dev-serve

name	dev-serve
description	Start and manage tmux-backed dev servers exposed through Caddy at wildcard subdomains.

dev-serve — One-Command Dev Server Hosting

Start a dev server in a tmux session and expose it via Caddy at <project>.YOUR_DOMAIN. One command up, one command down.

Setup

1. Install the script:

   cp scripts/dev-serve.sh ~/.local/bin/dev-serve
   chmod +x ~/.local/bin/dev-serve
   

2. Set your domain (one of):

   • Export DEV_SERVE_DOMAIN in your shell profile
   • Or edit the DOMAIN variable in the script

3. Requirements:

   • Caddy running with wildcard DNS + TLS (see caddy skill)
   • tmux, jq, curl
   • Caddy admin API on localhost:2019

CLI

dev-serve up <repo-path> [port]      # Start dev server + add Caddy route
dev-serve down <name>                # Stop dev server + remove Caddy route
dev-serve ls                         # List active dev servers
dev-serve restart <name>             # Restart dev server (keep Caddy route)

How It Works

1. Derives subdomain from the repo folder name (~/projects/myapp → myapp.YOUR_DOMAIN)
2. Detects the dev command from package.json scripts.dev (supports vite, next, nuxt, sveltekit)
3. Auto-patches Vite allowedHosts if a vite config file exists
4. Starts the dev server in a tmux session named dev-<name> with --host 0.0.0.0 --port <port>
5. Adds a Caddy route + dashboard link to the Caddyfile
6. Reloads Caddy via admin API (no sudo, no restart)
7. Verifies end-to-end: waits for the dev server to listen, then polls HTTPS until 2xx/3xx (up to 90s)

Examples

# Start with auto-assigned port (starts at 5200, skips used ports)
dev-serve up ~/projects/myapp
# → https://myapp.YOUR_DOMAIN

# Explicit port
dev-serve up ~/projects/myapp 5200

# Override dev command
DEV_CMD="bun dev" dev-serve up ~/projects/myapp 5300

# Stop and clean up
dev-serve down myapp

# List what's running
dev-serve ls

Configuration

Variable	Default	Description
DEV_SERVE_DOMAIN	(must be set)	Your wildcard domain (e.g. mini.example.com)
DEV_SERVE_STATE_DIR	~/.config/dev-serve	Where state JSON is stored
CADDYFILE	~/.config/caddy/Caddyfile	Path to your Caddyfile
CADDY_ADMIN	http://localhost:2019	Caddy admin API address
DEV_CMD	(auto-detected)	Override the dev server command

Port Convention

• Permanent services: 3100 range (managed in Caddyfile directly)
• Dev servers: 5200+ (managed by dev-serve, auto-assigned)

Vite allowedHosts

Vite blocks requests from unrecognized hostnames. dev-serve up automatically patches vite.config.ts (or .js/.mts/.mjs) to add the subdomain. If auto-patching fails, it prints the manual fix.

Architecture

Browser (Tailscale / LAN / etc.)
  → DNS: *.YOUR_DOMAIN → your server IP
    → Caddy (HTTPS with auto certs)
      → reverse_proxy localhost:<port>
        → Dev server (in tmux session)

Companion Skills

• caddy — Required. Sets up the Caddy reverse proxy with wildcard TLS.

Troubleshooting

Dev server not starting:

tmux attach -t dev-<name>    # see what happened

Cert not provisioning (curl exit 35): Wait 30-60s for DNS-01 challenge. Check tail -20 /var/log/caddy-error.log.

Caddy reload failed:

caddy reload --config ~/.config/caddy/Caddyfile --address localhost:2019

403 from Vite: The subdomain wasn't added to allowedHosts. Add it manually to your vite.config.ts:

server: { allowedHosts: ['myapp.YOUR_DOMAIN'] }