Environment variables

Langflow lets you configure a number of settings using environment variables.

Configure environment variables

Langflow recognizes supported environment variables from the following sources:

• Environment variables that you've set in your terminal.
• Environment variables that you've imported from a .env file using the --env-file option in the Langflow CLI.

You can choose to use one source exclusively, or use both sources together. If you choose to use both sources together, be aware that environment variables imported from a .env file take precedence over those set in your terminal.

Set environment variables in your terminal

Run the following commands to set environment variables for your current terminal session:

Linux or macOS

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export VARIABLE_NAME='VALUE'

Windows

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set VARIABLE_NAME='VALUE'

Docker

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docker run -it --rm \

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-p 7860:7860 \

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-e VARIABLE_NAME='VALUE' \

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langflowai/langflow:latest

When you start Langflow, it looks for environment variables that you've set in your terminal. If it detects a supported environment variable, then it automatically adopts the specified value, subject to precedence rules.

Import environment variables from a .env file

1. Create a .env file and open it in your preferred editor.

2. Add your environment variables to the file:

   
   

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   VARIABLE_NAME='VALUE'

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   VARIABLE_NAME='VALUE'

   
   
   tip

   The Langflow project includes a .env.example file to help you get started. You can copy the contents of this file into your own .env file and replace the example values with your own preferred settings.

3. Save and close the file.

4. Start Langflow using the --env-file option to define the path to your .env file:

   Local

   
   

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   python -m langflow run --env-file .env

   
   

   Docker

   
   

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   docker run -it --rm \

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   -p 7860:7860 \

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   --env-file .env \

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   langflowai/langflow:latest

   
   

On startup, Langflow imports the environment variables from your .env file, as well as any that you set in your terminal, and adopts their specified values.

Precedence

Environment variables defined in the .env file take precedence over those set in your terminal. That means, if you happen to set the same environment variable in both your terminal and your .env file, Langflow adopts the value from the the .env file.

CLI precedence

Langflow CLI options override the value of corresponding environment variables defined in the .env file as well as any environment variables set in your terminal.

Supported environment variables

The following table lists the environment variables supported by Langflow.

