11 Best Open Source Pumble Alternatives
A curated collection of the 11 best open source and self-hosted alternatives to Pumble in 2026.
Looking for a free, privacy-friendly, or self-hosted replacement for Pumble in 2026? The top open-source alternative is Macro Chat — Team chat with AI agents and unified workspace.
Other highly rated open-source Pumble alternatives include Rocket.Chat, Buzz and Mattermost.
Team chat with AI agents and unified workspace
Macro is a modern team collaboration platform that unifies chat, email, tasks, and AI agents into a single workspace. Designed for teams that want to reduce context switching, Macro offers inline threads, instant @mention sharing, and AI-powered assistance with full workspace context. - Inline threads & forum discussions: Keep conversations organized with threaded replies directly below messages. - @mention sharing: Instantly share docs, tasks, or email threads with channel members without permission dialogs. - Unified inbox: Combine email, chat, and tasks in one place for streamlined workflows. - AI agents with context: Type @Macro to summon an agent that summarizes missed conversations, drafts replies, or answers questions using your workspace data. - Built-in tasks & docs: Create and manage tasks and documents natively within the chat interface. - Unified search: Search across channels, email, docs, and tasks with a single query. - Open source (AGPLv3): Self-hostable and auditable, ensuring full control over your data. - Enterprise-ready: Includes CRM, calls, and advanced collaboration tools in a single seat. Macro is open source under the AGPLv3 license and can be self-hosted for complete data control. The platform prioritizes security with private, encrypted workspace data and offers flexible deployment options. For teams preferring a managed solution, Macro provides a hosted version with all features included.
Secure team chat with voice, video & AI
Rocket.Chat is a secure, open-source communication platform that centralizes real-time messaging, voice, video, and AI capabilities for teams and organizations. Designed for mission-critical operations, it offers robust data privacy, sovereignty, and compliance features. - Unified Communication: Real-time messaging, voice and video calls in a single platform - Multi-Environment Deployment: Cloud, on-premises, or air-gapped environments - Data Privacy & Sovereignty: End-to-end encryption, access controls, and compliance features - AI Integration: Privacy-first AI capabilities for workflow optimization - Cross-Organization Collaboration: Secure communication across teams and external stakeholders - Governance & Monitoring: Complete messaging governance and audit trails - Integration Hub: Connect tools, custom apps, and processes into one platform - Accessibility Compliance: WCAG 2.1 Level AA conformance for regulated procurement Rocket.Chat is fully open-source (MIT license) and can be self-hosted on any infrastructure. The platform supports Docker, Kubernetes, and traditional server setups. Enterprise-grade security features include SSO, 2FA, and granular permission controls. Documentation and developer guides are available for custom deployments and integrations.
Collaborative workspace for human and AI agent teams
Buzz is a collaborative workspace designed for human and AI agent teams to work together seamlessly. It consolidates communication, project management, and development tools into a single shared space. - Unified Collaboration: Chat with teammates and specialized agents in shared rooms, keeping context, decisions, and next steps in one place. - Agent Integration: Invite and manage AI agents tailored to your workflows, enabling them to collaborate with your team’s agents. - Project Management: Turn discussions into plans, code, reviews, and PRs without switching between tools. - Open Source: Fully open source project with community-driven development. - Enterprise Ready: Waitlist available for an enterprise version with company-wide access and advanced agent management. Buzz is an open source project available on GitHub. It can be self-hosted for full control over data and infrastructure. The project is built by Block and supports GDPR compliance.
