reitit

Reitit

Reitit is a fast, data-driven router for Clojure and ClojureScript. Routes are plain data — vectors of [path route-data children*]. Every routing component (middleware, coercion, docs) reads from that data map.

Quick Decision: What do you need?

Task	Go to
Understand route syntax, router creation, path/name-based routing, route data, route conflicts	core-concepts.md
Ring handler, request-method routing, middleware, content negotiation, exception handling	ring.md
Coercing request params / response bodies with malli, spec, or schema	coercion.md
Generate OpenAPI 3 or Swagger 2 docs	openapi.md
Frontend/browser routing (ClojureScript, hash/HTML5 history, controllers)	frontend.md
Something isn't working / weird behavior / things to avoid	anti-patterns.md

Core Mental Model

Routes are pure data — a nested vector of [path ?data & children]. A router compiles that tree once at startup: it flattens paths, merges nested route data (via meta-merge), resolves conflicts, and selects the fastest matching algorithm. At request time, match-by-path or match-by-name returns a Match record containing :path-params, :data, and a compiled :result.

Ring layer (reitit-ring) extends the core router with request-method dispatch (:get, :post, …), :handler functions, and a :middleware chain that is compiled per-endpoint — middleware that declares :compile can inspect route data and return nil to skip itself entirely, yielding zero overhead for routes that don't need it.

Coercion is pluggable: attach a Coercion implementation (malli, spec, or schema) under :coercion in route data, declare :parameters / :responses schemas, then mount the coercion middleware. Coerced values arrive in request :parameters.

Modules

Artifact	Purpose
metosin/reitit	All bundled
metosin/reitit-core	Routing core only
metosin/reitit-ring	Ring router + middleware support
metosin/reitit-middleware	Common data-driven middleware (params, exceptions, muuntaja)
metosin/reitit-coercion	Coercion protocol
metosin/reitit-schema	Plumatic Schema coercion
metosin/reitit-spec	clojure.spec / data-specs coercion
metosin/reitit-malli (via reitit)	Malli coercion
metosin/reitit-swagger	Swagger 2 docs
fi.metosin/reitit-openapi	OpenAPI 3 docs
metosin/reitit-swagger-ui	Integrated Swagger UI
metosin/reitit-frontend	ClojureScript frontend routing
metosin/reitit-http	Pedestal-style interceptor routing
metosin/reitit-interceptors	Common interceptors for reitit-http