Open alternatives4
Open-source apps that replace Zendesk and Intercom

Chatwoot is a customer support platform that puts chats, email and social messages from customers into one shared inbox. It is for businesses that want to run their own support software and keep control of their customer data.

Papercups is a customer support tool that lets a business chat with website visitors and answer support emails and texts in one place. It is meant for companies that want to host their own customer data instead of using a third-party service.
Zammad is a web-based helpdesk where support teams handle customer messages from email, chat, phone and social media in one place. It is for companies and support staff who answer customer questions.
UVdesk is a web-based helpdesk system that lets a support team manage customer requests as tickets from email and a support portal. It is aimed at businesses that want to run their own customer support desk.
What's missing
What people still miss here, and wish existed. Upvote what matters to you.
Before you build
Planning something for customer support? See what exists first, so you can reuse parts or explain what's different. Paste this into any AI assistant:
Fix the list itself
A project or closed app missing from this list, or a mistake on it? These open a short form on GitHub, and a mod reviews it. To say what a project can't do, use What's missing.
About this page
Replaces fully means it does the main job of these apps; Replaces partly means it covers some of it.
Licenses: every project here uses an open-source license (what each one means). Open core means some parts are paid or under another license.
GitHub stars are shown for reference. They measure popularity, not whether it replaces anything.
Verified means r/TrueOpenSource mods checked it: open-source license, maintained, and it really does the job.
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