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The AI stack

The whole five-layer mapL3InfrastructureL4Models & toolingL5Applications

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About

How we rank & score
Best of · 4 tools ranked

The best Scheduling & Booking

Every option ranked — open-source, self-hostable, and commercial — by our transparent Sovereignty Score, with honest trade-offs so you choose what fits you, not us.

Tools for sharing availability and letting others book meetings or appointments without email back-and-forth — booking-link platforms, group meeting-time polls, and appointment systems for service businesses.

L5Applications — layer 5 of the AI stack
  1. 1

    Easy!Appointments

    Top pickOpen source

    Mature, self-hosted appointment booking with Google Calendar sync.

    Free, self-hosted (own server/hosting cost only). Optional paid add-ons: SMS reminders, payment processing, custom development, and managed hosting from the maintainer. · in our Calendly comparison →

    91
    sovereignty
    What is Easy!Appointments? →
  2. 2

    Appointments for Nextcloud

    Open source

    Calendly-style booking pages built into your existing Nextcloud.

    Free; installed from the Nextcloud App Store into an existing Nextcloud instance. Optional donations support the solo maintainer. · in our Calendly comparison →

    88
    sovereignty
    What is Appointments for Nextcloud? →
  3. 3

    Cal.diy

    Open source

    MIT-licensed community edition of the Cal.com scheduling codebase.

    Free, self-hosted. No official managed hosting or support channel; Cal.com's paid hosted product is a separate, now closed-source, offering. · in our Calendly comparison →

    85
    sovereignty
    What is Cal.diy? →
  4. 4

    Rallly

    Open source

    Open-source group scheduling and meeting-time polling.

    Free, self-hosted via Docker. A hosted version exists at rallly.co with an optional paid Pro tier for extra features. · in our Calendly comparison →

    84
    sovereignty
    What is Rallly? →

Replacing a specific tool?

Head-to-head comparisons for each popular scheduling & booking product.

Alternatives to Calendly

4 vetted options · top pick Easy!Appointments

Straight head-to-heads

Two scheduling & booking tools, side by side — verified facts and a plain verdict.

Easy!Appointments vs Appointments for Nextcloud→Easy!Appointments vs Cal.diy→Easy!Appointments vs Rallly→Appointments for Nextcloud vs Cal.diy→Appointments for Nextcloud vs Rallly→Cal.diy vs Rallly→
The Macrostack brief

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