wt

Deterministic port assignment and HTTP proxy switcher for dev worktrees.

Assign every project directory a stable port (4000-5999) based on its path, and optionally run a reverse proxy on :3000 that can instantly switch between targets — no HMR reconnect issues.

Installation

npm install -g @michalicat/trop

This installs the wt command globally.

Commands

| Command | Description | |---|---| | wt port [target] | Print the deterministic port for a target (alias or path, default: current git root/cwd) | | wt id [target] | Print the stable ID (resolved real path) used for hashing | | wt alias <name> <value> | Create an alias. Value can be a path or id:YOUR_ID | | wt aliases | List all aliases | | wt use <target> | Set the active target (switches proxy instantly if running) | | wt status | Show the current active mapping (live info if proxy is running) | | wt start | Start the reverse proxy on :3000 with WebSocket/HMR support |

How it works

1. Deterministic ports — Each directory gets a stable port via SHA-1(realpath) mod 2000 + 4000. The same folder always maps to the same port, so you can hardcode it in your dev server config.

2. Reverse proxy on :3000 — wt start launches an HTTP/WebSocket reverse proxy on port 3000. It forwards all traffic to whichever target is currently active.

3. Instant switching — wt use <target> switches the proxy target immediately (via a control API on port 3010). No restart, no reconnect — HMR connections stay alive.

4. Aliases — Name your worktrees (wt alias app ./worktrees/app) so you can switch with wt use app instead of typing paths.