Skip to content

Overview

What is tach?

tach allows you to define boundaries and control dependencies between your Python modules. Modules can also define an explicit public interface through __all__ to prevent deep coupling.

This enforces a decoupled, modular architecture, which makes maintenance and development easier.

If a module tries to import from another module that is not listed as a dependency, tach will report an error.

When a module is in 'strict mode', if another module tries to import from it without using its public interface, tach will report an error.

tach runs on the CLI, and is ideal for pre-commit hooks and CI checks.

Tach is:

  • 🌎 Open source
  • 🐍 Installable via pip
  • 🔧 Able to be adopted incrementally
  • ⚡ Implemented with no runtime impact
  • ♾️ Interoperable with your existing systems (cli, hooks, ci, etc.)

Commands

  • tach mod - Interactively define module boundaries in your Python project.
  • tach check - Check that boundaries are respected.
  • tach sync - Sync constraints with actual dependencies in your Python project.
  • tach report - Generate a dependency report for a file or module in your Python project.
  • tach install - Install tach into your development workflow (e.g. pre-commit)
  • tach clean - Delete all existing configuration and start from a clean slate.