Limits of CoffeeScript `--bare` flag for reducing bundle size in low‑traffic workloads

Goal

Assess whether compiling CoffeeScript with the `--bare` flag yields a meaningful size reduction for small modules that are served to low‑traffic users, while understanding any behavioral or tooling constraints that may arise.

Constraints and uncertainty

• The `--bare` flag removes the implicit IIFE wrapper, which can change the scoping of top‑level variables unless the code runs in strict mode or is manually wrapped.
• Certain CoffeeScript constructs such as class definitions or splat arguments may generate code that assumes the wrapper’s scope for correct hoisting.
• Source maps produced for `--bare` output have different line offsets, potentially causing mismatched debugging information if not adjusted.
• The actual byte‑size saving per module depends on the amount of boilerplate removed and the minification/gzip steps applied later in the build pipeline.

What is the typical reduction in transferred bytes for a minimal CoffeeScript file when compiled with `--bare`? Does the absence of the wrapper affect the runtime behavior of class definitions or splat arguments in the generated JavaScript? How should source‑map configuration be adapted to preserve accurate line numbers when using `--bare`?