Variable	Format / Values	Default	Description
DO_NOT_TRACK	Boolean	false	If enabled, Langflow will not track telemetry.
LANGFLOW_AUTO_LOGIN	Boolean	true	Enable automatic login for Langflow. Set to false to disable automatic login and require the login form to log into the Langflow UI. Setting to false requires LANGFLOW_SUPERUSER and LANGFLOW_SUPERUSER_PASSWORD to be set.
LANGFLOW_AUTO_SAVING	Boolean	true	Enable flow auto-saving. See --auto-saving option.
LANGFLOW_AUTO_SAVING_INTERVAL	Integer	1000	Set the interval for flow auto-saving in milliseconds. See --auto-saving-interval option.
LANGFLOW_BACKEND_ONLY	Boolean	false	Only run Langflow's backend server (no frontend). See --backend-only option.
LANGFLOW_CACHE_TYPE	async redis memory disk critical	async	Set the cache type for Langflow. If you set the type to redis, then you must also set the following environment variables: LANGFLOW_REDIS_HOST, LANGFLOW_REDIS_PORT, LANGFLOW_REDIS_DB, and LANGFLOW_REDIS_CACHE_EXPIRE.
LANGFLOW_COMPONENTS_PATH	String	langflow/components	Path to the directory containing custom components. See --components-path option.
LANGFLOW_CONFIG_DIR	String	Linux/WSL: ~/.cache/langflow/ macOS: /Users/<username>/Library/Caches/langflow/ Windows: %LOCALAPPDATA%\langflow\langflow\Cache	Set the Langflow configuration directory where files, logs, and the Langflow database are stored.
LANGFLOW_DATABASE_URL	String	Not set	Set the database URL for Langflow. If not provided, Langflow will use a SQLite database.
LANGFLOW_DATABASE_CONNECTION_RETRY	Boolean	false	If True, Langflow will retry to connect to the database if it fails.
LANGFLOW_DB_POOL_SIZE	Integer	10	DEPRECATED: Use LANGFLOW_DB_CONNECTION_SETTINGS instead. The number of connections to keep open in the connection pool.
LANGFLOW_DB_MAX_OVERFLOW	Integer	20	DEPRECATED: Use LANGFLOW_DB_CONNECTION_SETTINGS instead. The number of connections to allow that can be opened beyond the pool size.
LANGFLOW_DB_CONNECT_TIMEOUT	Integer	20	The number of seconds to wait before giving up on a lock to be released or establishing a connection to the database.
LANGFLOW_DB_CONNECTION_SETTINGS	JSON	Not set	A JSON dictionary to centralize database connection parameters. Example: {"pool_size": 10, "max_overflow": 20}
LANGFLOW_DEV	Boolean	false	Run Langflow in development mode (may contain bugs). See --dev option.
LANGFLOW_FALLBACK_TO_ENV_VAR	Boolean	true	If enabled, global variables set in the Langflow UI fall back to an environment variable with the same name when Langflow fails to retrieve the variable value.
LANGFLOW_FRONTEND_PATH	String	./frontend	Path to the frontend directory containing build files. This is for development purposes only. See --frontend-path option.
LANGFLOW_HEALTH_CHECK_MAX_RETRIES	Integer	5	Set the maximum number of retries for the health check. See --health-check-max-retries option.
LANGFLOW_HOST	String	127.0.0.1	The host on which the Langflow server will run. See --host option.
LANGFLOW_LANGCHAIN_CACHE	InMemoryCache SQLiteCache	InMemoryCache	Type of cache to use. See --cache option.
LANGFLOW_LOG_LEVEL	DEBUG INFO WARNING ERROR CRITICAL	INFO	Set the logging level for Langflow.
LANGFLOW_LOG_FILE	String	Not set	Path to the log file. If not set, logs will be written to stdout.
LANGFLOW_MAX_FILE_SIZE_UPLOAD	Integer	100	Set the maximum file size for the upload in megabytes. See --max-file-size-upload option.
LANGFLOW_MCP_SERVER_ENABLED	Boolean	true	If set to False, Langflow will not enable the MCP server.
LANGFLOW_MCP_SERVER_ENABLE_PROGRESS_NOTIFICATIONS	Boolean	false	If set to True, Langflow will send progress notifications in the MCP server.
LANGFLOW_NEW_USER_IS_ACTIVE	Boolean	false	When enabled, new users are automatically activated and can log in without requiring explicit activation by the superuser.
LANGFLOW_OPEN_BROWSER	Boolean	false	Open the system web browser on startup. See --open-browser option.
LANGFLOW_PORT	Integer	7860	The port on which the Langflow server will run. The server automatically selects a free port if the specified port is in use. See --port option.
LANGFLOW_PROMETHEUS_ENABLED	Boolean	false	Expose Prometheus metrics.
LANGFLOW_PROMETHEUS_PORT	Integer	9090	Set the port on which Langflow exposes Prometheus metrics.
LANGFLOW_REDIS_CACHE_EXPIRE	Integer	3600	See LANGFLOW_CACHE_TYPE.
LANGFLOW_REDIS_DB	Integer	0	See LANGFLOW_CACHE_TYPE.
LANGFLOW_REDIS_HOST	String	localhost	See LANGFLOW_CACHE_TYPE.
LANGFLOW_REDIS_PORT	String	6379	See LANGFLOW_CACHE_TYPE.
LANGFLOW_REMOVE_API_KEYS	Boolean	false	Remove API keys from the projects saved in the database. See --remove-api-keys option.
LANGFLOW_SAVE_DB_IN_CONFIG_DIR	Boolean	false	Save the Langflow database in LANGFLOW_CONFIG_DIR instead of in the Langflow package directory. Note, when this variable is set to default (false), the database isn't shared between different virtual environments and the database is deleted when you uninstall Langflow.
LANGFLOW_SECRET_KEY	String	Auto-generated	Key used for encrypting sensitive data like API keys. If not provided, a secure key will be auto-generated. For production environments with multiple instances, you should explicitly set this to ensure consistent encryption across instances.
LANGFLOW_STORE	Boolean	true	Enable the Langflow Store. See --store option.
LANGFLOW_STORE_ENVIRONMENT_VARIABLES	Boolean	true	Store environment variables as global variables in the database.
LANGFLOW_SUPERUSER	String	langflow	Set the name for the superuser. Required if LANGFLOW_AUTO_LOGIN is set to false. See superuser --username option.
LANGFLOW_SUPERUSER_PASSWORD	String	langflow	Set the password for the superuser. Required if LANGFLOW_AUTO_LOGIN is set to false. See superuser --password option.
LANGFLOW_VARIABLES_TO_GET_FROM_ENVIRONMENT	String	Not set	Comma-separated list of environment variables to get from the environment and store as global variables.
LANGFLOW_LOAD_FLOWS_PATH	String	Not set	Path to a directory containing flow JSON files to be loaded on startup. Note that this feature only works if LANGFLOW_AUTO_LOGIN is enabled.
LANGFLOW_WORKER_TIMEOUT	Integer	300	Worker timeout in seconds. See --worker-timeout option.
LANGFLOW_WORKERS	Integer	1	Number of worker processes. See --workers option.

