# unisonweb/unison

A friendly programming language from the future

Repository: https://github.com/unisonweb/unison
Canonical: https://ross.abutalabs.com/products/unison
Homepage: https://unison-lang.org
Language: Haskell
License: NOASSERTION
License Family: other
Topics: haskell, programming-language, unison, unison-language, hacktoberfest
Last push: 2026-08-19T20:47:26+00:00

## Health v2 (maintenance only)
Score: 98/100 (v2, computed 2026-09-03T02:20:16.233290+00:00)
- activity 98, release rhythm 98, longevity 100
- inputs: {"age_days": 4137, "days_push": 14, "days_rel": 14, "gap_med": 19.0, "n_releases_24m": 31}
- 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 6717, forks 307 (observed 2026-08-28T04:09:48.030316+00:00)

## What it is
Unison is a statically-typed functional programming language with type inference, an effect (abilities) system, and content-addressed code stored as ASTs in a database. This repository contains the language implementation, including the UCM command-line codebase manager, compiler, and LSP server.

## Use cases
- learn a functional programming language with no builds
- eliminate dependency conflicts with hash-based code references
- build distributed systems with remote computation abilities
- get perfect incremental compilation and test caching
- do semantically-aware refactoring without merge conflicts
- store code as an AST database instead of text files

## When to choose
- you want a statically-typed functional language with effects and instant compilation
- you are building distributed applications, especially on Unison Cloud
- you are tired of build systems, encoders/decoders at boundaries, and name-based dependency conflicts
- you want to explore novel language design like content-addressed code

## When to avoid
- you need a mainstream language with a large ecosystem, libraries, and hiring pool
- your team relies on standard text-file version control workflows and existing tooling
- you need production battle-tested stability for a business-critical project today

## Facets
- artifact type: cli-tool
- maturity: active
- function: programming-language, compiler, interpreter, developer-tools, cli
- domain: programming-languages, developer-tools, microservices, compilers
- platform: windows, cli, cross-platform
- tags: unison-language, functional-programming, content-addressed-code, static-typing, effect-system, type-inference, codebase-manager, ucm, distributed-computing, linux, macos

## Member repositories
- unisonweb/unison (main) score 98

## Provenance
- Observed fields: from GitHub, fetched 2026-08-28T04:09:48.030316+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 2026-08-29T17:42:55.450817+00:00, confidence not recorded.
  - readme: https://github.com/unisonweb/unison (fetched 2026-08-28T04:09:48.030316+00:00, sha 4a6549ef6a81)
  - homepage: https://unison-lang.org (fetched 2026-08-29T08:39:09.687702+00:00, sha 5bb8a8ea01e1)
  - site_page: https://www.unison-lang.org/docs (fetched 2026-08-29T08:39:09.690497+00:00, sha 4cf281f49d9b)
  - site_page: https://www.unison-lang.org/docs/the-big-idea (fetched 2026-08-29T08:39:09.693091+00:00, sha 155e9fdf0346)
  - site_page: https://www.unison-lang.org/docs/tooling/ucm-desktop (fetched 2026-08-29T08:39:09.695764+00:00, sha 27f3aecd9890)
  - site_page: https://www.unison-lang.org/docs/fundamentals/abilities (fetched 2026-08-29T08:39:09.697779+00:00, sha 6c5de105fead)
  - site_page: https://www.unison-lang.org/docs/fundamentals/abilities/using-abilities-pt1 (fetched 2026-08-29T08:39:09.699858+00:00, sha 5981c681db6d)
  - site_page: https://www.unison-lang.org/docs/fundamentals/abilities/using-abilities-pt2 (fetched 2026-08-29T08:39:09.701757+00:00, sha cae7b5f21183)
  - site_page: https://www.unison-lang.org/docs/at-a-glance (fetched 2026-08-29T08:39:09.704119+00:00, sha 6a6e20482ec0)
- Data as of 2026-08-30T08:39:29.467469+00:00.