This blog post is part 3 of 3 of a series which explains how you can achieve maximum performance for your OpenCart store with the help of NitroPack by iSenseLabs.

In part 1 and part 2 we talked about how to increase the following parameters, which are reported by PageSpeed Insights:

• Optimize images
• Leverage browser caching
• Enable compression
• Eliminate render-blocking JavaScript and CSS in above-the-fold content
• Reduce server response time
• Prioritize visible content

NitroPack is among the most feature-rich optimization engines for OpenCart. In this blog post we will cover how you can use NitroPack and other tools to increase your Google PageSpeed score.

We will cover the following topics:

• Minify JavaScript
• Minify CSS
• Minify HTML

As you can see, this blog post will cover the Minification feature of NitroPack. A piece of code is called “minified” when it is stripped off any unnecessary new lines, white spaces, developer comments, or other redundant information which is not required by the browser. NitroPack has a built-in feature, which allows you to minify your JavaScript, CSS and HTML code.

Note: The NitroPack Minify features work only for code, which is located on your server. If you are using code which is on another domain, NitroPack will not have access to it and it will not be able to minify it. You will recognize the local files by their domain name - it must match the domain name of your website:

Minify JavaScript

How to optimize: Navigate to Admin > Nitro > Settings > Minification

Enable the following options:

1. Use Minification > Enabled
2. JavaScript files > Minify JavaScript files > Yes
3. JavaScript files > Combine JavaScript files > Yes
4. (Optional) You can experiment with the rest of the options in the JavaScript files tab and see how they will affect your score.

Minify CSS

How to optimize: Navigate to Admin > Nitro > Settings > Minification

Enable the following options:

1. Use Minification > Enabled
2. CSS files > Minify CSS files > Yes
3. CSS files > Combine CSS files > Yes
4. (Optional) You can experiment with the rest of the options in the CSS files tab and see how they will affect your score.

Minify HTML

How to optimize: Navigate to Admin > Nitro > Settings > Minification

Enable the following options:

1. Use Minification > Enabled
2. HTML files > Minify HTML files > Yes
3. HTML files > Keep HTML comments > No (If your website appears broken after clicking Save, try to switch this option to Yes)

Final words

Congratulations! You have now nailed your Google PageSpeed score! If you wish to increase your score to the maximum possible value, we refer you to the “Further optimizations” section below. We welcome your questions or suggestions in the comments.

Further optimizations

While the options above will help you increase your PageSpeed score, there is the possibility that the Minifier will not be compatible with some parts of your website. The reason for this is that different developers have different coding styles - if the minifier cannot properly interpret the code, then this could lead to unexpected bugs.

For such cases an intervention by a specialist can help increase your PageSpeed score. iSenseLabs provides custom services to further improve the performance of your webstore theme and web server. 

Theme Performance Optimization

This optimization will reduce the load time from the moment you receive the first byte of the response to the moment you receive all of the page content. Basically, this service includes the maximum theme performance optimization, which is possible for your theme:

• Fixing the theme-native speed weaknesses
• Creating CSS sprites
• Deferred parsing of JavaScript
• Bottlenecks and unnecessary loops
• Static resources minification and compression
• General optimizations

Server Performance Optimization

This has to do with the First Byte load, which is actually store-specific. On a general level the Server Performance Optimization is like a detective work - we investigate the delays on your web server and OpenCart system. The goal is to improve the response time. As an example, sometimes the slow-down could be caused by a module, other times by slow I/O, etc.

Here is the summary of the Server Performance Optimization:

• Minimizing high server response time
• Profiling
• Installation/Configuration of server mods
• Analysis and removal of bottlenecks and unnecessary loops
• Code refactoring
• General Optimizations

If you are interested, feel free to contact us on sales@isenselabs.com