Configure .env, override.conf, and tasks.json files

The following examples show how to configure Langflow using environment variables in different scenarios.

.env File

The .env file is a text file that contains key-value pairs of environment variables.

Create or edit a file named .env in your project root directory and add your configuration:

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DO_NOT_TRACK=true

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LANGFLOW_AUTO_LOGIN=false

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LANGFLOW_AUTO_SAVING=true

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LANGFLOW_AUTO_SAVING_INTERVAL=1000

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LANGFLOW_BACKEND_ONLY=false

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LANGFLOW_CACHE_TYPE=async

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LANGFLOW_COMPONENTS_PATH=/path/to/components/

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LANGFLOW_CONFIG_DIR=/path/to/config/

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LANGFLOW_DATABASE_URL=postgresql://user:password@localhost:5432/langflow

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LANGFLOW_DEV=false

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LANGFLOW_FALLBACK_TO_ENV_VAR=false

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LANGFLOW_HEALTH_CHECK_MAX_RETRIES=5

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LANGFLOW_HOST=127.0.0.1

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LANGFLOW_LANGCHAIN_CACHE=InMemoryCache

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LANGFLOW_MAX_FILE_SIZE_UPLOAD=10000

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LANGFLOW_LOG_LEVEL=error

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LANGFLOW_OPEN_BROWSER=false

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LANGFLOW_PORT=7860

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LANGFLOW_REMOVE_API_KEYS=false

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LANGFLOW_SAVE_DB_IN_CONFIG_DIR=true

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LANGFLOW_SECRET_KEY=somesecretkey

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LANGFLOW_STORE=true

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LANGFLOW_STORE_ENVIRONMENT_VARIABLES=true

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LANGFLOW_SUPERUSER=adminuser

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LANGFLOW_SUPERUSER_PASSWORD=adminpass

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LANGFLOW_WORKER_TIMEOUT=60000

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LANGFLOW_WORKERS=3

Systemd service

A systemd service configuration file configures Linux system services.

To add environment variables, create or edit a service configuration file and add an override.conf file. This file allows you to override the default environment variables for the service.

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[Service]

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Environment="DO_NOT_TRACK=true"

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Environment="LANGFLOW_AUTO_LOGIN=false"

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Environment="LANGFLOW_AUTO_SAVING=true"

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Environment="LANGFLOW_AUTO_SAVING_INTERVAL=1000"

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Environment="LANGFLOW_BACKEND_ONLY=false"

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Environment="LANGFLOW_CACHE_TYPE=async"

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Environment="LANGFLOW_COMPONENTS_PATH=/path/to/components/"

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Environment="LANGFLOW_CONFIG_DIR=/path/to/config"

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Environment="LANGFLOW_DATABASE_URL=postgresql://user:password@localhost:5432/langflow"

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Environment="LANGFLOW_DEV=false"

