Skip to main content

Install custom dependencies

Langflow provides optional dependency groups and support for custom dependencies to extend Langflow functionality.

Install optional dependency groups​

Langflow OSS provides optional dependency groups that extend its functionality.

These dependencies are listed in the pyproject.toml file under [project.optional-dependencies].

Install dependency groups using pip's [extras] syntax. For example, to install Langflow with the postgresql dependency group, enter the following command:


_10
uv pip install "langflow[postgresql]"

To install multiple extras, use commas to separate each dependency group:


_10
uv pip install "langflow[deploy,local,postgresql]"

Install custom dependencies​

To install your own custom dependencies in your Langflow environment, add them with your package manager.

If you're working within a cloned Langflow repository, add dependencies with uv add because there is already a pyproject.toml file for uv to reference:


_10
uv add langflow DEPENDENCY

Use a virtual environment to test custom dependencies​

When testing locally, use a virtual environment to isolate your dependencies and prevent conflicts with other Python projects.

For example, if you want to experiment with matplotlib with Langflow:


_10
# Create and activate a virtual environment
_10
uv venv YOUR_LANGFLOW_VENV
_10
source YOUR_LANGFLOW_VENV/bin/activate
_10
_10
# Install langflow and your additional dependency
_10
uv pip install langflow matplotlib

If you're working within a cloned Langflow repository, add dependencies with uv add to reference the existing pyproject.toml file:


_10
uv add langflow matplotlib

Add dependencies to the Langflow project​

When contributing to Langflow itself, add dependencies to the project's configuration.

Langflow uses a workspace with two packages:

  • The main package (root level): For end-user features and main application code
  • The base package (in src/backend/base): For core functionality and shared code

Dependencies can be added in different groups:

  • Regular dependencies: Core functionality needed to run the package
  • Development dependencies: Tools for testing, linting, or debugging are added in the [dependency-groups.dev] section
  • Optional dependencies: Features that users can optionally install are added in the[project.optional-dependencies]

There are three ways to add a package using make commands:

  • Add to main package dependencies (for end-user features):

_10
make add main="matplotlib"

  • Add to development tools (for testing, linting, debugging):

_10
make add devel="matplotlib"

  • Add to base package dependencies (for core functionality):

_10
make add base="matplotlib"

You can also add these dependencies manually to the pyproject.toml file:


_10
[project]
_10
dependencies = [
_10
"matplotlib>=3.8.0"
_10
]

  • Or as an optional dependency:

_10
[project.optional-dependencies]
_10
plotting = [
_10
"matplotlib>=3.8.0",
_10
]

The make commands add the dependency with uv add and update the uv.lock file in the appropriate location.

Search