Slotly.software · Book a slot, plainly · 2026

A slot. Booked. No ceremony.

Most booking tools want to be a platform before you have even shared your first link — event-type builders, branding wizards, tiers that quietly cap the free plan or ration white-label until you talk to sales. Slotly.software is built to skip all of that. You set your hours, you share one link, someone books a slot that is actually free.

That is the whole product. No booking cap on the free plan, no per-seat pricing until you actually add seats at Team, and white-label — your own name on the page instead of ours — priced at Team rather than held behind an Enterprise call. It runs on the same shared fixed-slot booking engine the schedule.software family is built on, brought here to the practitioner who wants the fewest possible words between sharing a link and it being booked.

Reserve early access See the plain version

1link to share, and nothing to configure before you share it — no event-type builder, no branding step

0monthly booking cap on the free plan — the pricing commitment this brand is being built around, not a live signup today

3correctness invariants already built and unit-tested in the shared engine underneath — no double-book, per-slot capacity, overlap rejection

0commission taken out of a booking at any planned tier — a pricing commitment, not a live guarantee, because there is nothing to take a commission from yet

Why slotly.software exists — the gap between a personal link and a suite

The two ways a booking tool stops being simple: a ceiling you hit later, or a setup you face first.

A lot of single-link scheduling tools are genuinely fine right up until the free plan hits a monthly booking ceiling, or until removing their branding turns out to require an Enterprise conversation. On the other side of the market, full booking suites solve the ceiling problem but ask you to configure a platform — event types, branding themes, staff roles — before you can share a single link.

Slotly.software is built to be neither. The plan is a real free tier with no booking cap, and white-label at the Team tier instead of an Enterprise-only unlock. It is not trying to be the most feature-dense product in the category; it is trying to be the plainest — one link, one page, a slot that is actually free when it says it is.

Product type	Free tier booking cap	Per-seat pricing below Team	White-label below Enterprise	Ads on the poll/booking surface
Personal-link scheduling tools	Often, on the free plan	Often, per account holder	No — Enterprise only	None
Legacy booking suites	Sometimes, on lower tiers	Often, per staff/location	No — Enterprise only	None
Free poll-only tools	No cap, but poll-only — no real booking	N/A	N/A	Often, ad-supported
Slotly.software (planned)	Planned — no cap on Free	Planned — per-account, not per-seat, below Team	Planned — at Team, not Enterprise	None, at any tier

The bottom row is us, and it says “planned” in every cell for a reason: it describes a product being built, not one you can compare against the others by signing up for it this week. The engine beneath it is real; the tiers are display-only figures.

The rows above describe shapes of product, not particular vendors, because any given vendor's tiers change faster than a page like this does. Calendly, Acuity, TimeTap, Setmore, Doodle, and SimplyBook.me are listed as a plain statement of which market this competes in, we make no claim about what any of them charges today, and none of their code or copy is used anywhere in this product.

What’s built — what runs today, what is in development, labelled honestly

Six things, three honest labels, and no blurring between them.

One label per item, and the labels mean narrow things. Built is the strongest thing we will say, and it still only means the mechanism exists in the shared engine — never that a client has booked a slot through slotly.software, because none has. Partial means the engine half exists and the half with our name on it does not. Planned means it is designed and nothing is built. Exactly one item below is Built.

One link, real open slots

Share one link. What a client sees is what is actually free — nothing else.

A slotly.software link shows exactly the slots that are actually free, nothing padded and nothing stale. The same shared fixed-slot engine the schedule.software family is built on backs it: the database refuses a second live booking on a window it has already given away, and where a slot holds more than one person, the remaining room is locked while it is being spent rather than merely checked beforehand. Two people reaching for the last opening both get a clean conflict they can retry — never a silent double-book. The engine is built; the public booking page/embed for this brand is in development.

Engine built · public booking page/embed in development

Free, with no booking cap

The free tier is not a trial with a ceiling — it is the plan, permanently

No monthly booking limit gates the free tier. A single practitioner who books thirty clients a month and one who books three hundred use the identical free plan, capped nowhere. This is a pricing commitment, not a live feature today: the free tier is planned as designed above, not yet shipped as a self-serve signup on this brand.

Planned · not yet built

White-label at Team, not Enterprise

Your name on the page at the Team price, not behind an Enterprise sales call

Removing the slotly.software mark from a booking page and putting an operator's own name and colors on it ships at the Team tier, priced per-seat, not held back for a custom Enterprise contract the way several incumbents in this category gate white-label. This is a packaging decision, and it is not live today -- the overlay is designed, not yet built.

Planned · overlay design complete, not yet built

A native group poll before the slot is claimed

“Which of these times works?” built into the same product, not a separate tool

Before a slot is claimed outright, an operator can send a small set of candidate times as a native, ad-free poll and let a client (or a few clients) pick the one that works, then convert the winner straight into a real booked slot on the same engine -- no separate poll tool, no ads. This is a fleet-wide build-new item shared with whenly.software's group-availability lane; it is designed, not yet built.

