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My development environment is not the fastest. I takes roughly 500ms per PHP request. It\'s starting to
Symfony documentation is always the first place where to start look: How to Use Assetic for Asset Management
In the prod environment, your JS and CSS files are represented by a single tag each. In other words, instead of seeing each JavaScript file you're including in your source, you'll likely just see something like this:
Moreover, that file does not actually exist, nor is it dynamically rendered by Symfony (as the asset files are in the dev environment). This is on purpose - letting Symfony generate these files dynamically in a production environment is just too slow.
Instead, each time you use your app in the prod environment (and therefore, each time you deploy), you should run the following task:
php app/console assetic:dump --env=prod --no-debug
This will physically generate and write each file that you need (e.g. /js/abcd123.js). If you update any of your assets, you'll need to run this again to regenerate the file.