r RETRO_GROUPS="audio,video"

# Create retro user
function useradd_retro {
  if ! id "${RETRO_USER}" &>/dev/null; then
    useradd \
      --create-home \
      --home-dir "${RETRO_HOME_DIR}" \
      --shell /bin/bash \
      --groups "${RETRO_GROUPS}" \
      "${RETRO_USER}"
    passwd -l "${RETRO_USER}"
  fi
}
useradd_retro

declare -r DEPS=(
  git
  build-essential libudev-dev libegl-dev libgles-dev libx11-xcb-dev
  libpulse-dev libasound2-dev
  libavcodec-dev libavdevice-dev libavformat-dev libdrm-common libdrm-dev libdrm2 libegl1-mesa-dev libfreetype6-dev libgbm-dev
  libgles2 libgles2-mesa libgles2-mesa-dev
  libsdl-image1.2-dev libsdl2-dev libswresample-dev libswscale-dev
  libv4l-dev libxkbcommon-dev libxml2-dev yasm zlib1g-dev
  # Debian >= 12
  libswresample-dev
)

declare -r APT_START=$(date +%s)
apt update
apt install -y "${DEPS[@]}"
declare -r APT_END=$(date +%s)

declare -r REPO_URL="https://github.com/libretro/RetroArch"
declare -r REPO_TAG="v1.15.0"

declare -r CLONE_START=$(date +%s)
if [ ! -d "${RETRO_HOME_DIR}/RetroArch" ]; then
  git clone "${REPO_URL}" -b "${REPO_TAG}" "${RETRO_HOME_DIR}/RetroArch"
else
  echo "RetroArch source already exists at ${RETRO_HOME_DIR}/RetroArch, skipping clone."
fi
declare -r CLONE_END=$(date +%s)

chown -R "${RETRO_USER}":"${RETRO_USER}" "${RETRO_HOME_DIR}/RetroArch"

# Build as retro user
declare -r BUILD_START=$(date +%s)
echo "[INFO] Clone completed and compilation starting at $(date --iso-8601=seconds)"
su - "${RETRO_USER}" -c \
  "cd ~/RetroArch \
   && ./configure --disable-videocore --disable-opengl1 --enable-opengles --enable-floathard \
   && make -j\"$(nproc)\""
declare -r BUILD_END=$(date +%s)
echo "[INFO] Compilation finished at $(date --iso-8601=seconds)"

declare -r APT_DURATION=$((APT_END - APT_START))
declare -r CLONE_DURATION=$((CLONE_END - CLONE_START))
declare -r BUILD_DURATION=$((BUILD_END - BUILD_START))
declare -r TOTAL_DURATION=$((BUILD_END - APT_START))
declare -r HOURS=$((BUILD_DURATION/3600))
declare -r MINUTES=$(((BUILD_DURATION%3600)/60))
declare -r SECONDS=$((BUILD_DURATION%60))
declare -r CLONE_HOURS=$((CLONE_DURATION/3600))
declare -r CLONE_MINUTES=$(((CLONE_DURATION%3600)/60))
declare -r CLONE_SECONDS=$((CLONE_DURATION%60))
declare -r APT_HOURS=$((APT_DURATION/3600))
declare -r APT_MINUTES=$(((APT_DURATION%3600)/60))
declare -r APT_SECONDS=$((APT_DURATION%60))

echo   "=========================================="
echo   "RetroArch build summary:"
echo   "  • Clone start:                  $(date --iso-8601=seconds -d @"${CLONE_START}")"
echo   "  • Clone end:                    $(date --iso-8601=seconds -d @"${BUILD_START}")"
echo   "  • Compilation start:            $(date --iso-8601=seconds -d @"${BUILD_START}")"
echo   "  • Compilation end:              $(date --iso-8601=seconds -d @"${BUILD_END}")"
printf "  • APT time:                     %02d:%02d:%02d (HH:MM:SS)\n" "${APT_HOURS}" "${APT_MINUTES}" "${APT_SECONDS}"
printf "  • Clone time:                   %02d:%02d:%02d (HH:MM:SS)\n" "${CLONE_HOURS}" "${CLONE_MINUTES}" "${CLONE_SECONDS}"
printf "  • Build time:                   %02d:%02d:%02d (HH:MM:SS)\n" "${HOURS}" "${MINUTES}" "${SECONDS}"
printf "  • Total time:                   %02d:%02d:%02d (HH:MM:SS)\n" "$((TOTAL_DURATION/3600))" "$(((TOTAL_DURATION%3600)/60))" "$((TOTAL_DURATION%60))"
echo   "=========================================="