doc/README.md

Minimal ISO builder (Docker)

Files created:

• Dockerfile — Debian-based builder using grub-mkrescue/xorriso
• build_iso.sh — builds a bootable ISO from ./iso/ tree
• iso/boot/... — placeholder kernel/initrd, grub.cfg and installer.sh

How it works (recommended flow)

Windows-native builder (new):

• Run .\iso_builder\build_iso_windows.ps1 from an elevated PowerShell session.
• You may pass a kernel path explicitly: .\build_iso_windows.ps1 -KernelPath "C:\path\to\vmlinuz".
• If no kernel is found and no -KernelPath is provided, the script attempts to download a TinyCore vmlinuz fallback (network required).
• The script builds a BusyBox-based initramfs (via mkinitramfs.py) and assembles a bootable ISO.

Docker builder (unchanged):

1. Place your kernel + initrd into iso_builder/iso/boot/ as vmlinuz and initrd.img (or let the Docker builder fetch a kernel).
2. Edit iso/boot/grub/grub.cfg if you want custom kernel cmdline.
3. Build the Docker image and run it to produce mini-installer.iso:
   • docker build -t mini-iso-builder iso_builder
   • docker run --rm -v "%CD%/iso_builder/out:/out" mini-iso-builder
   • Result: iso_builder/out/mini-installer.iso on the host (UEFI + BIOS bootable)

Notes / limitations

• The Windows builder will attempt to use oscdimg.exe (Windows ADK) to create the ISO. If oscdimg is not present the script will attempt a Python/pycdlib fallback.
• If mcore/x86drv/v4.0 (MS-DOS v4.0 sources) is present in the workspace, the Windows builder will copy a trimmed offline package into iso/extra/msdos_v4.0 and add an informational GRUB menu entry. This package is for offline reference/source only and is not directly bootable by GRUB.
• The installer is intentionally minimal (file copy + partitioning). For fully unattended, enable grub-install during the install step or run it manually in the VM once files are copied.
• If you want me to include grub-install into the installer step and perform full bootloader installation automatically, say so and I'll add it.