WebContainer Slow Startup - App Takes Time to Boot
Your Bolt WebContainer takes a long time to start - 30+ seconds before seeing the dev server running. Development workflow is slow due to startup delays.
This happens consistently, making every new session wait.
Error Messages You Might See
Common Causes
- Large node_modules size slowing file system
- Many dependencies causing npm install to take forever
- Post-install scripts (build, setup) in package.json taking time
- WebContainer downloading dependencies on first run
- Heavy TypeScript compilation on startup
How to Fix It
Minimize dependencies: remove unused packages, audit with npm ls
Use npm ci instead of npm install for faster, deterministic installs
Remove unnecessary postinstall scripts or make them optional
Pre-compile TypeScript if possible, or disable strict mode in dev
Clear npm cache in Bolt: might be cached from previous run
Consider using pnpm instead of npm (faster for monorepos)
Real developers can help you.
You don't need to be technical. Just describe what's wrong and a verified developer will handle the rest.
Get HelpFrequently Asked Questions
Why is WebContainer slow on first run?
Downloading node_modules, dependencies, and setting up environment. Subsequent runs are cached
Should I commit node_modules?
No, Bolt installs fresh. Keep package-lock.json committed for reproducible builds
How do I speed up dependencies?
Use pnpm (faster), audit and remove unused packages, use npm ci instead of install