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Environment="LANGFLOW_FALLBACK_TO_ENV_VAR=false"

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Environment="LANGFLOW_HEALTH_CHECK_MAX_RETRIES=5"

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Environment="LANGFLOW_HOST=127.0.0.1"

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Environment="LANGFLOW_LANGCHAIN_CACHE=InMemoryCache"

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Environment="LANGFLOW_MAX_FILE_SIZE_UPLOAD=10000"

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Environment="LANGFLOW_LOG_ENV=container_json"

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Environment="LANGFLOW_LOG_FILE=logs/langflow.log"

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Environment="LANGFLOW_LOG_LEVEL=error"

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Environment="LANGFLOW_OPEN_BROWSER=false"

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Environment="LANGFLOW_PORT=7860"

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Environment="LANGFLOW_REMOVE_API_KEYS=false"

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Environment="LANGFLOW_SAVE_DB_IN_CONFIG_DIR=true"

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Environment="LANGFLOW_SECRET_KEY=somesecretkey"

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Environment="LANGFLOW_STORE=true"

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Environment="LANGFLOW_STORE_ENVIRONMENT_VARIABLES=true"

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Environment="LANGFLOW_SUPERUSER=adminuser"

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Environment="LANGFLOW_SUPERUSER_PASSWORD=adminpass"

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Environment="LANGFLOW_WORKER_TIMEOUT=60000"

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Environment="LANGFLOW_WORKERS=3"

For more information on systemd, see the Red Hat documentation.

VSCode tasks.json

The tasks.json file located in .vscode/tasks.json is a configuration file for development environments using Visual Studio Code.

Create or edit the .vscode/tasks.json file in your project root:

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{

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"version": "2.0.0",

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"options": {

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"env": {

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"DO_NOT_TRACK": "true",

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"LANGFLOW_AUTO_LOGIN": "false",

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"LANGFLOW_AUTO_SAVING": "true",

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"LANGFLOW_AUTO_SAVING_INTERVAL": "1000",

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"LANGFLOW_BACKEND_ONLY": "false",

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"LANGFLOW_CACHE_TYPE": "async",

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"LANGFLOW_COMPONENTS_PATH": "D:/path/to/components/",

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"LANGFLOW_CONFIG_DIR": "D:/path/to/config/",

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"LANGFLOW_DATABASE_URL": "postgresql://postgres:password@localhost:5432/langflow",

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"LANGFLOW_DEV": "false",

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"LANGFLOW_FALLBACK_TO_ENV_VAR": "false",

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"LANGFLOW_HEALTH_CHECK_MAX_RETRIES": "5",

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"LANGFLOW_HOST": "localhost",

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"LANGFLOW_LANGCHAIN_CACHE": "InMemoryCache",

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"LANGFLOW_MAX_FILE_SIZE_UPLOAD": "10000",

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"LANGFLOW_LOG_ENV": "container_csv",

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"LANGFLOW_LOG_FILE": "langflow.log",

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"LANGFLOW_LOG_LEVEL": "error",

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"LANGFLOW_OPEN_BROWSER": "false",

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"LANGFLOW_PORT": "7860",

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"LANGFLOW_REMOVE_API_KEYS": "true",

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"LANGFLOW_SAVE_DB_IN_CONFIG_DIR": "false",

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"LANGFLOW_SECRET_KEY": "somesecretkey",

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"LANGFLOW_STORE": "true",

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"LANGFLOW_STORE_ENVIRONMENT_VARIABLES": "true",

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"LANGFLOW_SUPERUSER": "adminuser",

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"LANGFLOW_SUPERUSER_PASSWORD": "adminpass",

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"LANGFLOW_WORKER_TIMEOUT": "60000",

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"LANGFLOW_WORKERS": "3"

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}

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},

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"tasks": [

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{

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"label": "langflow backend",

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"type": "shell",

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"command": ". ./langflownightly/Scripts/activate && langflow run",

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"isBackground": true,

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"problemMatcher": []

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}

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]

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}

To run Langflow using the above VSCode tasks.json file, in the VSCode command palette, select Tasks: Run Task > langflow backend.