Install¶

GuardLayer needs Python 3.10 or later. The core has no runtime dependencies.

pip install guardlayer

Optional extras add heavier layers and integrations. Install only what you use: each one brings third-party packages.

Extra	Adds	Pulls in
`api`	REST API server	FastAPI, uvicorn, pydantic
`signing`	Ed25519-signed audit logs	cryptography
`ml`	transformer prompt-injection classifier	transformers, torch (about 750 MB of model weights on first use)
`embeddings`	semantic similarity and relevance checks	sentence-transformers
`langgraph`	LangGraph / LangChain integration	langgraph
`openai-agents`	OpenAI Agents SDK integration	openai-agents
`toml`	TOML config on Python 3.10	tomli

pip install "guardlayer[api,signing]"

Check the install:

guardlayer --version
guardlayer scan "Ignore all previous instructions."    # prints BLOCK and exits with code 1

From source¶

git clone https://github.com/Lijithvmv/Guard-Layer
cd Guard-Layer
pip install -e ".[dev]"
pytest -q

The image runs the REST API as a non-root user. See Deployment for hardened Compose and Kubernetes setups.

docker build -t guardlayer .
docker run -p 127.0.0.1:8000:8000 -e GUARDLAYER_API_KEY=change-me --read-only --tmpfs /tmp guardlayer