Calendarly

A calendar-aware group poll. The organizer describes a meeting in plain language; guests answer from a link with no account, can connect Google Calendar, or say when they're free in their own words. An AI explains the trade-offs between times ("If Leo must be there, choose option 4; otherwise option 1 works for 4 of 5"), and the organizer picks.

Code decides, the model interprets. Free time, slot candidates, the cap of 3 AI-added slots, ranking and conditional advice are plain, tested code (src/lib/engine). The model (GLM via Z.ai) does three jobs only: read the organizer's description (parsePoll), read a guest's availability (parseStatement), and write the note (explain). Every answer must pass a schema first, and every call is logged in the ai_runs table.

Run it

Requires Node 22 and the services in .env (Supabase, Z.ai, Google OAuth, Brevo).

npm install
npm run check:env     # lists which settings are present (never prints values)
npm run dev           # http://localhost:3000

Without signing in you can try the description step on a sample calendar. To sign in with Google and connect your calendar, the Google OAuth client needs these authorized redirect URIs:

• http://localhost:3000/api/calendar/callback (and the same path on the deployed domain)
• https://<your-project>.supabase.co/auth/v1/callback (Supabase sign-in)

To try everything without Google, start with E2E_TEST_MODE=1 npm run dev and use the "Test sign-in" link. It signs you in as a test organizer with a sample calendar, and guests get a "Use a sample calendar (test mode)" link so you can try calendar answers, calendar-suggested times and "meet again". Never set E2E_TEST_MODE in production.

Tests

npm test                # engine unit tests (slots, timezones, ranking, cap, advice)
npm run test:evals      # AI golden cases against recorded answers
LIVE=1 npm run test:evals   # the same cases against the real model
npm run test:e2e        # the demo path in a browser (needs Supabase settings)

The end-to-end test builds the app, runs it with the recorded model and sample calendar, creates a poll as a test organizer, answers as two guests (one in plain language), picks a time, and then deletes what it created.

The demo

npm run demo:seed                    # demo poll owned by the test organizer (view with E2E_TEST_MODE=1)
npm run demo:seed -- [email protected]   # owned by you, after you've signed in once

This seeds a six-person group project for next week in which no time suits everyone. Sam must attend. Sam, Leo, Mei and Jordan are sample guests with made-up answers, and the app labels them that way. Priya is left unanswered so she can answer live, in plain language, during the recording.

Layout

src/lib/engine     slots, constraints, ranking, conditional advice (pure, tested)
src/lib/ai         complete(), schemas, parsePoll, parseStatement, explain, mock model
src/lib/calendar   CalendarProvider: Google, sample calendars, in-memory fake
src/lib/db         Supabase server client and queries (server only)
src/lib/email      Brevo SMTP sender and the three emails
src/app            pages: /new, /p/[token] (guest), /poll/[id] (dashboard), API routes
supabase/migrations  table definitions
devpost/           planning documents (scope, PRD, spec, build checklist)