Why Hayashi?
Applied econometrics has been dominated by proprietary tools for decades. They are powerful, but they are expensive, closed, and difficult to extend. Hayashi exists to give economists, researchers, and students a modern, open alternative without sacrificing performance.
It is built in Rust, uses a familiar Stata-like syntax, and adds modern language features: pipes, closures, namespaces, match expressions, and a plugin system.
Name and inspiration
The project is named after Fumio Hayashi, author of Econometrics, one of the most influential graduate textbooks in the field. The language aims to honor that tradition: rigorous, practical, and focused on empirical work.
Architecture
Hayashi is composed of two main projects:
- Hayashi — the interpreter, REPL, CLI, and runtime.
- Greeners — the Rust econometrics and dataframe library that powers the estimators.
This split keeps the core language lean while allowing Greeners to be reused by other Rust projects or bindings.
Licensing
| Component | License |
|---|---|
| Hayashi language implementation | GPL-3.0-only |
| Greeners library | MIT |
| Books and documentation | CC BY-SA 4.0 |
Roadmap
Hayashi is under active development. The path to 1.0.0 focuses on:
- Stabilizing the core language and runtime.
- Expanding the validation suite to cover the main estimator families.
- Growing the plugin ecosystem with real external packages.
- Building developer tools: LSP, formatter, and debugger.
- Publishing comprehensive documentation and books.
Team
Hayashi is maintained by Flávio de Vasconcellos Corrêa, with contributions from the open-source community.
If you use Hayashi in research, please cite the release version and the project URL.