# zesterer/tao

A statically-typed functional language with generics, typeclasses, sum types, pattern-matching, first-class functions, currying, algebraic effects, associated types, good diagnostics, etc.

Repository: https://github.com/zesterer/tao
Canonical: https://ross.abutalabs.com/products/zesterer-tao
Homepage: https://tao.jsbarretto.com/
Language: Rust
License: MPL-2.0
License Family: copyleft
Topics: functional, programming-language, compiler
Last push: 2025-03-23T21:36:31+00:00

## Health v2 (maintenance only)
Score: 38/100 (v2, computed 2026-09-03T02:20:16.233290+00:00)
- activity 12, release rhythm 35, longevity 100
- inputs: {"age_days": 2429, "days_push": 528, "days_rel": null, "gap_med": null, "n_releases_24m": 0}
- flags: no_releases
- formula: round(0.45*activity + 0.35*rhythm + 0.20*longevity); archived -> min(score, 10)

## Adoption (not part of the score)
Stars 1161, forks 22 (observed 2026-08-28T04:03:49.246438+00:00)

## What it is
Tao is a statically-typed functional programming language implemented in Rust, featuring generics, typeclasses, sum types, pattern matching, first-class functions, currying, and generalised algebraic effects. It is a hobby/experimental language focused on totality and extreme optimisation, with a compiler and an in-browser playground.

## Use cases
- experiment with algebraic effects in a functional language
- learn typeclasses and sum types through a small language
- try a statically-typed functional language in the browser
- study compiler design and MIR optimisation techniques
- write total programs that explicitly handle all inputs
- explore parser combinators in a functional language

## When to choose
- you want to experiment with cutting-edge functional language features like algebraic effects and totality
- you are researching type systems or compiler optimisation
- you want a small, readable codebase for learning how languages are implemented

## When to avoid
- you need a production-ready language with ecosystem, libraries, and long-term support
- you need guaranteed stability or backwards compatibility
- you prefer imperative or object-oriented programming styles

## Facets
- artifact type: cli-tool
- maturity: experimental
- function: compiler, interpreter, programming-language, type-system, parser
- domain: programming-languages, compilers
- platform: cross-platform, rust, browser, cli
- tags: functional-language, algebraic-effects, typeclasses, sum-types, pattern-matching, totality, hobby-language, diagnostics, functional

## Member repositories
- zesterer/tao (main) score 38

## Provenance
- Observed fields: from GitHub, fetched 2026-08-28T04:03:49.246438+00:00.
- Health v2: computed from the inputs above; adoption is never an input.
- Inferred fields (summary, facets, guidance): AI-extracted, prompt v1, taxonomy v1, on 2026-08-30T08:22:58.041647+00:00, confidence not recorded.
  - readme: https://github.com/zesterer/tao (fetched 2026-08-28T04:03:49.246438+00:00, sha b0a9d03f08be)
  - homepage: https://tao.jsbarretto.com/ (fetched 2026-08-29T12:36:14.515173+00:00, sha cf55989e3ab4)
- Data as of 2026-08-30T08:39:29.467469+00:00.