UltiHash Patches

Fork of https://github.com/UltiHash/core/ with patches aiming to keep the project alive.

Overview

This repository is a fork of UltiHash Core. It extends the upstream codebase with additional patches and modifications maintained independently.

The fork is not intended to contribute patches upstream. Changes made here are maintained separately and licensed under different terms than the original project.

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Building

Requirements

apt install -y cmake clang-18 ninja libpq-dev postgresql liblmdb++-dev \
    protobuf-compiler-grpc libprotoc-dev libgrpc++-dev libgrpc-dev

Also install:

• Boost 1.88 or newer

Building

git submodule update --init --recursive && \
cmake --preset default &&
cmake --build build

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Licensing

This repository contains code under two distinct licenses, separated by a git tag: ultihash-apache-2.0-license

Apache License 2.0 — upstream code

All code up to and including tag [ultihash-apache-2.0-license] originates from UltiHash Core and is licensed under the Apache License 2.0.

See LICENSE-APACHE for the full license text.

GNU General Public License v3.0 — fork additions

All modifications, additions, and new files introduced after tag ultihash-apache-2.0-license are licensed under the GNU General Public License v3.0.

See LICENSE-GPL for the full license text.

Copyright (c) 2026 Stefan Jank

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License Boundary

The tag ultihash-apache-2.0-license marks the exact point at which the license boundary occurs:

[upstream history] ──── [ultihash-apache-2.0-license] ──── [GPL v3 patches]
                         Apache 2.0 ↑                       ↑ GPL v3

To inspect the boundary:

# Show the tag
git show ultihash-apache-2.0-license

# List all commits after the tag (GPL v3 territory)
git log ultihash-apache-2.0-license..HEAD --oneline

# List all commits up to and including the tag (Apache 2.0 territory)
git log ultihash-apache-2.0-license --oneline

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File-Level Copyright Headers

New files introduced after ultihash-apache-2.0-license carry the following header:

// Copyright (c) 2026 Stefan Jank
// SPDX-License-Identifier: GPL-3.0-only

Files from the upstream codebase that were modified after ultihash-apache-2.0-license carry both copyright notices:

// Copyright (c) [UPSTREAM YEAR] [UPSTREAM AUTHORS]
// Copyright (c) 2026 Stefan Jank — modifications
// SPDX-License-Identifier: GPL-3.0-only

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Upstream Compatibility

The GPL v3 is compatible with the Apache License 2.0 in the following sense:

• The upstream Apache 2.0 code can be combined with GPL v3 additions; the combined work is governed by GPL v3.
• Code introduced after ultihash-apache-2.0-license cannot be incorporated into the upstream Apache 2.0 project or any other Apache 2.0-licensed codebase without relicensing.

This is an intentional design decision to maintain clear separation of intellectual property.

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Syncing with Upstream

This fork does not track or synchronize with the upstream repository. The codebase diverges intentionally from upstream as of tag ultihash-apache-2.0-license.