Environment Variables

The MLTK uses the following optional environment variables:


This should be a list of directory paths to search for MLTK models. Each directory path should be delimited with the OS’s path delimiter

  • Windows - Semicolon ;

  • Linux - Colon :

See Model Search Path for more details.


Specify the directory path to the MLTK’s cache directory. If omitted, the MLTK defaults to the directory: ~/.mltk


Specify the path to the user_settings.yaml. If omitted, the settings file points to ~/.mltk/user_settings.yaml.


Set this variable to 1 to indicate that the MLTK is running on a “read-only” file-system. This is useful if te MLTK package is running in a cloud “lambda” function.

When set, the MLTK will only write to the OS’s temporary directory.


This is used by setup.py, the script used to install the MLTK Python package. This may be used to override the MLTK Python package dependencies.

This should contain a list of install requirements delimited by a pipe |, e.g.:

export MLTK_SETUP_PY_DEPS="tensorflow==2.4.4|numpy==1.19.5|tflite-support==0.2.0|tensorflow_probability==0.12.2|onnxruntime==1.9.0|typing-extensions==3.7.4"


The temporary directory used by the MLTK. If not defined, then this defaults to: $TEMP/<user name>/mltk