dev

name	dev
description	Watch mode development using Node --experimental-transform-types. No transpiler needed. Watches ./src/, restarts on changes. Custom entry files supported. Experimental command — may change. Use when running TypeScript in dev mode.
metadata	{"type":"core","library":"@bomb.sh/tools","library_version":"0.6.0","requires":["lifecycle"],"sources":["bombshell-dev/tools:src/commands/dev.ts"]}

Dev

Runs a TypeScript file with native Node TypeScript support and watches for changes.

Setup

pnpm run dev

How It Works

pnpm run dev runs bsh dev which shells out to:

node --experimental-transform-types --no-warnings --watch-path=./src/ <file>

• Default file: ./src/index.ts
• Watch path: ./src/ — restarts on any change in the source directory
• No transpiler needed — Node handles TypeScript natively via --experimental-transform-types

Custom Entry

pnpm run dev -- ./src/other.ts

Additional arguments after the file path are passed through to Node.

Note

This is an experimental command that relies on Node's --experimental-transform-types flag. Most Bombshell packages use a TDD loop (pnpm run test) as their primary development workflow rather than the dev server. The dev command is useful for running scripts or servers during development, not as the main iteration cycle.

Tension: Dev command stability vs experimental Node features. The underlying --experimental-transform-types flag may change behavior between Node versions. If you hit issues, fall back to the test-driven workflow.

Common Mistakes

CRITICAL: Using tsx or ts-node

Node handles TypeScript natively. External transpilers are unnecessary and add complexity.

# Wrong
npx tsx src/index.ts
npx tsx watch src/index.ts
npx ts-node src/index.ts
node -r ts-node/register src/index.ts

# Correct
pnpm run dev

HIGH: Installing TypeScript transpilers as dependencies

These packages are not needed in Bombshell projects.

// Wrong — package.json
{
  "devDependencies": {
    "tsx": "^4.0.0",
    "ts-node": "^10.0.0",
    "esbuild-register": "^3.0.0"
  }
}

// Correct — no transpiler dependencies needed
{
  "devDependencies": {
    "@bomb.sh/tools": "^0.3.1"
  }
}

See Also

• build/SKILL.md — Both handle TS compilation in different modes