Livery

One handler set. Every version of HTTP.

Website · Docs · Design

---

Livery is a BEAM-native web framework that serves the same router and middleware over HTTP/1.1, HTTP/2, and HTTP/3 from a single runtime. WebSocket, WebTransport, Server-Sent Events, OpenAPI, MCP, and OpenTelemetry-style observability are built-in modules. It is written in the spirit of Axum + Tower + Hyper, on Erlang/OTP.

Router = livery_router:compile([
    {<<"GET">>, <<"/">>, fun(_Req) ->
        livery_resp:text(200, <<"hello from livery">>)
    end},
    {<<"GET">>, <<"/users/:id">>, {users, show}}
]),

livery:start_service(#{
    http  => #{port => 80, redirect => https},
    https => #{port => 443, cert => Cert, key => Key, alpn => [h2, http1]},
    http3 => #{port => 443, cert => Cert, key => Key},
    router => Router,
    middleware => [{livery_request_id, undefined}, {livery_access_log, #{}}],
    alt_svc => advertise
}).

Install

%% rebar.config
{deps, [{livery, {git, "https://github.com/benoitc/livery.git", {branch, "main"}}}]}.

Features

• One handler, three wires — write a handler once; serve it over H1, H2, and H3 with shared routing, middleware, and Alt-Svc upgrade.
• Tower-style middleware — value-based call(Req, Next, State) pipelines, composable per service or per route.
• Streaming — chunked, SSE, NDJSON, WebSocket and WebTransport over H2/H3, and file responses with byte ranges.
• OpenAPI — generate a 3.1 document from routes, serve Redoc or Swagger UI, and validate request bodies against a JSON-Schema subset.
• MCP — serve the Model Context Protocol Streamable HTTP transport on the main listener.
• Observability & auth — OpenTelemetry-style traces/metrics, trace-correlated logs, JWT/JWKS/OIDC, signed sessions, introspection.

Documentation

Full guides, tutorials, and the generated API reference live at https://benoitc.github.io/livery/. For contributors, see AGENTS.md.

License

Apache-2.0.