DietPi
UART over usb
(OTG guide
#/boot/config.txt
# Note To Self, NEVER enable L2 cache, breaks most X based applications that were not compiled with L2 cache enabled.
dtoverlay=dwc2
#i2c rtc
dtoverlay=i2c-rtc,ds3231
#/boot/cmdline.txt
dwc_otg.lpm_enable=0 console=serial0,115200 console=tty1 root=PARTUUID=b8ef7a27-02 rootfstype=ext4 elevator=deadline fsck.repair=yes rootwait modules-load=dwc2,g_serial
Alpine Linux
gnupg-root on a RPI zero (without w)
Create a microsd card with two partitions. Both with ext4, one for the readonly part, the other one for rw.
Preload some useful packages.
edit cmdline.txt and usercfg.txt
attach uart TTL adapter
run setup-alpine
mount /dev/mmcblk0p2 /mnt/
apk add --allow-untrusted sysfsutils-2.1.0-r8.apk
setup-disk -m sys /mnt