How to Set Up a LangGraph Application for Deployment¶
A LangGraph application must be configured with a LangGraph API configuration file in order to be deployed to LangGraph Cloud (or to be self-hosted). This how-to guide discusses the basic steps to setup a LangGraph application for deployment using requirements.txt to specify project dependencies.
This walkthrough is based on this repository, which you can play around with to learn more about how to setup your LangGraph application for deployment.
Setup with pyproject.toml
If you prefer using poetry for dependency management, check out this how-to guide on using pyproject.toml for LangGraph Cloud.
Setup with a Monorepo
If you are interested in deploying a graph located inside a monorepo, take a look at this repository for an example of how to do so.
The final repo structure will look something like this:
my-app/
├── my_agent # all project code lies within here
│ ├── utils # utilities for your graph
│ │ ├── __init__.py
│ │ ├── tools.py # tools for your graph
│ │ ├── nodes.py # node functions for you graph
│ │ └── state.py # state definition of your graph
│ ├── requirements.txt # package dependencies
│ ├── __init__.py
│ └── agent.py # code for constructing your graph
├── .env # environment variables
└── langgraph.json # configuration file for LangGraph
After each step, an example file directory is provided to demonstrate how code can be organized.
Specify Dependencies¶
Dependencies can optionally be specified in one of the following files: pyproject.toml, setup.py, or requirements.txt. If none of these files is created, then dependencies can be specified later in the LangGraph API configuration file.
The dependencies below will be included in the image, you can also use them in your code, as long as with a compatible version range:
langgraph>=0.2.56,<0.3.0
langgraph-checkpoint>=2.0.5,<3.0
langchain-core>=0.2.38,<0.4.0
langsmith>=0.1.63
orjson>=3.9.7
httpx>=0.25.0
tenacity>=8.0.0
uvicorn>=0.26.0
sse-starlette>=2.1.0
uvloop>=0.18.0
httptools>=0.5.0
jsonschema-rs>=0.16.3
croniter>=1.0.1
structlog>=23.1.0
redis>=5.0.0,<6.0.0
Example requirements.txt file:
Example file directory:
my-app/
├── my_agent # all project code lies within here
│ └── requirements.txt # package dependencies
Specify Environment Variables¶
Environment variables can optionally be specified in a file (e.g. .env). See the Environment Variables reference to configure additional variables for a deployment.
Example .env file:
Example file directory:
my-app/
├── my_agent # all project code lies within here
│ └── requirements.txt # package dependencies
└── .env # environment variables
Define Graphs¶
Implement your graphs! Graphs can be defined in a single file or multiple files. Make note of the variable names of each CompiledGraph to be included in the LangGraph application. The variable names will be used later when creating the LangGraph API configuration file.
Example agent.py file, which shows how to import from other modules you define (code for the modules is not shown here, please see this repo to see their implementation):
# my_agent/agent.py
from typing import Literal
from typing_extensions import TypedDict
from langgraph.graph import StateGraph, END, START
from my_agent.utils.nodes import call_model, should_continue, tool_node # import nodes
from my_agent.utils.state import AgentState # import state
# Define the config
class GraphConfig(TypedDict):
model_name: Literal["anthropic", "openai"]
workflow = StateGraph(AgentState, config_schema=GraphConfig)
workflow.add_node("agent", call_model)
workflow.add_node("action", tool_node)
workflow.add_edge(START, "agent")
workflow.add_conditional_edges(
"agent",
should_continue,
{
"continue": "action",
"end": END,
},
)
workflow.add_edge("action", "agent")
graph = workflow.compile()
API Reference: StateGraph | END | START
Assign CompiledGraph to Variable
The build process for LangGraph Cloud requires that the CompiledGraph object be assigned to a variable at the top-level of a Python module (alternatively, you can provide a function that creates a graph).
Example file directory:
my-app/
├── my_agent # all project code lies within here
│ ├── utils # utilities for your graph
│ │ ├── __init__.py
│ │ ├── tools.py # tools for your graph
│ │ ├── nodes.py # node functions for you graph
│ │ └── state.py # state definition of your graph
│ ├── requirements.txt # package dependencies
│ ├── __init__.py
│ └── agent.py # code for constructing your graph
└── .env # environment variables
Create LangGraph API Config¶
Create a LangGraph API configuration file called langgraph.json. See the LangGraph CLI reference for detailed explanations of each key in the JSON object of the configuration file.
Example langgraph.json file:
{
"dependencies": ["./my_agent"],
"graphs": {
"agent": "./my_agent/agent.py:graph"
},
"env": ".env"
}
Note that the variable name of the CompiledGraph appears at the end of the value of each subkey in the top-level graphs key (i.e. :<variable_name>).
Configuration Location
The LangGraph API configuration file must be placed in a directory that is at the same level or higher than the Python files that contain compiled graphs and associated dependencies.
Example file directory:
my-app/
├── my_agent # all project code lies within here
│ ├── utils # utilities for your graph
│ │ ├── __init__.py
│ │ ├── tools.py # tools for your graph
│ │ ├── nodes.py # node functions for you graph
│ │ └── state.py # state definition of your graph
│ ├── requirements.txt # package dependencies
│ ├── __init__.py
│ └── agent.py # code for constructing your graph
├── .env # environment variables
└── langgraph.json # configuration file for LangGraph
Next¶
After you setup your project and place it in a github repo, it's time to deploy your app.