Planned · shared build item with whenly.software

No-double-book, at the database

A malformed overlap is rejected at the server before it can land

Two bookings whose windows intersect by even one second are rejected at the server using the canonical half-open [start, end) predicate before any write lands. This is the same overlap discipline the shared engine already carries for facility booking and conference scheduling, applied here to a single practitioner's one calendar instead of a multi-room building.

Built in the shared engine · not yet exposed on a slotly.software surface

Two-way sync & CalDAV

The part where your existing calendar stops being a separate problem — not built yet

The honest gap in a plain booking link is the calendar you already keep. Until the substrate work lands -- RFC-5545 recurrence, a CalDAV server (RFC 4791), and two-way sync with Google and Microsoft -- a slot booked here would not know about the dentist appointment already sitting in your own calendar. That work is in active development across this whole family of products and is not built; we would rather name the gap than let a feature list imply it is closed.

In active development · not yet built

How it works — the flat version

Set hours, send link, done. There is no step four.

This is the part that does not get longer as your practice gets busier: no extra configuration unlocks at volume, no wizard reappears. Steps one and two describe the surface being built; step three describes the engine underneath, which exists.

Step 1 — Publish the slots

An operator sets working hours, a slot length, and how far ahead someone can book. That is the entire setup. No event-type builder, no branding wizard to click through first.

Step 2 — Share one link

One link, one booking page, showing only the slots that are actually free right now. A client picks a time and confirms. If the operator sent a short list of candidate times instead, the client picks the one that works and that pick becomes the booked slot.

Step 3 — The database, not the booking code, decides who got it

The transaction that books a slot takes a lock on that slot’s live-booking count before it trusts the number, so the count cannot go stale between being read and being spent. Separately, a uniqueness rule on the time window lives in the database itself, so a second live booking for an already-claimed window cannot be written at all. Neither rule sits in the booking code, which is why a future code path cannot forget to apply one. Whoever loses the race gets a clean 409 they can retry — not a double-booked morning.

Pricing — three numbers, and what each one is actually for. This is not a live checkout; no card is charged.

Free is the plan, not the trial. Plus buys room. Team buys your name instead of ours.

Three tiers, because we could not honestly justify a fourth. The numbers below are the intended launch prices and nothing on this page can take money: this is not a live checkout, no card is charged, and there is no payment form here to put one into. If the shape of this pricing suits how you work, say so early — the tiers are still close enough to launch that what we hear now changes them.

Free

No booking cap · planned

One booking link, real open slots
No monthly booking limit
Same no-double-book guarantee as every tier
Slotly.software branding on the page

Plus

$8 / mo

Per account · planned

Everything in Free
Custom availability rules and buffers
Native group-poll for candidate times
Priced per account, not per seat

Team

$12 / seat / mo

White-label included · planned

Everything in Plus
White-label — your own name and colors, no slotly.software mark
Small-team shared availability
No Enterprise contract required for white-label

Reserve early access Discuss pricing for your practice

To be explicit about the money, because a pricing table implies otherwise: no money can change hands through this site. There is no payment processor connected to these tiers, no card is charged, and this is not a live checkout — the billing seam exists in the codebase and is switched off.

The boring part we did not skip

The plainest possible product still has to be right about the one thing it does.

There is an obvious temptation in a product this small: the whole thing is one link and one slot, so surely a check before the INSERT is enough. It is not. Two requests can arrive in the same millisecond, both read the slot as open, both pass the check, and both write — and the person who loses that race does not find out until they show up. Plainness is a claim about the interface, not permission to be sloppy underneath it.

So the rules are not written in the booking code at all. They are constraints the database and the server enforce, in the shared fixed-slot engine this brand sits on, which means they cannot be forgotten by a future code path that also wants to create a booking. That engine is built and unit-tested today. What is not built is the slotly.software surface in front of it — so what follows describes what the engine already refuses to do, not a booking page you can point a client at this afternoon.

Why it’s correct — what the engine underneath already refuses to do

Three invariants, already built. Plus one commitment about how they get packaged.

✓One slot cannot be sold twice

The uniqueness of a live booking is a partial-unique index, so it is the database that refuses the second one — not a check the application performs and can lose a race on. The loser of the race gets a 409 carrying the machine reason ‘already_booked’, which is a retry instruction, not an apology screen.

✓A slot that holds more than one person still cannot hold one too many

Where a slot has capacity above one, the count of live bookings is taken under SELECT … FOR UPDATE inside the transaction doing the booking, so the number cannot go stale between reading it and acting on it. Over capacity returns 409 ‘slot_full’ before anything is written.

✓A one-second overlap is still an overlap

Windows are compared with the half-open [start, end) predicate at the server, so a booking that ends at 10:00 and one that starts at 10:00 are fine, and a booking that runs one second past is refused. Because the comparison is server-side, a client that lies about its own arithmetic gets nowhere.

✓The commitment: the free plan will not get a weaker engine

The three invariants above live in the shared engine, below any notion of a plan, so there is no cheaper code path for a free account to be routed down. That is the intended design of the tiers described on this page — and the tiers themselves are planned, not running, so read this as a commitment about how we will package it rather than a report on something you can sign up for today.

