I came across a confusing and frustrating problem with Laravel that might catch a few people out. I have a single server running both the staging and production versions of the same Laravel-based website. Their .env files have the same APP_NAME – because they are the same application – and have the appropriate APP_ENV set.

Usefully Laravel prefixes cache, session data and redis keys, so they are unique per application you're using. That's nice. However, the problem here is that – by default – these prefixes only use the APP_NAME to make them unique.

You are able to override these prefixes with more .env keys (CACHE_PREFIX, REDIS_PREFIX, and SESSION_COOKIE), but how many people configure these? I think taking into account the APP_ENV might be a decent solution.

Currently, the prefixes are built like this;

Str::slug(env('APP_NAME', 'laravel'), '_').'_cache';

However, it would be nice if they looked like this;

Str::of(env('APP_NAME', 'laravel'))
	->append(env('APP_ENV', 'production'))
	->append(' cache')
	->slug('_')
	->value();

Takeaway: Make sure your APP_NAME is different for every application on your server else you might encounter unexpected conflicts.