actix-website/content/docs/http2.md

title	menu	weight
HTTP/2	docs_protocols	250

Actix Web will prefer HTTP/2 connections if the client signals support for it via TLS ALPN.

Negotiation

When either of the rustls or openssl features are enabled, HttpServer provides the bind_rustls method and bind_openssl methods, respectively.

[dependencies]
actix-web = { version = "{{< actix-version "actix-web" >}}", features = ["openssl"] }
openssl = { version = "0.10", features = ["v110"] }

{{< include-example example="http2" file="main.rs" section="main" >}}

Upgrades to HTTP/2 described in RFC 7540 §3.2 are not supported. Starting HTTP/2 with prior knowledge is supported for both cleartext and TLS connections (RFC 7540 §3.4) (when using the lower level actix-http service builders).

Check out the TLS examples for concrete example.