bitnami LAMP – why is mod_rewrite not working

Yes it is enabled by default but make sure your framework or app httpd-app.conf has AllowOverride set to All.

<directory "..."> 
 ... 
 AllowOverride All 
 ... 
</directory>

For Codeigniter, make sure your .htaccess is in the same dir as your root index.php.

RewriteEngine on
RewriteCond $1 !^(index.php|images|robots.txt)
RewriteRule ^(.*)$ /index.php/$1 [L]
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