# IoLanguage/io

Io programming language. Inspired by Self, Smalltalk and LISP.

Repository: https://github.com/IoLanguage/io
Canonical: https://ross.abutalabs.com/products/io
Homepage: http://iolanguage.org
Language: C
License: NOASSERTION
License Family: other
Last push: 2026-08-15T23:14:26+00:00

## Health v2 (maintenance only)
Score: 66/100 (v2, computed 2026-09-03T02:20:16.233290+00:00)
- activity 97, release rhythm 8, longevity 100
- inputs: {"age_days": 6767, "days_push": 18, "days_rel": null, "gap_med": null, "n_releases_24m": 0}
- flags: no_license
- formula: round(0.45*activity + 0.35*rhythm + 0.20*longevity); archived -> min(score, 10)

## Adoption (not part of the score)
Stars 2790, forks 310 (observed 2026-08-28T04:07:22.049742+00:00)

## What it is
Io is a small, dynamic prototype-based programming language implemented in C, inspired by Self, Smalltalk, Lisp, and Lua, where everything is a message send and concurrency is built on actors and futures. The VM now targets WebAssembly/WASI by default, running under wasmtime, Node.js, or in the browser with a REPL and an Io↔JavaScript bridge.

## Use cases
- learn prototype-based programming
- embed a small scripting language in a C application
- run a scripting language in the browser via WebAssembly
- experiment with actor and future-based concurrency
- build DSLs with runtime-inspectable message trees
- study minimal language design

## When to choose
- you want a tiny, conceptually unified language with minimal syntax
- you need runtime introspection and code-as-data (message trees)
- you want prototype-based objects with differential inheritance
- you want a language that runs in WASI hosts or the browser

## When to avoid
- you need a large ecosystem or standard library
- you need raw throughput for production workloads
- you need a well-tested, production-hardened WASM target (still early-access)
- your team requires mainstream tooling and hiring pool

## Facets
- artifact type: cli-tool
- maturity: active
- function: interpreter, programming-language, concurrency
- domain: programming-languages, compilers
- platform: wasm, browser, cross-platform, c
- tags: prototype-based, actors, futures, wasi, small-language, lisp-inspired, self-inspired, browser-repl, programming-language

## Member repositories
- IoLanguage/io (main) score 66

## Provenance
- Observed fields: from GitHub, fetched 2026-08-28T04:07:22.049742+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 2026-08-30T08:31:45.634122+00:00, confidence not recorded.
  - readme: https://github.com/IoLanguage/io (fetched 2026-08-28T04:07:22.049742+00:00, sha 8f02a5507e2c)
  - homepage: http://iolanguage.org (fetched 2026-08-29T09:55:06.492835+00:00, sha 0e7affe0f3b1)
  - site_page: https://iolanguage.org/docs/index.html (fetched 2026-08-29T09:55:06.495564+00:00, sha 8d27f47051e2)
  - site_page: https://iolanguage.org/FAQ/index.html (fetched 2026-08-29T09:55:06.497220+00:00, sha 21bc6ef7c327)
- Data as of 2026-08-30T08:39:29.467469+00:00.