An open-source & self-hostable AWS SES / SendGrid / Mailchimp / Resend / Loops alternative.

An open source collection of animated, interactive & fully customizable React components for building memorable websites.

Send usage data from your web app or site to PostHog, with autocapture.

PostHog FOSS is a read-only mirror of PostHog, with all proprietary code removed. NOTE: This repo is synced automatically from the main PostHog repo. Please raise any issues and PRs there.

🦔 PostHog provides open-source web & product analytics, session recording, feature flagging and A/B testing that you can self-host. Get started - free.

The Open-Source Email Platform

Queueing jobs in Postgres from Node.js like a boss

🏓 The open-source synthetic monitoring platform 🏓

The open source coding agent.

Odoo. Open Source Apps To Grow Your Business.

a fast, modern browser for the npm registry

The open-source notification Inbox infrastructure. E-mail, SMS, Push and Slack Integrations.

Fair-code workflow automation platform with native AI capabilities. Combine visual building with custom code, self-host or cloud, 400+ integrations.

The TypeScript AI agent framework. ⚡ Assistants, RAG, observability. Supports any LLM: GPT-4, Claude, Gemini, Llama.

Massimo is an API SDK client and CLI tool for creating clients for remote OpenAPI or GraphQL APIs

OpenTelemetry observability platform

Open Source HR and Payroll Software

Web framework built on Web Standards

Platform to create, curate and host MCP servers ⚒️

Free, open source crypto trading bot

The Web Data API for AI - Turn entire websites into LLM-ready markdown or structured data 🔥

Logging that makes sense. Wide events, structured errors, zero chaos.

The modern link attribution platform. Loved by world-class marketing teams like Twilio, Buffer, Framer, Perplexity, Vercel, and more.

A collaborative list of resources for developers

coss.com is the new holding company of cal.com, the pioneers of open source scheduling infrastructure and cal.com continues to be the 'google search' of our alphabet.