Red Bear OS — microkernel OS in Rust, based on Redox

Derivative of Redox OS (https://www.redox-os.org) adding:
- AMD GPU driver (amdgpu) via LinuxKPI compat layer
- ext4 filesystem support (ext4d scheme daemon)
- ACPI fixes for AMD bare metal (x2APIC, DMAR, IVRS, MCFG)
- Custom branding (hostname, os-release, boot identity)

Build system is full upstream Redox with RBOS overlay in local/.
Patches for kernel, base, and relibc are symlinked from local/patches/
and protected from make clean/distclean. Custom recipes live in
local/recipes/ with symlinks into the recipes/ search path.

Build:  make all CONFIG_NAME=redbear-full
Sync:   ./local/scripts/sync-upstream.sh

recipes/core/base/recipe.toml

@@ -0,0 +1,76 @@
+[source]
+git = "https://gitlab.redox-os.org/redox-os/base.git"
+
+[build]
+template = "custom"
+script = """
+mkdir -pv "${COOKBOOK_STAGE}/usr/bin"
+for package in audiod ipcd ptyd; do
+    "${COOKBOOK_CARGO}" build \
+        --manifest-path "${COOKBOOK_SOURCE}/${package}/Cargo.toml" \
+        ${build_flags}
+    cp -v \
+        "target/${TARGET}/${build_type}/${package}" \
+        "${COOKBOOK_STAGE}/usr/bin/${package}"
+done
+
+"${COOKBOOK_CARGO}" build \
+    --manifest-path "${COOKBOOK_SOURCE}/netstack/Cargo.toml" \
+    ${build_flags}
+cp -v \
+    "target/${TARGET}/${build_type}/smolnetd" \
+    "${COOKBOOK_STAGE}/usr/bin/smolnetd"
+
+# Drivers that are built on all architectures, and NOT in drivers-initfs
+BINS=(
+    e1000d
+    ihdad
+    ihdgd
+    ixgbed
+    pcid
+    pcid-spawner
+    rtl8139d
+    rtl8168d
+    usbctl
+    usbhidd
+    usbhubd
+    usbscsid
+    virtio-netd
+    xhcid
+    inputd
+    redoxerd
+)
+
+# Add additional drivers to the list to build, that are not in drivers-initfs
+# depending on the target architecture
+case "${TARGET}" in
+    i586-unknown-redox | i686-unknown-redox | x86_64-unknown-redox)
+        BINS+=(ac97d bgad sb16d vboxd)
+        ;;
+    *)
+        ;;
+esac
+
+#Build each driver in the list
+mkdir -pv "${COOKBOOK_STAGE}/usr/bin" "${COOKBOOK_STAGE}/usr/lib/drivers"
+export CARGO_PROFILE_RELEASE_OPT_LEVEL=s
+export CARGO_PROFILE_RELEASE_PANIC=abort
+"${COOKBOOK_CARGO}" build ${build_flags} \
+    --manifest-path "${COOKBOOK_SOURCE}/Cargo.toml" \
+    $(for bin in "${BINS[@]}"; do echo "-p" "${bin}"; done)
+for bin in "${BINS[@]}"
+do
+    if [[ "${bin}" == "inputd" || "${bin}" == "pcid" || "${bin}" == "pcid-spawner" || "${bin}" == "redoxerd" ]]; then
+        cp -v "target/${TARGET}/${build_type}/${bin}" "${COOKBOOK_STAGE}/usr/bin"
+    else
+        cp -v "target/${TARGET}/${build_type}/${bin}" "${COOKBOOK_STAGE}/usr/lib/drivers"
+    fi
+done
+
+mkdir -pv "${COOKBOOK_STAGE}/lib/pcid.d"
+${FIND} "${COOKBOOK_SOURCE}/drivers" -maxdepth 3 -type f -name 'config.toml' | while read conf
+do
+    driver="$(basename "$(dirname "$conf")")"
+    cp -v "$conf" "${COOKBOOK_STAGE}/lib/pcid.d/$driver.toml"
+done
+"""