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Overview

What is tach?

Tach allows you to control dependencies between your Python modules. Modules can also define an explicit public interface to prevent deep coupling.

This creates 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 is a CLI tool, 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.
  • tach check - Check that boundaries are respected.
  • tach sync - Sync constraints with the actual dependencies in your project.
  • tach show - Visualize your project's dependency graph.
  • tach report - Generate a dependency report for a file or module.
  • tach test - Run only the tests impacted by your changes
  • tach install - Install Tach into your development workflow (e.g. pre-commit)