<IfModule mod_rewrite.c>
RewriteEngine On
RewriteBase /api/

# /api/v1/users/register => /api/v1/users.php?__route=register
RewriteRule ^v1/([a-zA-Z0-9_]+)/?$ v1/$1.php [QSA,NC,L]
RewriteRule ^v1/([a-zA-Z0-9_]+)/(.*)$ v1/$1.php?__route=$2 [QSA,NC,L]
</IfModule>