ShowPony : a guest list you can build in an afternoon

Mira runs rooftop events for a small studio. She needs one link to share, a guest list that fills itself, and a dashboard she never has to redesign. ShowPony is that app built on Kumiko from end to end, with real screenshots from a Playwright runner (bun run screenshots in the show-pony repo).

This tutorial is the whole build: install, routing, data model, anonymous RSVP, mail, deploy. Every chapter ends with the complete file it produced.

What you’re building

Two surfaces, one codebase:

Who	URL	What they see
Host (logged in)	`show-pony.localhost:4180`	Events, guest list, team admin
Platform operator (sysadmin)	same apex	Platform workspace only: tenants, users, audit (not Mira’s Events)
Guest (anonymous)	`demo.show-pony.localhost:4180/e/<slug>`	Invite page + RSVP form

Surface	Local	Cloud
Host login (apex)	`http://show-pony.localhost:4180/login`	`https://show-pony.kumiko.rocks/login`
Demo invite (rooftop)	`http://demo.show-pony.localhost:4180/e/rooftop-launch`	`https://demo.show-pony.kumiko.rocks/e/rooftop-launch`
Acme invite (offsite)	`http://acme.show-pony.localhost:4180/e/acme-offsite`	`https://acme.show-pony.kumiko.rocks/e/acme-offsite`

Demo accounts. Local dev uses the values below; production uses Pulumi-injected credentials:

Role	Email	Password
Tenant admin (host)	`[email protected]`	`changeme`
System admin	`[email protected]`	`changeme`

The host is decided by the subdomain in the request, never by anything the guest sends. That’s chapters 4 and 7.

The product tour

Host dashboard

Events, forms, and guest lists are schema-driven. CRUD needs no custom React.

Edit event form filled with Rooftop Launch Party

Invite branding (host)

Per-tenant hero image, accent colour, and layout control what guests see on /e/<slug>.

Invite branding settings for the demo tenant

Guest invite page

Custom React powers the public surface: hero, copy, calendar link, and RSVP card.

Public invite page with hero and RSVP form

Acme Offsite RSVP, invite on the acme subdomain (separate tenant)

Run it locally

Bun + Docker:

git clone https://github.com/CosmicDriftGameStudio/show-pony
cd show-pony
cp .env.example .env
docker compose up -d
bun install
bun dev

Open http://show-pony.localhost:4180 and log in as [email protected] / changeme.
Create an event with slug rooftop-launch, or jump to the live demo for pre-seeded Rooftop Launch Party on demo and Acme Offsite RSVP on acme (chapter 11).
Share http://demo.show-pony.localhost:4180/e/rooftop-launch with a guest.
Watch the guest list fill up after an RSVP.

Live: show-pony.kumiko.rocks · demo event (read-only; RSVP locally)

How it fits together

Host (logged in)                          Guest (anonymous)
  apex.show-pony.…    ── creates ──▶ event
                                     │
                          shares the link
                                     │
                                     ▼
                          demo.show-pony.…/e/slug
                                     │
                                RSVP form ── submits ──▶ rsvp
                                     │
  apex.show-pony.…    ◀── guest list ──┘

The chapters

Install: clone, Docker, bun dev.
Look and feel: lavender brand + i18n.
Mount the foundation: auth, tenant, shell.
Apex and subdomains: hostname → tenant.
The data model: event and rsvp.
Wire the business logic: handlers, screens, nav.
Anonymous RSVP: guest write without login.
Dashboard from schema: what the host sees.
The public surface: invite page + RSVP UX.
Mail and calendar: confirmation + .ics.
Seed and ship: demo content + production image.
Marketing apex: public landing on /.
Legal pages: Impressum / privacy in marketing chrome.
PII and compliance: guest data, legal text vs GDPR runtime.
Plans & Stripe checkout: tiers, caps, host billing screen.

Read in order, or jump to the chapter that matches what you’re stuck on.