n8n is a free Node-based source-available Workflow Automation Tool. It can be self-hosted, easily extended, and so also used with internal tools.
n8n.io vs Zapier opinions
This is not Open Source: https://github.com/n8n-io/n8n/blob/master/LICENSE.md https://opensource.org/osd
n8n is a very powerful tool for automating non-trivial processes (Merge and IF nodes available). Cheaper than Zapier since you only pay per workflow execution and not per step.
Truly Open Source. Great support for many components!
Huginn is a system for building agents that perform automated tasks for you online. They can read the web, watch for events, and take actions on your behalf. Huginn's Agents create and consume events, propagating them along a directed graph.
Huginn vs Zapier opinions
It is open source and self hosted, hence YOU retain ownnership of your accounts and data flows.
With over 20 million downloads, Directus is the world's first Open Data Platform for instantly turning any SQL database into an API and beautiful no-code app.
Beehive is an event and agent system, which allows you to create your own agents that perform automated tasks triggered by events and filters. It is modular, flexible and really easy to extend for anyone.
Automatisch is a business automation tool that lets you connect different services like Twitter, Slack, and more to automate your business processes. It is a software designed to help streamline your workflows by integrating the different services.
ChainJet is a decentralized platform for building on-chain or off-chain task automations without having to code custom solutions. With ChainJet, users can integrate multiple services to automate all kinds of tasks.
Bridges between a growing number of protocols: mattermost, IRC, gitter, xmpp, slack, discord, telegram, rocketchat, steam, twitch, ssh-chat, zulip, whatsapp, keybase, matrix, microsoft teams, and more with REST API (mattermost not required!).
A flexible, customizable, open source platform that provides core integration capabilities as a service.
MESG is a flexible, decentralized development framework that allows the easy reuse of application components, while providing monetization avenues so open-source developers can get rewarded for their work.