We just developed our website with Magento 2.1.8 but it takes time to load.
Can someone please tell where is the lag?
This steps is useful for improve page speed-up.
I hope this will useful for you.
Install and configure Varnish, it has massive impact on performance of the store.
Varnish Cache is an open source web application accelerator (also referred to as an HTTP accelerator or caching HTTP reverse proxy). Varnish stores (or caches) files or fragments of files in memory; this enables Varnish to reduce the response time and network bandwidth consumption on future, equivalent requests. Unlike web servers like Apache and nginx, Varnish was designed for use exclusively with the HTTP protocol.
Follow this link for more information: https://devdocs.magento.com/guides/v2.0/config-guide/varnish/config-varnish.html
Also, make sure that cache are always Enabled in production environment.