In my opinion, programmers have a very high impact. While salespeople help sell the product, the programming you put into the product is what creates the actual impact.

Something you could do is contact the customers and ask them for numbers. They will most likely know what kind of impact the website or app you helped develop made. You can then use these numbers in your CV.

Another thing I often see people forget: let your uniqueness shine. Include a catchy phrase, a quote or something else personal as the first thing on your CV. This will certainly spice up your CV and make it less boring.