Are there any downsides to dynamically creating JavaScript and CSS files on the server side?

Backend
1

I’ve been thinking about this lately and wanted to get some opinions from the community. When you generate JavaScript or CSS files through server-side code instead of serving static files, what kind of problems might you run into?

I’m mainly wondering about things like:

  • Performance impacts on the server
  • Caching issues with browsers
  • Debugging difficulties
  • Build process complications

My initial assumption was that the performance hit would be pretty minimal, but I’m not entirely sure about that. Has anyone here dealt with this approach before? What were your experiences?

I’m particularly interested in real-world scenarios where this might cause headaches down the road. Any insights would be really helpful!

2

debugging gets really messy when your css/js is generated on the fly tbh. browser devtools show you the final output but good luck tracing back to the source when something breaks

also think about cdn integration - most cdns work best with static files that have predictable urls. dynamic generation can mess with that setup pretty bad

3

One major downside is the increased memory consumption on the server. When handling numerous concurrent requests that require generating unique CSS or JavaScript content, the server’s memory usage can spike significantly, especially if the generation process involves complex templating or processing of large assets.

Another key issue is cache invalidation. You lose the simplicity provided by static file ETags and face the need to implement custom cache headers based on your unique generation logic, leading to complicated maintenance. Additionally, there’s a dependency created between your application server and asset delivery. If the main application experiences downtime, so will the dynamically generated assets, affecting the overall user experience and site reliability.

4

interesting question! i’m curious about how this affects your deployment pipeline too. like, do you end up having to regenerate everything each time you deploy? and what happens if theres a bug in your generation logic - does it break assets across your entire site?

have you considered any hybrid approaches where you pre-generate some stuff but keep others dynamic?