Dev tools · alternatives · 2026
24 alternatives to Mattermost 1.0
Open source Slack alternative
Below are 24 products that do a similar job, ranked by how close each is in meaning and then by launch-day votes. Mattermost 1.0 launched in 2015; newer entries below may have overtaken it.
- 1
- 2
- 3
Slack▲2,714Be less busy. Real-time messaging, archiving & search.
2013 · slack.com · its alternatives →
- 4
Hello HN, I am building Docmost, an open-source collaborative wiki and documentation software. It is an open-source alternative to Confluence and Notion. I have been working on it for the past 12 months. This is the first public release (beta). The rich-text editor has support for real-time collaboration, LaTex, inline comments, tables, and callouts to name a few. Features - Collaborative real-time editor - Spaces (Teamspace) - User permissions - Groups - Comments - Page history - Nested pages - Search - File attachments You can find screenshots of the product on the website. Website:…
2024 · github.com · its alternatives →
- 5
A couple of years ago, I had an interesting idea. What if there was a marketplace where all the underlying tech was open-source? The order management system, the storefront, customer support, etc. The marketplace would simply connect to the seller’s infra instead of locking them in. If, for some reason, the seller is removed from the marketplace, their software stays with them and they can continue accepting orders directly. This model can be used to disrupt any marketplace from AirBNB to UberEats: building tech for home renters and restaurants and later, leveraging that to build a competing…
2022 · openship.org · its alternatives →
- 6
- 7
Matterhorn▲163Simple and light-weight project management tool
2015 · matterhorn.io · its alternatives →
- 8
Client library for Minimal Chat. Contribute to minimalchat/client development by creating an account on GitHub.
2017 · github.com · its alternatives →
- 9
Matterwiki▲227A simple, beautiful, and open source wiki for teams
2017 · nishantarora.org · its alternatives →
- 10MY
2015 · matterhorn.io · its alternatives →
- 11
Compass▲295Ask Slack about your data and get answers instantly in chat
Dec 2025 · compass.dagster.io · its alternatives →
- 12
Discover open source alternatives to your proprietary SaaS
2022 · opensourcealternative.to · its alternatives →
- 13
- 14
Open SaaS▲505Open-source & 100% free React & Node.js SaaS starter
2024 · github.com · its alternatives →
- 15
Recognize teammates with Kudos, feedback, & rewards in Slack
2021 · matterapp.com · its alternatives →
- 16
A small, open-source alternative to Slack
2017 · totaljs.com · its alternatives →
- 17
- 18
Open-source live-chat, email support, omni-channel desk. An alternative to Intercom, Zendesk, Salesforce Service Cloud etc. 🔥💬 - chatwoot/chatwoot
2019 · github.com · its alternatives →
- 19
- 20
Use sparingly, or forever lose your friends.
2018 · chromewebstore.google.com · its alternatives →
- 21
- 22
Buzz▲161Your people, your agents, your project — all in one place
Jul 2026 · buzz.xyz · its alternatives →
- 23
Real-time task management meets real-time communication
2015 · blog.hiveflux.com · its alternatives →
- 24
SSOReady▲144Open source developer tools for enterprise single sign-on
2024 · github.com · its alternatives →
Also compare
Ranked by how close each launch is in meaning, then by votes. Prices were read from each product’s own site when checked and can change. Refine with your own description →