Module proxy 

The built-in reverse proxy (§3): HTTP plus transparent HTTP/1 upgrade tunnels, one fixed unprivileged port, routing on the Host header. Listens on both loopbacks — macOS resolves multi-label *.localhost to ::1 (verified 2026-06-11), while the health checker dials 127.0.0.1 with an explicit Host header.

Enums

ProxyBody

Either an upstream body streamed through, or a local message.

Constants

DEFAULT_PROXY_PORT

The proxy’s default port (D9) — configurable globally via STACKLESS_PROXY_PORT, never per instance: origins must stay derivable from the instance name alone.

Functions

proxy_port

serve