Since 2016
Nine years of online session booking, without interruption
A centre opens its slots, clients book, pay and get their invoice. The service has been running since 2016 and has followed every version of our stack.

slots opened for booking since 2016
payments taken online since 2016
client accounts created since 2016
The context
Booking a slot is simple as long as one person comes at a time. Add prepaid session packs, sessions for two or three, company accounts paying for their staff, cancellations and slots closed the day before, and a spreadsheet no longer holds — the phone becomes the centre's real cost.
The workflow, in motion
One open slot, two counters moving
The centre publishes its availability. On booking, the seat in the slot and the session in the prepaid pack are both counted down in one gesture — which a paper sheet cannot hold.
Mon
4
Tue
—
Wed
6
Thu
3
Fri
2
Sat
5
Sun
—
Seats left on each day open for booking.
2 pm slot
3 / 6 — seats taken, alone, in pairs or in threes
Prepaid pack
9
sessions left, counted down at booking rather than on arrival.
A reminder goes out before the session; cancelling stays possible on both sides.
The invoice is issued with no manual step, including when a company pays for its staff.
The centre opens and closes its own slots: a schedule change goes through nobody.
What we did
- The public calendar: open, full or closed slots, booking alone, in pairs or in threes.
- Prepaid session packs, counted down at each booking, with their expiry date.
- Online payment and the invoice issued straight away, including when a company pays for its staff.
- Email and SMS reminders, and cancellation from both sides — client and centre.
- The calendar embedded in the centre's own site, rather than one more site to promote.
- Porting the application to the current stack, with no downtime and no loss of history.
What changed
- The centre opens and closes its own slots: a schedule change never goes through us.
- Payment comes before the session, so prepaid packs stay correct with no admin work.
- Booking lives inside the centre's own site, where clients already arrive.
- Nine years of continuous service, version changes included.
The services involved
This engagement drew on the following expertise. Each has its own page, with its method and its deliverables.
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