Separate environments for Frontend and Backend

When developing for frontend locally, I used to access the frontend per app_dev.php, and backend as normal (in prod environment), because backend is significantly slower in dev environment.
Is it possible to do it using .env file in C4.8? Backend in dev mode really slows the work down...

Ok, I dig little bit into the code, it looks like ContaoKernel checks the $_SERVER['APP_ENV'] variable, before reading it from the .env file, so I had the idea to set the APP_ENV to 'prod', if the URI_STRING begins with contao/, but I can't get it to work. May be someone can help with this?

I'm using this in my .htaccess:

Code:

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RewriteRule ^contao - [E=APP_ENV:prod]

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Quick solution:

Code:

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# /web/.htaccess

RewriteCond %{ENV:REDIRECT_APP_ENV} (.+)
RewriteRule .* - [ENV=APP_ENV:%1]
RewriteRule ^contao - [ENV=APP_ENV:prod]

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