10 Best Open Source Projects using Cal.com in 2026

Novu

The open source Inbox component and notification platform

Stars
38,936
Forks
4,276
Last commit
8 hours ago

A powerful, open-source notification infrastructure for developers to manage and send multi-channel notifications with ease.

Open Source Alternative to:

Customer.io

Comp AI

Automate SOC 2, HIPAA, GDPR & ISO 27001 and beyond

Stars
1,540
Forks
298
Last commit
9 hours ago

Automate compliance with AI agents and 500+ integrations. Get audit-ready in days with continuous evidence collection, policy generation, and real-time monitoring.

Open Source Alternative to:

Vanta

Twenty

Streamline customer relationships with modern CRM

Stars
45,508
Forks
6,318
Last commit
8 hours ago

Open-source CRM platform for efficient customer data management, collaboration, and relationship nurturing

Open Source Alternative to:

HubSpot

Cal.com

Streamline scheduling, boost productivity, simplify life

Stars
42,351
Forks
13,131
Last commit
16 hours ago

An open-source scheduling platform that simplifies appointment booking, integrates seamlessly, and enhances team collaboration.

Open Source Alternative to:

Calendly

Suna

AI agent that autonomously handles real-world tasks

Stars
19,705
Forks
3,405
Last commit
8 hours ago

Open source AI assistant that executes complex tasks from market research to travel planning through natural conversation, with full transparency and community-driven development.

Open Source Alternative to:

Manus

Formbricks

Privacy-first surveys that respect your data ownership

Stars
12,172
Forks
2,227
Last commit
9 hours ago

Open source experience management platform for gathering user feedback on websites and apps. GDPR-compliant with self-hosting options and seamless integrations.

Open Source Alternative to:

Google Forms

Helicone

Build reliable AI apps with comprehensive observability

Stars
5,609
Forks
561
Last commit
4 days ago

Open-source platform for logging, monitoring, and debugging LLM applications. Route, debug, and analyze AI apps with comprehensive observability tools.

Open Source Alternative to:

DataDog

UnInbox

Transform team email into efficient collaborative workflows

Stars
1,725
Forks
126
Last commit
3 months ago

Streamline team communication with shared inboxes, unlimited email addresses, and customizable workflows. Perfect for modern businesses seeking organized email management.

Open Source Alternative to:

Microsoft Teams

Wraps

Code-first email platform that deploys to your AWS

Stars
44
Forks
6
Last commit
10 hours ago

Build email templates as React components and automations in TypeScript. Deploy to your AWS account with SES integration. Marketing teams edit content without code.

Open Source Alternative to:

Resend

Abby

Type-safe feature flags and remote config for developers

Stars
166
Forks
23
Last commit
10 months ago

Abby offers open-source, fully typed feature flagging and remote configuration for React and Next.js, with multi-environment testing and debugging tools.

Open Source Alternative to:

LaunchDarkly

Stars
Forks
Last commit

Stars
Forks
Last commit

Stars
Forks
Last commit

Stars
Forks
Last commit

Stars
Forks
Last commit

Stars
Forks
Last commit

Novu

The open source Inbox component and notification platform

Stars
38,936
Forks
4,276
Last commit
8 hours ago

A powerful, open-source notification infrastructure for developers to manage and send multi-channel notifications with ease.

Open Source Alternative to:

Customer.io

Comp AI

Automate SOC 2, HIPAA, GDPR & ISO 27001 and beyond

Stars
1,540
Forks
298
Last commit
9 hours ago

Automate compliance with AI agents and 500+ integrations. Get audit-ready in days with continuous evidence collection, policy generation, and real-time monitoring.

Open Source Alternative to:

Vanta

Twenty

Streamline customer relationships with modern CRM

Stars
45,508
Forks
6,318
Last commit
8 hours ago

Open-source CRM platform for efficient customer data management, collaboration, and relationship nurturing

Open Source Alternative to:

HubSpot

Cal.com

Streamline scheduling, boost productivity, simplify life

Stars
42,351
Forks
13,131
Last commit
16 hours ago

An open-source scheduling platform that simplifies appointment booking, integrates seamlessly, and enhances team collaboration.

Open Source Alternative to:

Calendly

Suna

AI agent that autonomously handles real-world tasks

Stars
19,705
Forks
3,405
Last commit
8 hours ago

Open source AI assistant that executes complex tasks from market research to travel planning through natural conversation, with full transparency and community-driven development.

Open Source Alternative to:

Manus

Formbricks

Privacy-first surveys that respect your data ownership

Stars
12,172
Forks
2,227
Last commit
9 hours ago

Open source experience management platform for gathering user feedback on websites and apps. GDPR-compliant with self-hosting options and seamless integrations.

Open Source Alternative to:

Google Forms

Helicone

Build reliable AI apps with comprehensive observability

Stars
5,609
Forks
561
Last commit
4 days ago

Open-source platform for logging, monitoring, and debugging LLM applications. Route, debug, and analyze AI apps with comprehensive observability tools.

Open Source Alternative to:

DataDog

UnInbox

Transform team email into efficient collaborative workflows

Stars
1,725
Forks
126
Last commit
3 months ago

Streamline team communication with shared inboxes, unlimited email addresses, and customizable workflows. Perfect for modern businesses seeking organized email management.

Open Source Alternative to:

Microsoft Teams

Wraps

Code-first email platform that deploys to your AWS

Stars
44
Forks
6
Last commit
10 hours ago

Build email templates as React components and automations in TypeScript. Deploy to your AWS account with SES integration. Marketing teams edit content without code.

Open Source Alternative to:

Resend

Abby

Type-safe feature flags and remote config for developers

Stars
166
Forks
23
Last commit
10 months ago

Abby offers open-source, fully typed feature flagging and remote configuration for React and Next.js, with multi-environment testing and debugging tools.

Open Source Alternative to:

LaunchDarkly

Open Source Projects using Cal.com

A curated collection of the 10 best open source software using Cal.com. Find the most popular and trending open source projects to learn from, contribute to, or use in your own projects.

Browse tools using Cal.com by category

AI Agent Platforms using Cal.com

Appointment Scheduling Tools using Cal.com

Compliance Automation Tools using Cal.com

CRM Systems using Cal.com

Customer Communication Platforms using Cal.com

Email Clients using Cal.com

Email Marketing & Newsletter Tools using Cal.com

Feature Flag Tools using Cal.com

Feedback & Feature Request Management Tools using Cal.com

Form Builder Tools using Cal.com

Log Management Tools using Cal.com

Machine Learning Infrastructure Tools using Cal.com

Push Notification Services using Cal.com

Survey Tools using Cal.com

Team Chat & Messaging Tools using Cal.com

Browse tools using Cal.com by category

AI Agent Platforms using Cal.com

Appointment Scheduling Tools using Cal.com

Compliance Automation Tools using Cal.com

CRM Systems using Cal.com

Customer Communication Platforms using Cal.com

Email Clients using Cal.com

Email Marketing & Newsletter Tools using Cal.com

Feature Flag Tools using Cal.com

Feedback & Feature Request Management Tools using Cal.com

Form Builder Tools using Cal.com

Log Management Tools using Cal.com

Machine Learning Infrastructure Tools using Cal.com

Push Notification Services using Cal.com

Survey Tools using Cal.com

Team Chat & Messaging Tools using Cal.com