No app. No account. No password.

Every project has a public enrolment page. Share the link however you already reach people — email, a WhatsApp group, a QR code on a poster, a button on your own website. There is no sign-in wall in front of it.

The page shows your organisation's logo and name, the project, and the events on offer:

• →Which days each event can run on, and the time window it sits inside.
• →How full it already is, as a fill bar — and a clear Full badge once it is.
• →Tick as many events as you want in one go.

Only a name is required. Email is optional, though someone who leaves it out will not receive their schedule or any updates. Sign-ups are rate-limited, and the capacity check is taken under a lock, so two people cannot both claim the last seat in the same instant.

Every attendee and every instructor gets their own private timetable URL, showing only the sessions they are actually in. No login, no password to forget, nothing to install.

The important part is what does not happen to that link. It is created with the person and never changes for as long as they exist. It survives every solver run, every re-run, every republish, every time you rename an event or move a session or swap a room. The link you sent in September is still the right link in April, and it now shows April's schedule.

Instructors get one too

The same kind of link, showing the sessions they are teaching along with head counts, so they walk in knowing how many people to expect. Instructors do not need accounts either.

A personal page always shows the published schedule and never your working draft. You can run the solver eleven times on a Tuesday afternoon, compare the results, and change your mind twice — nobody outside sees a thing until you publish. Nothing about the link needs to be taken down or put back up in between.

Two different things, and the difference matters.

Download to calendar

A one-time .ics file. Their calendar gets the events as they stand today, and it will not know about anything that changes later.

Subscribe to the feed

A live calendar URL they add once. It carries the weekly repeat, and it updates itself whenever you republish. Move a class on Thursday and it moves in their phone.

The feed always returns a valid calendar, even when someone currently has no sessions — so a subscription never breaks and never has to be re-added. It carries the room and location, and the instructor in the event notes.

The feed is one-way: it publishes your schedule into their calendar. It does not read their calendar back, and there is no two-way Google or Outlook sync.

Both the personal page and the full project schedule print properly and save as a PDF, with your logo, your organisation name, the project and its dates on the header. Half the world still wants a register on a clipboard and a timetable on a noticeboard.

Chasing forty people for their availability is worse than the scheduling. Turn on self-service and each attendee sets their own weekly windows from the personal link they already have — no login, no account, no extra tool.

They can also star the windows they would prefer. A plain window is a hard rule the solver will never break; a star is a preference it tries to honour but will trade away rather than leave someone unplaced. People understand the difference immediately, and you get much better data than a spreadsheet ever collects.

It is a per-project switch, off by default. Instructor availability stays admin-only on purpose.

A short list, because knowing the boundary is more useful than discovering it later. This is a scheduling tool, not a booking platform.

• →They cannot pick their own slot or swap sessions. The whole point is that the solver decides, so the result stays conflict-free.
• →They cannot cancel their own enrolment. Ask you, and you remove it.
• →They cannot pay anything. There is no attendee billing, no memberships and no packages.
• →They cannot log in. There is no attendee account, by design — the link is the identity.
• →There is no mobile app to install, and no SMS or push notifications.

When you do remove someone who had an email, they are told rather than left to wonder, and they cannot immediately re-add themselves through the public link. You can lift that block whenever you want.

A confirmation when they enrol, carrying their permanent link. Their schedule when you publish. An update when their week actually changes — and only then. Every one of those carries your logo, and every one has a working unsubscribe.

The detail is on branding and emails.