HTTP/3

HTTP/3 rides Cloudflare libquiche over UDP via a small JNI shim (native/enso_quiche/enso_quiche.c). Pure-Java QPACK + H3 framing on top of quiche's transport primitives. Same Ring handler contract as h1/h2 — :protocol becomes "HTTP/3.0".

From a release jar (zero libquiche install)

Every release publishes core, per-classifier, and fat jars to Clojars. Three consumption patterns.

Core only, no h3 (~200 KB)

{:deps {com.s-exp/enso {:mvn/version "1.0.0-alphaN"}}}

Per-platform classifier (~3.5 MB)

Add core plus the classifier matching your deploy target. tools.deps resolves the classifier artifact via the $<classifier> coord suffix.

{:deps {com.s-exp/enso                 {:mvn/version "1.0.0-alphaN"}
        com.s-exp/enso$darwin-arm64    {:mvn/version "1.0.0-alphaN"}}}

Available classifiers:

• darwin-arm64
• linux-amd64, linux-arm64
• linux-musl-amd64, linux-musl-arm64

Alpine/musl variants selected automatically at runtime when /lib/ld-musl-*.so.1 is present; falls back to glibc shim otherwise.

For multi-platform uber-jars, declare multiple classifier deps side by side:

{:deps {com.s-exp/enso                    {:mvn/version "1.0.0-alphaN"}
        com.s-exp/enso$darwin-arm64       {:mvn/version "1.0.0-alphaN"}
        com.s-exp/enso$linux-amd64        {:mvn/version "1.0.0-alphaN"}
        com.s-exp/enso$linux-musl-amd64   {:mvn/version "1.0.0-alphaN"}}}

Quiche.java picks the matching shim from the classpath at load time.

Enabling h3

(enso/run-server handler
  {:port 8443
   :ssl-context ctx                 ;; for h1/h2 on the TCP port
   :http2 true
   :http3 true
   :http3-cert-path "/path/cert.pem"
   :http3-key-path  "/path/key.pem"})

• Uses its own UDP socket; can co-exist with h1/h2 on the same port number.
• Alt-Svc auto-advertised on h1/h2 responses when h3 enabled.
• See options.md for full knob list.

Dev build (dynamic-link against system libquiche)

brew install cloudflare-quiche              # macOS
make -C native/enso_quiche                  # → target/native/<os>-<arch>/libenso_quiche.<ext>
clojure -T:build javac-bench                # optional: Netty+Jetty bench servers

Release / distributable build

Static-link libquiche 0.29.3 into the shim so the resulting .dylib/.so has no runtime dep on system libquiche. Release CI (.github/workflows/release.yml) does this across five platforms and packages every shim into the fat jar.

To reproduce locally:

git clone --depth 1 --branch 0.29.3 https://github.com/cloudflare/quiche.git /tmp/quiche
(cd /tmp/quiche && cargo build --release --lib --features ffi,pkg-config-meta)
make -C native/enso_quiche QUICHE_STATIC=1 \
     QUICHE_INCLUDE_DIR=/tmp/quiche/quiche/include \
     QUICHE_LIB_DIR=/tmp/quiche/target/release

The built shim is bundled at META-INF/native/<os>-<arch>/. At load time Quiche.java extracts the shim into a per-JVM temp directory (unique random name — safe for multi-JVM hosts) then System.loads it.

Platform classifier resolution

• macOS → darwin-arm64 (Apple Silicon only; Intel Macs need a dev/dynamic build via make -C native/enso_quiche)
• Linux glibc → linux-arm64 / linux-amd64
• Linux musl (Alpine, Wolfi, Chimera) → linux-musl-*, fallback to linux-* if musl-built shim absent. Detection: /lib/ld-musl-*.so.1.

Override for local dev: -Denso.quiche.shim=/abs/path/to/libenso_quiche.dylib.

Notes on the JNI vs FFM choice

FFM path tried but hit a JDK 25 libmalloc corruption bug on macOS ARM64 (matches what Netty steers around in CleanerJava25.java). JNI migration eliminated it.