What is built, what is not, and one open naming question — plainly stated

A page this plain should be plain about itself too: here is the line between what exists and what does not.

Already built in the shared fixed-slot engine: the no-double-booking partial-unique index, the per-slot transactional capacity count, and the overlap-rejection predicate. There is no slotly.software deployment serving client bookings today — the engine is built; this brand's surface on top of it is not.

In active development: the public booking page/embed for this brand, the white-label overlay, the native group-poll (shared build item with whenly.software), and two-way Google/Microsoft calendar sync plus a CalDAV server.

Payments — the seam is in place; Stripe is not enabled. There is no live checkout on this site. Slotly.software does not hold FERPA, COPPA, SOC2, or VPAT certification.

One open item that is a process step, not a build blocker: “slotly” is flagged internally as the highest name-collision-risk mark in this schedule-family wave, and a formal trademark/registry check is required before brand launch. This front door is built and this page states the pending review plainly rather than implying the name is cleared.

Reserve early access

Tell us how you actually book people, while the link is still being built.

The order of work here is deliberate: the part that is expensive to get wrong — the uniqueness constraint, the capacity count, the overlap predicate — was built first, and the part that is cheap to change — the public link, the free plan with no cap, the white-label overlay, the group poll — is being built now. That is exactly the window in which telling us what your day looks like is worth something. There is no checkout to complete and nothing is charged; a conversation, then an honest answer about when your particular use of it will be ready.

To reserve early access or book a conversation: [email protected]

FAQ

Common questions

What makes slotly.software different from dibs.software or appointments.software? Aren't they the same tool?

They run on the same shared fixed-slot booking engine, but they are three separate products built for three different buyers. Appointments.software is built for a business with more than one calendar -- multi-staff, multi-location, resource overlap. Dibs.software is a brand-forward “call dibs on a time” front door for a consumer-register solo/small-team buyer. Slotly.software is the plainest of the three: no metaphor, no platform pitch, the flattest possible description of the thing -- a slot, booked -- built for a single practitioner or a very small team who wants the fewest possible words between sharing a link and it being booked, and who eventually wants their own name on the page rather than a personality-forward brand.

Is the free tier really uncapped, or is there a booking limit hiding somewhere?

As planned, no monthly booking limit gates the free tier -- a practitioner who books thirty clients a month and one who books three hundred are on the identical free plan. This is a pricing commitment we are stating plainly here, not a live self-serve signup today: the free tier as described is planned, not yet shipped as a working signup flow.

Is white-label really available below Enterprise, or is that the usual asterisk?

As designed, white-label -- an operator's own name and colors on the booking page, the slotly.software mark removed -- ships at the Team tier, priced per seat, not gated behind a custom Enterprise contract. It is not live today: the overlay is designed, not yet built. When it ships, the price and the tier it ships at are the ones stated here.

If the product is this small, is the no-double-booking check just an if-statement?

No, and that is the one place we would rather be boring than small. It is a partial-unique index: a UNIQUE constraint on the resource and time window, restricted to bookings whose status is live, so a cancelled booking frees its window and a live one cannot be duplicated. The second concurrent write fails at the database with a unique violation, which the engine turns into a 409. The distinction matters because an if-statement can be raced and a constraint cannot — and it is the same constraint every other booking caller on this engine sits behind, so it is exercised well beyond this brand.

Is the group-poll feature the same thing as whenly.software?

No. Whenly.software is a dedicated find-a-time product -- the overlap of many participants' free windows across a real calendar substrate. Slotly's planned group-poll is a narrower, single-purpose feature inside a fixed-slot booking flow: a short list of candidate times an operator offers before a slot is claimed. The underlying poll-UI build item is shared between the two products, but the products themselves are not the same tool, and neither is a feature of the other.

Do you skim a commission on bookings, or meter by seat below Team?

No commission skim on any transaction, at any tier, as planned. Metering by seat applies only at the Team tier where white-label is priced per seat; Free and Plus are per-account, not per-seat.

Can I actually buy this right now? What happens if I click something in the pricing table?

Nothing happens, because there is nothing wired to it. The prices are the planned launch figures, this is not a live checkout, no card is charged, and there is no payment processor connected to these tiers — the only thing any button on this page does is open an email. If you want in early, that email is the mechanism, and we would talk through what your practice needs before anything is ever billed.

Is the “slotly” name final?

Not yet, and we say so here rather than pretend otherwise. Slotly carries the highest name-collision risk of any mark in this family internally, and a formal trademark/registry check is required before brand launch. That check is a pending process step, not a reason this front door isn't built today -- if the name changes before launch, the product and pricing described here do not.

What can we actually see or use right now?

Honestly: not a booking page with your name on it. What exists is the engine — availability publishing, the capacity guarantee, the uniqueness constraint, the overlap-rejection predicate — built and unit-tested in the shared core this whole family of products is assembled on, and already folded into other booking callers inside the fleet rather than written for this page. What does not exist yet is everything with the word slotly on it: the public booking link, the embed, the white-label overlay, the group poll, the calendar sync. If you want to see the difference concretely rather than take a web page's word for it, ask, and we will walk you through what is built and what is not.