NextCore

Userland tooling for the NextCore boot picker: a prebuilt EFI binary, an EFI folder generator, and a USB creator. Nothing here requires a toolchain — Python 3.9+ and, on Windows, PowerShell 5.1+.

This repository is deliberately small. It contains only what an end user needs to put NextCore on a USB stick behind OpenCore. Source code, research notes, probes and validation harnesses live in a separate private repository and are not published here.

bin/NEXTCORE/BOOTX64.EFI   NextCore picker (x86_64 UEFI application)
bin/MANIFEST.sha256        hash of the shipped binary
bin/release.json           version, build features, evidence status
tools/make_efi.py          EFI folder generator (OpenCore + NextCore + config.plist)
tools/make-usb.ps1         USB creator for Windows
profiles/*.json            hardware profiles consumed by make_efi.py

What it produces

tools/make_efi.py downloads the pinned official OpenCore RELEASE (SHA-256 checked, cached under cache/), generates config.plist from OpenCore's own Docs/Sample.plist plus a profile, validates it with ocvalidate, and assembles:

EFI/BOOT/BOOTX64.EFI        OpenCore BOOTx64.efi
EFI/OC/OpenCore.efi
EFI/OC/Drivers/OpenRuntime.efi
EFI/OC/Drivers/OpenHfsPlus.efi
EFI/OC/Tools/OpenShell.efi
EFI/OC/config.plist         generated + ocvalidate-clean
EFI/NEXTCORE/BOOTX64.EFI    NextCore picker (hash-checked against bin/MANIFEST.sha256)

Boot flow: firmware → OpenCore picker → NextCore Picker entry (UEFI Shell is the second entry). OpenCore binaries are never redistributed from this repo; they are fetched from acidanthera/OpenCorePkg at build time.

Quick start

1. Generate the EFI folder

python tools/make_efi.py --profile generic-x64 --out out/generic-x64
# or a hardware-specific profile
python tools/make_efi.py --profile 15igl7 --out out/15igl7

Set real SMBIOS values before booting macOS (placeholders are written otherwise):

python tools/make_efi.py --profile 15igl7 --out out/15igl7 \
  --serial C02XXXXXXXXX --mlb C02XXXXXXXXXXXXXX \
  --uuid 12345678-1234-1234-1234-123456789ABC --rom 112233445566

Outputs: out/<profile>/EFI/, MANIFEST.sha256, efi-receipt.json.

2a. Write a USB stick (Windows)

Run from an elevated PowerShell:

.\tools\make-usb.ps1 -List                              # find the disk number
.\tools\make-usb.ps1 -Profile 15igl7 -DiskNumber 2 -Force   # ERASES disk 2

Creates GPT → 512 MiB FAT32 ESP (NEXTCORE) + exFAT data partition, copies the EFI tree, and re-hashes every file on the stick against MANIFEST.sha256. Refuses boot/system disks and non-USB disks.

To refresh an existing FAT32 ESP without repartitioning:

.\tools\make-usb.ps1 -EfiDir .\out\15igl7 -EspRoot D:\

2b. macOS / Linux

Format the stick GPT with a FAT32 EFI System Partition (macOS: diskutil eraseDisk FAT32 NEXTCORE GPT diskN; Linux: sgdisk + mkfs.vfat -F32), then copy out/<profile>/EFI to the root of that partition and check hashes with sha256sum -c MANIFEST.sha256 from the partition root.

3. Boot

Disable Secure Boot, boot the USB in UEFI mode, choose NextCore Picker in OpenCore.

Profiles

Profile	Target	Notes
generic-x64	any x86_64 UEFI machine	Sample.plist quirk defaults, no ACPI, no kexts, iMacPro1,1 placeholder
15igl7	Lenovo IdeaPad 1 15IGL7 (Gemini Lake, UHD 600/605)	1366x768 text renderer, USB ownership quirks, iGPU framebuffer hint, no kexts (no AVX2)

A profile is a JSON file: set is a map of dotted plist paths to values ({"$data": "<base64>"} for <data>), drivers/tools list files taken from the OpenCore release. Copy one and edit it; make_efi.py --profile path/to/file.json accepts a path.

Verify what you got

cd bin && sha256sum -c MANIFEST.sha256

bin/release.json records the binary's SHA-256, target (x86_64-unknown-uefi), build features (apfs-jumpstart, console-control) and the evidence status.

What this is not

• Not a macOS boot claim. macos_boot_verified is false in every receipt this repo writes. Reaching the NextCore picker proves firmware load and OpenCore chain-load, nothing more.
• Not installer media. The exFAT data partition is plain storage. A BaseSystem.dmg copied there is not bootable Recovery; real Recovery/installer volumes must be created on macOS (createinstallmedia).
• Not a supported-hardware list. The 15igl7 profile documents a machine that lacks AVX2 and has no macOS graphics driver; it exists to reach the picker, not to run macOS.
• No Apple assets, no source. Only project-built EFI and OpenCore release files are used.

License

See LICENSE.txt. Binary redistribution is permitted under the listed conditions. OpenCore is © Acidanthera, BSD-3-Clause, downloaded from its official releases.