Native-Speed AJAX Signups (Ultra Ajax)
The signup form is the single most-touched part of any email plugin — every visitor who subscribes uses it. Super Speedy Emails makes that submission near-instant with a feature called Ultra Ajax: a small must-use plugin that handles the request before the full WordPress stack loads. This article explains what it does, how to confirm it’s running, and how to turn it off if you need to.
Table of Contents
What it does
Normally, a form submission to WordPress boots the entire stack — every active plugin, the theme, and the full REST framework — just to record one email address. That overhead adds up to noticeable lag on a busy site.
Ultra Ajax installs a must-use plugin (wp-content/mu-plugins/sse-fast-ajax.php) that loads before the normal plugin and theme stack. It watches for the two visitor-facing signup requests — subscribing, and updating subscription preferences — and handles them with a minimal WordPress load, skipping the rest of the boot. The result: the field clears and your success message appears with no perceptible delay.
Everything else (admin pages, other REST routes) falls through to normal WordPress untouched — the fast path only ever handles those two public actions, so there’s no effect on the rest of your site.
It’s automatic
Ultra Ajax is installed for you when you activate Super Speedy Emails, and it’s on by default. There’s nothing to configure to get the speed benefit — your forms are already using it.
Confirming it’s active
Two ways to check:
- Settings screen. Go to Super Speedy Emails → Settings → Advanced. The Ultra Ajax row shows Active (the mu-plugin is installed) or Not Installed.
- Direct check. Visit
https://yoursite.com/wp-json/sse/v1/subscribe?is_sse_ultra_ajax_active=1in a browser. If Ultra Ajax is running you’ll see a short confirmation message; if not, you’ll get the normal REST response.
If it shows “Not Installed”
The mu-plugin couldn’t be copied into place. Usually that means wp-content/mu-plugins/ isn’t writable, or doesn’t exist and couldn’t be created. To fix:
- Make sure
wp-content/mu-plugins/exists and is writable by WordPress. - Deactivate and reactivate Super Speedy Emails — installation runs on activation.
If your host blocks mu-plugins entirely, that’s fine: signups still work, just through the standard (slightly slower) path. Nothing breaks — you only lose the speed boost.
Turning it off
You normally wouldn’t, but if you need to disable the fast path (for debugging, or a conflict with another mu-plugin), set the sse_mu_enabled flag off in the sse_options option. With it off, the mu-plugin stays installed but immediately hands every request to normal WordPress. Signups continue working exactly as before, just without the fast path.
Does it change behaviour?
No. Ultra Ajax is purely a performance optimisation. The same validation, spam protection (Spam Protection), double opt-in (Double Opt-in), cookie handling (Cookie Handling), and list logic run either way — it just gets there faster. If you ever suspect the fast path is behaving differently from the normal one, disable it with the flag above and compare; they should be identical.
Why it matters
A form that feels instant converts better than one that spins for a second, and the signup form is where you win or lose subscribers. Making that one interaction as fast as possible — by refusing to boot the whole of WordPress for it — is the “Super Speedy” approach applied where it counts most.
- Creating & Configuring Signup Forms
- Spam Protection · Double Opt-in · Cookie Handling
- Architecture Overview — the technical detail of how the fast path is wired