Secure collaboration platform for mission-critical teams
Mattermost is an open-source collaboration platform designed for mission-critical work environments where security, compliance, and operational sovereignty are paramount. - Secure Collaboration: End-to-end encrypted messaging with granular access controls and audit logging - Mission-Critical Workflows: Built-in Playbooks for repeatable processes and incident response - AI Integration: Enterprise-grade AI capabilities with agentic workflows and MCP support - Multi-Domain Security: Air-gapped, on-prem, and private cloud deployment options - Interoperability: Native integrations with Microsoft Teams, Atlassian, GitLab, and 1,000+ other tools - Compliance Ready: SOC 2, HIPAA, FedRAMP, and ITAR compliant deployments - Developer Tools: Built-in code review, CI/CD pipelines, and API-first architecture - Global Trust: Deployed by governments, militaries, and Fortune 500 enterprises Mattermost is available as both a cloud-hosted solution and self-hosted open-source software. The self-hosted version can be deployed on any infrastructure with Docker, Kubernetes, or bare metal installations. Supports PostgreSQL, MySQL, and enterprise-grade security configurations. Full documentation available at docs.mattermost.com.
Organized team chat for distributed teams
Zulip is a powerful team chat application that organizes conversations into streams and topics, making it easier to follow discussions and reduce noise. Designed for distributed teams, it combines the flexibility of chat with the organization of email threads. - Stream-based organization: Conversations are structured into streams and topics for better clarity - Cross-platform support: Available as desktop, mobile, and web applications - Powerful search: Advanced search capabilities to find any conversation or file - Integrations: Extensive API and integration support for popular tools - Privacy controls: Strong privacy features including end-to-end encryption options - Self-hosting: Full control over your data with self-hosted deployment - Scalability: Suitable for teams of all sizes from small groups to large organizations - Open source: Community-driven development with transparent codebase Zulip is open source and can be self-hosted on your own infrastructure. The project provides comprehensive documentation for installation and maintenance. Cloud hosting is also available through Zulip Cloud for teams that prefer a managed solution. The software is built with Python, Django, and PostgreSQL, making it suitable for most server environments.
Privacy-first open source chat app with voice & video
Fluxer is a privacy-first, open source chat application designed for friends, groups, and communities. It offers a comprehensive suite of communication features including text messaging, voice and video calls, screen sharing, and organized community channels—all while prioritizing user privacy and control. - Messaging: Full Markdown support, private DMs, group chats, and organized community channels with file sharing and link previews. - Voice & Video: Multi-device calls, built-in screen sharing, noise suppression, echo cancellation, and camera control. - Moderation Tools: Granular roles and permissions, audit logs, webhooks, and bot support for transparent community management. - Search & Navigation: Quick search through message history, filter by author or date, and a quick switcher with keyboard shortcuts. - Customization: Upload custom emojis and stickers, save media, apply custom CSS themes, and toggle compact mode. - Self-Hosting: Fully open source (AGPLv3) with no licensing fees. Host your own instance and switch between multiple servers. - Global Voice Regions: Sixteen voice regions across six continents for optimized call quality. - Multilingual Support: Available in over thirty languages with community-driven translations. Fluxer is fully open source under the AGPLv3 license. The backend can be self-hosted on your own hardware, and the same apps are used for both official and self-hosted instances. No license keys or cut-down community editions are required. For setup instructions, refer to the self-hosting guide.
Secure decentralized team messaging & collaboration
Element is a Matrix-based end-to-end encrypted messenger and secure collaboration app. It operates on the decentralized Matrix network, enabling interoperability and easy connections between different services. - End-to-end encryption for all communications - Decentralized architecture built on the open Matrix protocol - Self-hosting capability for digital sovereignty - Interoperability with other Matrix-compatible services - Cross-platform support (web, desktop, mobile) - Group messaging & collaboration tools - File sharing & voice/video calls - Enterprise-grade security with compliance options Element is built on the Matrix open standard and can be self-hosted for complete data control. The platform supports various deployment options including Docker containers and Kubernetes. For organizations requiring managed services, Element Matrix Services provides hosted solutions with enterprise support. Matrix protocol ensures data portability and interoperability across different Matrix clients and servers.
