don't use cummingbird as it does not support ramdisk, instead use openrc wich is kinda also lighter than cummingbird

grub-defconfig/payload/boot/grub/grub.cfg

@@ -1,8 +1,8 @@
 set timeout=15
 set default=0
- 
+
 menuentry "Alnux" {
   # you will probably want to change the root below...
-  linux /boot/bzImage noapic root=/dev/sda1 init=/usr/bin/hummingbird
+  linux /boot/bzImage noapic root=/dev/sda1 init=/sbin/openrc-init
   boot
 }

openrc/build

@@ -0,0 +1,4 @@
+wget -O openrc-0.43.3.tar.gz https://github.com/OpenRC/openrc/archive/refs/tags/0.43.3.tar.gz
+tar -xf openrc-0.43.3.tar.gz
+cd openrc-0.43.3
+make install BRANDING=\"Alnux/$(uname -s)\" SH=/bin/sh DESTDIR="$1"/sbin/openrc  PREFIX="$1"

openrc/package

@@ -0,0 +1,5 @@
+pkg_config_deploy=true
+pkg_config_ver="0.43.3"
+pkg_config_name="openrc"
+pkg_config_makedepends=""
+pkg_config_depends="make"