* I've worked on JS for x years.
* I've written client-side JS for x companies.
Anyway, you get the idea.
The HN effect only lasts for so long. Once the flash crowd evaporates, prospects need more than such an unvarnished offer before they can act.
Cozy up to your prospects. Release some educational content. Give some examples of how you deliver value with your code reviews.
Going forward, a testimonial strategy definitely wouldn't hurt.
Like very well documented and widely used compiler of some language to JavaScript, perhaps?
Do you know if it would hurt those sales in any way if he inserts a short bio for those who don't?
* I've worked on JS for x years.
* I've written client-side JS for x companies.
Anyway, you get the idea.