Self-hosted Slack alternative with code access
Campfire is a self-hosted group chat system designed for teams who want to avoid recurring subscription fees. Built by Basecamp, it offers a familiar Slack-like interface with essential features like direct messages, @mentions, and mobile support. - Self-hosted: Install on your own server or cloud provider (AWS, DigitalOcean, Hetzner, etc.) - No subscriptions: One-time setup with no ongoing fees - Essential chat features: Rooms, DMs, @mentions, dark mode, and mobile PWA support - Customizable: Full access to source code under MIT License for modifications - Private rooms: Create private or public rooms for different teams or projects - Air-gapped support: Works offline or on isolated networks - Automatic updates: Optional daily update checks with manual override - Chatbots: Simple HTTP API for integrating custom chatbots - Installation: Single command via ONCE CLI (curl https://get.once.com/campfire | sh) - System requirements: Scales from 250 users (2GB RAM, 1CPU) to 10,000 users (64GB RAM, 32CPU) - Compatibility: Runs on laptops, local servers, or cloud infrastructure - Mobile: Progressive Web App (PWA) with push notifications and badges - License: MIT License (free and open source)
Open-source group chat for communities
Stoat is the open-source group chat app for friends and communities that works the way you always wished it would. Built in Europe under strict data protection laws, it offers servers, channels, voice chat, file sharing, and more—without ads, data mining, or shady partnerships. - Servers & Channels: Organize conversations with dedicated servers and channels. - Voice Chat: Built-in voice chat for real-time communication. - File Sharing: Share files up to 20MB with no subscription required. - Markdown Support: Write messages with rich formatting. - Role-Based Permissions: Intuitive moderation tools for community management. - Cross-Platform Sync: Syncs across Windows, macOS, Linux, Android, iOS, and web. - Custom Themes: Theming options and CSS support for personalization. - Group DMs: Supports up to 50 members in group DMs. - Public API: Developers can build custom clients or bots using the powerful API. - Open Issue Tracker: Community-driven development with an open issue tracker. Stoat is open-source and can be self-hosted for full control over your data. The software is built with privacy in mind, ensuring no ads, data mining, or shady partnerships. Hosting is free and open, allowing you to manage your community without external dependencies. Download | Open Web App | GitHub Repository
Peer-to-peer encrypted messaging without servers
Whether it's for an organization, a community, or a group chat with friends, Quiet lets you control all your data without running your own servers. !Mockup of Quiet app on desktop and mobile - Peer-to-peer messaging: Syncs directly between devices over Tor, eliminating the need for central servers - End-to-end encryption: All data encrypted between member devices - Slack-like interface: Organize chats in channels for structured conversations - No email or phone required: Create or join communities without sharing personal contact details - File sharing: Send and receive files of unlimited size - Tor integration: Built-in Tor network for enhanced privacy and anonymity - Cross-platform support: Available for macOS, Windows, Linux, Android, and iOS - Community control: Data remains solely on users' devices, ensuring full ownership Quiet operates as a fully peer-to-peer network, meaning no servers are required to run the service. Users can install the app on their devices and create communities directly. The project is open-source and available on GitHub.
Secure open-source messenger for professionals
Twake Chat is a secure and private-by-default messenger designed for professional communication. Built on the decentralized Matrix protocol, it ensures high levels of security and privacy while offering features like end-to-end encryption, multi-account support, and cross-device synchronization. - End-to-End Encryption (E2EE): Secure conversations with customizable security levels. - Multi-Account Support: Switch between personal and work accounts seamlessly. - Cross-Platform Sync: Synchronize messages and data across all devices (mobile, tablet, laptop). - Matrix Protocol Integration: Communicate across platforms like Telegram, Discord, and Signal via bridges. - Jitsi Integration: Built-in videoconferencing for improved collaboration. - Corporate Directory (SSO): Facilitate communication with contacts from phone books and corporate directories. - On-Premises Deployment: Host Twake Chat on your own infrastructure for enhanced security and performance. - User-Friendly Interface: Simple registration, usage, and maintenance with strong community support. Twake Chat is powered by the Matrix protocol and can be deployed on-premises or in the cloud. The open-source server (ToM-server) is available on GitHub, and the project offers technical documentation for self-hosting. Mobile apps are available for both Android and iOS.
About Pumble
Business communication and team messaging software. Unlimited users, direct and group messages, and unlimited message history.