My Ghost blog, NGiNX pagespeed config for specific "location"'s.

proxy_pagespeed.conf

pagespeed RewriteLevel PassThrough;
pagespeed PreserveUrlRelativity on;
pagespeed NoTransformOptimizedImages on;

pagespeed EnableFilters rewrite_images,recompress_images,insert_image_dimensions;
pagespeed EnableFilters remove_comments,collapse_whitespace,extend_cache,convert_meta_tags;
pagespeed EnableFilters remove_quotes,insert_dns_prefetch;
pagespeed EnableFilters rewrite_css,fallback_rewrite_css_urls,rewrite_style_attributes,inline_css;
pagespeed EnableFilters rewrite_javascript;

pagespeed DisableFilters inline_images,combine_css,combine_javascript;