carry-on

Born to route. Forged in localhost.

A reverse proxy dev server that forwards your requests with the fury of a thousand metal warriors. Kills CORS errors dead. Also supports WebSockets.

For local development only. carry-on is a dev tool — it injects permissive CORS headers on everything and is not hardened for production use.

Install

go install github.com/amireldor/carry-on@latest

Or grab a binary from releases.

Usage

carry-on "/api@5000" 5713

Listens on :1987. Routes /api/* to localhost:5000 (stripping the prefix). Everything else goes to localhost:5713.

carry-on  ▶  :1987
  /api           →  localhost:5000  (strip)
  *              →  localhost:5713  (fallback)

Override the listening port with PORT:

PORT=8080 carry-on "/api@5000" 5713

Multiple routes:

carry-on "/api@5000" "/ws@5001" 5713

Keep the prefix instead of stripping it:

carry-on --no-strip "/api@5000" 5713

Config file

carry-on init        # generates carry-on.toml in the current directory
carry-on             # auto-loads carry-on.toml if present
carry-on -c proxy.toml

# carry-on.toml
# port = 1987

fallback = "localhost:3000"

[[route]]
path = "/api"
target = "localhost:8080"
# strip = true

[[route]]
path = "/ws"
target = "localhost:8081"
strip = false

CLI args take precedence over the config file. PORT env always wins.

CORS

carry-on injects CORS headers on every response by default — that's the whole point. No configuration needed. To disable:

carry-on --no-cors "/api@5000" 5713

Or in carry-on.toml:

cors = false

WebSockets

They just work. carry-on tunnels WebSocket upgrades transparently to the target, stripping prefixes as configured.

Flags

Flag	Description
--no-cors	Disable CORS header injection
--no-strip	Don't strip path prefix when forwarding (CLI routes only)
-c, --config	Path to config file

Route syntax

/path@target

target can be a port number (5000), a host:port (localhost:5000), or a full URL (http://localhost:5000).