feat: Add JSTprove backend integration

docs/JSTPROVE_BACKEND.md

@@ -0,0 +1,105 @@
+# JSTprove Backend Integration
+
+## Overview
+
+This document describes the integration of JSTprove as an additional ZK proof backend alongside EZKL in the Dsperse compilation pipeline.
+
+## Features
+
+### 1. JSTprove Backend Support
+- New backend class `JSTprove` in `dsperse/src/backends/JSTprove.py`
+- Uses JSTprove CLI (`jst` command) for circuit compilation, witness generation, proof generation, and verification
+- Compatible with existing EZKL interface for seamless integration
+
+### 2. Flexible Backend Selection
+The compiler now supports three modes:
+
+**Default (Fallback Mode):**
+```bash
+dsperse compile --path model/slices
+```
+- Tries JSTprove first
+- Falls back to EZKL if JSTprove fails
+- Falls back to ONNX (skip ZK compilation) if both fail
+
+**Single Backend:**
+```bash
+dsperse compile --path model/slices --backend jstprove
+dsperse compile --path model/slices --backend ezkl
+```
+
+**Per-Layer Backend Assignment:**
+```bash
+dsperse compile --path model/slices --backend "0,2:jstprove;3-4:ezkl"
+```
+- Layer 0 and 2: Use JSTprove
+- Layer 3 and 4: Use EZKL
+- Unspecified layers use default backend
+
+## Installation
+
+1. Install Open MPI (required for JSTprove):
+   ```bash
+   brew install open-mpi  # macOS
+   # or apt-get install openmpi-bin libopenmpi-dev  # Linux
+   ```
+
+2. Install JSTprove:
+   ```bash
+   uv tool install jstprove
+   # or: pip install jstprove
+   ```
+
+3. Verify installation:
+   ```bash
+   jst --help
+   ```
+
+The `install.sh` script has been updated to automatically install these dependencies.
+
+## File Changes
+
+### New Files
+- `dsperse/src/backends/JSTprove.py` - JSTprove backend implementation
+
+### Modified Files
+- `dsperse/src/cli/compile.py` - Added `--backend` argument
+- `dsperse/src/compile/compiler.py` - Backend selection and fallback logic
+- `dsperse/src/compile/utils/compiler_utils.py` - Support for JSTprove compilation success check
+- `dsperse/src/constants.py` - Added JSTprove command constant
+- `install.sh` - Added Open MPI and JSTprove installation
+- `requirements.txt` - Added mpi4py dependency
+
+## Usage Examples
+
+**Compile all layers with default fallback:**
+```bash
+dsperse compile --path model/slices
+```
+
+**Compile specific layers with mixed backends:**
+```bash
+dsperse compile --path model/slices --layers "0-4" --backend "0,2:jstprove;3-4:ezkl"
+```
+
+**Compile with single backend:**
+```bash
+dsperse compile --path model/slices --backend jstprove
+```
+
+## Backend Comparison
+
+| Feature | JSTprove | EZKL |
+|---------|----------|------|
+| Circuit Format | `.txt` | `.compiled` |
+| Keys | Not required | `vk.key`, `pk.key` |
+| Settings | Dummy JSON | Full settings.json |
+| CLI Command | `jst` | `ezkl` |
+
+## Notes
+
+- JSTprove uses CLI-only interface (no Python package import)
+- Fallback logic ensures compilation continues even if preferred backend fails
+- Metadata tracks which backend was used for each slice
+- All changes maintain backward compatibility with existing EZKL workflows
+