xian-tech-contracting 1.0.4

Xian Network Python Contracting Engine

xian-contracting

xian-contracting is the Python contract runtime for Xian. It owns contract compilation, secure execution, storage semantics, metering, and the runtime rules that contracts must obey.

Quick Start

Install the runtime:

pip install xian-tech-contracting

If you want contract-side zk proof verification, install the optional zk backend too:

pip install 'xian-tech-contracting[zk]'

The published PyPI package name is xian-tech-contracting. The repo name remains xian-contracting, and the import surface remains contracting.

Submit and call a contract:

from contracting.client import ContractingClient

client = ContractingClient()
client.submit(name="con_token", code=contract_source)
token = client.get_contract("con_token")
token.transfer(amount=100, to="bob")

Access storage directly:

from contracting.storage.driver import Driver

driver = Driver()
driver.set("example.key", "value")
print(driver.get("example.key"))

Principles

• Contracts use Python syntax, but execution rules are consensus-sensitive and intentionally narrower than general Python.
• Metering, storage encoding, import restrictions, and runtime helpers must stay version-aligned across validators.
• Optional native tracing is an implementation detail. The contract model and runtime rules should remain understandable without it.
• Built-in helpers should serve the execution model, not grow into a general convenience framework.

Key Directories

• src/contracting/: runtime, storage, compilation, and stdlib bridge code
• packages/: shared packages such as xian-runtime-types, xian-accounts, the native tracer, and xian-zk
• tests/: unit, integration, and security coverage
• docs/: architecture, backlog, and execution notes

What It Covers

• compilation and linting
• runtime execution and metering
• storage drivers and encoding
• contract-side runtime helpers
• optional native tracing backend
• native zero-knowledge verifier building blocks

Validation

uv sync --group dev
uv run ruff check .
uv run ruff format --check .
uv run pytest

If you change the zk runtime surface or the native verifier package, run:

uv sync --group dev --extra zk
uv run --extra zk pytest -q tests/unit/test_zk_stdlib.py tests/integration/test_zk_bridge.py
cd packages/xian-zk && uv sync --group dev && uv run maturin develop && uv run pytest -q

If you change metering, tracing, storage encoding, or import restrictions, run the relevant tests/security/ and tests/integration/ paths explicitly too.

Related Docs

• AGENTS.md
• docs/ARCHITECTURE.md
• docs/BACKLOG.md
• docs/README.md