fallow vs tach
JavaScript and TypeScript analysis compared with Python boundary enforcement
fallow analyzes JavaScript and TypeScript codebases for maintainability, unused code, duplication, styling, and architecture issues. tach enforces declared module dependencies and public interfaces in Python projects, with a narrower focus on architectural boundaries.
fallow: Analyze TypeScript and JavaScript Codebases
fallow builds a repository graph to find code health issues, complexity hotspots, duplication, architecture violations, styling drift, and unused code. Use it from the CLI, CI, editors, or coding agents, with findings scoped to changed files.
tach: Enforce Python Module Dependencies
Tach checks Python imports against declared module dependencies and interfaces, helping teams prevent unwanted coupling and dependency cycles. It is actively maintained and suits projects adopting modular architecture incrementally.
| fallow | tach | |
|---|---|---|
| Language | Rust | Rust |
| License | MIT | MIT |
| Stars | 5k | 2.8k |
| Forks | 170 | 94 |
| Last analyzed | Oct 7, 2026 | Oct 8, 2026 |
Key differences
- fallow covers JavaScript and TypeScript code health, duplication, unused code, and styling; tach focuses on Python module dependencies and interfaces.
- fallow builds a repository graph and supports CLI, CI, editor, and coding-agent workflows; tach is a command-line tool that integrates with CI/CD and pre-commit hooks.
- fallow can audit changed files and exclude inherited findings from pull-request gates; tach supports incremental adoption by allowing unchecked modules and deprecated dependencies.
- Both are written in Rust and use the MIT license, but fallow documents Node.js 22.12.0 or later and Rust 1.96 requirements, while tach requires Python 3.10 or newer and a Rust component.
- fallow's contributions are concentrated among one person; tach's contributions are not concentrated in one person, though its issue closure has been slower than pull request merging.
Choose fallow if you…
- need broad static analysis for JavaScript or TypeScript codebases, including duplication, unused code, and styling drift.
- want pull-request findings scoped to changed files and tools for CLI, CI, editors, or coding agents.
- need optional type-aware analysis, runtime-coverage integration, or security checks.
Choose tach if you…
- need to enforce declared import dependencies and public interfaces in Python modules.
- want to introduce architecture boundaries incrementally, including for selected modules.
- need dependency visualization, layered rules, or reports of module dependencies and usages.
This comparison is generated with AI from the OSRepos analyses of both projects. Always check each project's repository and documentation before choosing.