What is express-stackman?

When a web app crashes, the error page usually shows a stack trace, a list of files and line numbers where things went wrong. But seeing "error at line 42 of app.js" isn't always helpful if you can't remember what's actually on that line. express-stackman fixes this by pulling in the actual source code around each line mentioned in the stack trace, so you can see exactly what your code was doing when it broke. It's designed for Express, a popular Node.js web framework. You add it to your app as a piece of middleware, essentially a plugin that sits between your routes and the outside world, and it kicks in only when an error occurs. Instead of a bare stack trace, you get an error page that shows the relevant lines of code surrounding each point in the call stack. By default it grabs seven lines of context on either side of the offending line, and you can adjust that number if you want more or less. This is a tool for developers working on Express apps, especially during local development. If you're iterating quickly, throwing test errors, and trying to track down bugs, seeing the code inline saves you from flipping back to your editor to check what a line actually says. The README notes it should only be used in development mode, not production, which makes sense since you don't want to expose source code to end users. One notable thing is its simplicity: it's a thin wrapper around another project called stackman, which does the actual work of extracting source code from stack frames. This project just makes it easy to drop that functionality into an Express app with minimal setup. It's a small, focused tool, it does one thing and doesn't try to be a full error-logging or monitoring solution.