Wren Core Python Binding

Python bindings for wren-core, the Rust semantic engine behind Wren Engine. Built with PyO3 and Maturin.

Wren Engine translates SQL queries through a semantic layer (MDL - Modeling Definition Language) and executes them against 22+ data sources (PostgreSQL, BigQuery, Snowflake, etc.).

Installation

pip install wren-core-py

Requires Python >= 3.11.

Pre-built wheels are available for:

• Linux x86_64
• macOS x86_64 / ARM64 (Apple Silicon)
• Windows x86_64

Linux ARM64 wheels are not yet available. To use on that platform, build from source (requires Rust toolchain).

Quick Start

from wren_core import SessionContext, to_manifest

# Load an MDL manifest from a base64-encoded JSON string
base64_mdl_json = "<your-base64-encoded-mdl-json>"
manifest = to_manifest(base64_mdl_json)

# Create a session context for query planning
ctx = SessionContext(manifest, remote_functions=[])

# Transform a SQL query through the semantic layer
planned_sql = ctx.transform_sql("SELECT * FROM my_model")

Developer Guide

Environment Setup

• Install Rust and Cargo
• Install Python
• Install uv
• Install casey/just

Test and Build

After installing casey/just, you can use the following commands:

• just install — Create Python venv and install dependencies.
• just develop — Build the Rust package for local development (required before running Python tests).
• just test-rs — Run Rust tests only.
• just test-py — Run Python tests only.
• just test — Run both Rust and Python tests.
• just build — Build the Python wheel. Output goes to target/wheels/.

Coding Style

Format via just format.

Publishing

See scripts/publish.sh for local publishing to PyPI/TestPyPI:

./scripts/publish.sh --build    # Build wheel only
./scripts/publish.sh --test     # Build + publish to TestPyPI
./scripts/publish.sh            # Build + publish to PyPI

License

Apache-2.0