Kong Reviews
Kong Reviews

Cal.com tech stack

Cal.com is open-source scheduling for people and teams. It runs on Next.js, Prisma, PostgreSQL, Upstash and 8 more, read from its public repo calcom/cal.diy.

Booking pages, round-robin and collective scheduling, routing forms and embeds, with calendar sync for Google, Outlook and Apple. Free for individuals; teams and organisations pay per seat.

Productivity · web, ios · https://cal.com · 49,459 GitHub stars, MIT (2026-10-28) · App Store 4.9 from 216 ratings (2026-10-28)

Built with

Frontend

  • Next.js (apps/web/package.json: next)

Backend

  • Prisma (packages/prisma/package.json: prisma)

Database

  • PostgreSQL (docker-compose.yml: postgres)
  • Upstash (package.json: @upstash/redis)

Sign-in

  • Auth.js (NextAuth) (package.json: next-auth)

Hosting

  • Vercel (package.json: @vercel/edge-config, @vercel/og)

Payments

  • Stripe (package.json: @stripe/stripe-js)

Email

  • SendGrid (.env.example: SENDGRID_API_KEY)

Other

  • Twilio (.env.example: TWILIO_VERIFY_SID)
  • Intercom (.env.example: NEXT_PUBLIC_INTERCOM_APP_ID)

Analytics

Monitoring

  • Sentry (package.json: @sentry/nextjs)

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