One script tag. Every change reversible.
The Proa Runtime is the part of Proa your store actually runs: a single lightweight script that ships variants, runs experiments, and measures results. Here is what it does for your store, and the guarantees it makes.
<script src="https://runtime.tryproa.com/v1/s/<siteKey>.js"></script>The installation, simplified — copy the real snippet from Site settings (on Shopify it carries a few extra attributes that enable template tests). It goes in your theme's head once; everything after that happens from the dashboard. Step by step in the install guide.
What happens on a page view
The script loads
One small tag in your theme fetches your store's published configuration from a CDN close to the visitor.
Targeting decides
Which page, which audience, which experiment variant. Pages with nothing to change are left completely untouched.
The change applies
The winning version is in place before the visitor sees the page, so there is nothing to flash or jump.
The page is always safe
If our script is slow, blocked, or down, the page shows itself as if Proa were not there. Guaranteed, by construction.
the whole install; changes never need theme deploys again
compressed script, delivered from a CDN near your visitor
for a publish, a rollback, or a kill switch to reach visitors
third-party tracking cookies, in any mode, ever
The questions a careful operator asks
No flicker
Changes can apply before the page paints, so visitors never see the original content flash and switch. And if anything ever fails to load, the page simply shows itself: your store is never held hostage by our script.
No speed hit
The script is about 4 KB compressed and served from a CDN close to your visitor. If you would rather keep it off the rendering path entirely, run it async and it costs the page nothing.
No theme deploys
The tag goes into your theme once. After that, every publish, experiment, and rollback happens from the dashboard: no theme edits, no app blocks, no maintenance window, no code review queue on your side.
Reversible, always
Every publish keeps a permanent point of return. Rolling back, or turning everything off, is one click and reaches your visitors in under a minute.
Contained by design
The Runtime only runs on the domains you authorize, and visitors receive exactly the version you approved and published, nothing else.
Private by default
We measure how versions perform, not who your visitors are. No third-party tracking cookies, and customer names, emails, phones, and addresses are never read.
One tradeoff, stated honestly
Any tool in this category faces the same physics: guaranteeing zero flicker means doing a little work before the page paints; staying entirely off the rendering path means the original content can show for an instant before it changes. Proa lets you choose per store, switching is trivial, and we will tell you which mode fits what you are testing.
Tools that promise zero flicker and zero cost at the same time are hiding one of the two.
What we measure, and what we never touch
What we measure
- How pages and variants perform: views, exposures, and orders
- Revenue per variant, attributed through your store's own purchase flow
- Each currency reported separately, so unlike money never sums into one number
Never touched
- Customer personal data: names, emails, phones, and addresses are never read
- Third-party tracking cookies: the script sets none, in any mode
- Anything to sell: measurement exists to answer your questions, and the data is yours
Measurement is an explicit opt-in, off by default. Previewing a variant affects only your own browser tab and counts nothing.
Want to see it running on your store?
A demo takes the same path described above: your theme, your products, a preview link only you can see.
Book a demo