PoSpace Reference Implementation (CHIP)

This repository provides a public reference implementation of the new Proof of Space (“PoSpace”) format, as defined in CHIP-48. It includes:

• lib/pos/ — core Proof of Space header‑only library (<pos/...>)
• lib/common/ — header‑only utilities (<common/...>)
• lib/fse/ — vendored FSE compression library
• tools/src/plotter/ — example C++ plotter executable using the above
• tools/src/solver/ - solver benchmarking and testing
• tools/src/prover/ - finding proofs given challenges

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Features

• Header‑only, C++20 PoSpace core (ProofCore, hashing, parameters, validator, etc.)
• Example plotter tool demonstrating the plot pipeline and writing a plot
• Solver tool for benchmarking solve times on CPUs.

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Prerequisites

• A C++20‑capable compiler
• CMake ≥ 3.15
• make (or your preferred build tool)
• A Unix‑style shell (Linux/macOS) or PowerShell/Bash on Windows

Building

1. Clone the repo:

   git clone https://github.com/Chia-Network/pos2-chip.git

   cd pos2-chip

2. Build

   Option A: Use the helper script

   ./build-release.sh

   Option B: Use CMake directly

   First, build with Release mode to enable optimizations:

   cmake -B build -DCMAKE_BUILD_TYPE=Release .

   Next, compile:

   Linux:

   cmake --build build -j$(nproc)

   macOS:

   cmake --build build -j$(sysctl -n hw.logicalcpu)

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Running the Plotter

From the root of your build directory, invoke the plotter executable:

./build/src/tools/plotter/plotter <k>

By default it uses the sample plot ID and parameters defined in tools/plotter/src/main.cpp. To customize, edit that file or supply your own main() implementation.

About strength

strength influences the effective plot filter. Higher strength, means that your plot will be accessed less frequently for responding to challenges.

Examples

To use k=28:

./build/src/tools/plotter/plotter test 28 2

To use k=28 and sub_k=20

./build/plotter 28 20

Running the Solver

Run the solver executable with one of the two modes:

Coming soon.

Benchmark Mode

./build/solver benchmark <k-size>

Where <k-size> is an integer value for the solver’s k parameter (e.g. 28).

Example:

./build/solver benchmark 32

Outputs timing and performance metrics for reconstructing proofs.

Prove Mode

Reads the plot, prints its parameters, and runs the a chaining test for getting and solving for a full proof.

Note

Currently the solver does not accept a challenge to choose a proof from the plot. Coming soon (TM).

./build/solver prove <plot-file>

Where <plot-file> is the path to a plot file to test.

Example:

./build/solver prove /path/to/plot.bin

Note

Plot files are changing frequently, so use the plotter to generate a new plot to then test it.

Tests

To build the tests, set the option -DCP_BUILD_TESTS=ON when configuring.

Example:

cmake -B build -DCP_BUILD_TESTS=ON .

Or you can use the run-tests.sh script

./run-tests.sh

See the run-tests.sh script for more documentation.

Note

Building tests is enabled by default when building from CI.