# yesodweb/yesod

A RESTful Haskell web framework built on WAI.

Repository: https://github.com/yesodweb/yesod
Canonical: https://ross.abutalabs.com/products/yesod
Homepage: http://www.yesodweb.com/
Language: Haskell
License: MIT
License Family: permissive
Last push: 2026-07-29T15:57:04+00:00

## Health v2 (maintenance only)
Score: 75/100 (v2, computed 2026-09-03T02:20:16.233290+00:00)
- activity 95, release rhythm 35, longevity 100
- inputs: {"age_days": 6276, "days_push": 35, "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 2723, forks 385 (observed 2026-08-28T04:07:15.668064+00:00)

## What it is
Yesod is a type-safe, RESTful web framework for Haskell built on the WAI interface, featuring compile-time-checked routing, templating, and persistence DSLs. It emphasizes turning runtime bugs into compile-time errors while delivering high performance through compiled code and asynchronous IO.

## Use cases
- build a type-safe RESTful web API in Haskell
- develop a high-performance web application with compile-time route checking
- create a web app with safe HTML templating and form handling
- build a database-backed website with compile-time-checked persistence
- serve a web application with constant-memory, asynchronous IO

## When to choose
- you want maximum type safety and compile-time guarantees in web development
- you need high performance compiled web applications in Haskell
- you value DSLs for routing, templating, and persistence that are checked at compile time

## When to avoid
- your team does not know Haskell or wants a shallow learning curve
- you need a large ecosystem of off-the-shelf plugins and libraries
- you prefer dynamic or scripting languages for rapid prototyping

## Facets
- artifact type: framework
- maturity: active
- function: web-framework, routing, templating, orm, form-handling, http-server
- domain: web-development, backend, apis
- platform: cross-platform
- tags: type-safe, restful, wai, compile-time-checks, haskell, web-server

## Member repositories
- yesodweb/yesod (main) score 75

## Provenance
- Observed fields: from GitHub, fetched 2026-08-28T04:07:15.668064+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 2026-08-30T02:14:57.195711+00:00, confidence not recorded.
  - readme: https://github.com/yesodweb/yesod (fetched 2026-08-28T04:07:15.668064+00:00, sha a4d576fd87e2)
  - homepage: http://www.yesodweb.com/ (fetched 2026-08-29T09:58:03.752650+00:00, sha f2340084c9bf)
  - site_page: https://www.yesodweb.com/page/quickstart (fetched 2026-08-29T09:58:03.756626+00:00, sha 65271d42734f)
- Data as of 2026-08-30T08:39:29.467469+00:00.