Think of it as a team messaging platform where every feature beyond core chat is a plugin you can install or remove, inspired by VS Code's extension model but applied to real-time communication. The Moleculer microservice backend scales horizontally across nodes while Socket.io delivers instant message synchronization with text, images, files, mentions, reactions, and rich Markdown formatting. Available plugins provide LiveKit video conferencing, collaborative drawing boards, task management panels, end-to-end encryption, custom themes, and third-party push notification reception without touching core code. Groups use a two-level space system with customizable panel layouts arranged through drag-and-drop, while role-based access control enforces fine-grained permissions across the organization. The Open Platform exposes OAuth for single sign-on across connected applications and a Bot API enabling bidirectional message processing between Tailchat and external services via HTTP requests. Multi-platform clients cover web, Electron desktop with screenshot capabilities, and mobile apps with native push. Docker Compose deployment bundles MongoDB for persistence, Redis for caching and transport, and MinIO for S3-compatible file storage. Deploy on RepoCloud with a dedicated VPS for persistent team infrastructure under the Apache 2.0 license.

Confluence and Notion both want your team's documentation in their cloud; Docmost, an open-source collaborative wiki platform, keeps it on your server. The centerpiece is a Notion-style block editor with CRDT-based real-time collaboration: multiple people edit the same page simultaneously and changes merge without conflicts or overwrites. Content lives in spaces - per team, project, or department - with nested page trees, role-based permissions, groups, inline comments, page history with restore, and full-text search across everything. The editor covers tables, code blocks, callouts, KaTeX math, and file attachments, and diagramming is built in rather than bolted on: Mermaid, Draw.io, and Excalidraw all render inside pages, alongside embeds for Airtable, Loom, Miro, and more. Migration paths include Notion, Markdown, HTML, and ZIP archive imports (Confluence, PDF, and DOCX importers ship in the Enterprise edition, along with SSO via SAML/OIDC/LDAP and MFA). The stack is TypeScript with PostgreSQL and Redis, deploys via Docker Compose, runs in air-gapped environments with no external dependencies, and is translated into 10+ languages. The AGPL-3.0 community edition carries no per-seat fees; the project has passed 20,000 GitHub stars since its 2024 launch.

Paper co-authors usually trade .tex files by email or pay for a hosted editor seat by seat; Aldine replaces both with a self-hosted LaTeX workspace where the whole team types in one document at once and sees a typeset PDF seconds later. Live cursors and presence show who is editing which paragraph, and the underlying sync is conflict-free, so two authors can rewrite the same section without overwriting each other. Every project is a real git repository: branch a draft, edit it independently, and merge it back from the interface when the argument holds together. Connect GitHub, GitLab, Gitea, or Forgejo to push and pull without leaving the editor, watch ahead and behind indicators, resolve conflicts, and open a pull or merge request on the merged result. Moving in is painless, since an exported Overleaf project ZIP dropped on the home screen imports with its root file detected and its first typeset automatic. Citations come from your own Zotero library or a single collection, kept in sync as a .bib file and inserted from a search panel or \cite autocomplete. Reviewers select text and leave anchored, threaded comments, optionally with a suggested replacement the author accepts in one click. Compiles run in a sandboxed container with no network access, warm recompiles land in about two seconds, and errors jump to the offending line. Running on a dedicated VPS on RepoCloud with guaranteed CPU, RAM, and SSD, full root SSH access, and a browser serial console. AGPL-3.0 licensed.

Somewhere in every organisation there is a folder called FINAL_v2 that nobody dares delete, and Drive from La Suite exists to end that. It gives teams a shared file space where uploads land in organised workspaces, versions stay findable through search, and every file or folder carries its own access list. You preview PDFs, images, audio, and video in the browser, and office documents open for editing through Collabora or OnlyOffice without downloading a thing. Sharing reaches outside the organisation too: invite external partners by link, even without an account, and revoke access the moment a project ends. Uploads pass malware scanning before they touch storage, a trash bin restores accidents, and quotas with usage metrics keep big archives honest. Administrators plug in their own OIDC identity provider, so logins follow the same single sign-on as the rest of the stack, while an embeddable file picker lets other internal apps reuse Drive as their document library. Because the data lives in your own S3-compatible storage, sovereignty requests stop being an argument with a vendor and become a setting. Running on a dedicated VPS on RepoCloud with guaranteed CPU, RAM, and SSD, full root SSH access, and a browser serial console. MIT licensed.

In continuous open-source development since 2009, Etherpad is the original really-real-time collaborative editor - used by Wikimedia, governments, EU public-sector institutions, and tens of thousands of self-hosters. Its core idea is visible authorship: every keystroke is attributed with author colors, every revision preserved, and the timeslider lets you scrub through a document's entire history character by character. Multiple people type into the same pad and see each other's changes instantly - it scales to thousands of simultaneous editors per pad. The base install is deliberately lightweight; capability comes from roughly 290 plugins installable from the admin web UI: comments, images, tables, drawing, video chat via WebRTC, math rendering, code highlighting, and authentication via OAuth, LDAP, or OpenID. AI is pointedly a plugin, not a default - you choose the model and infrastructure, or never turn it on. There is no telemetry. For integrators, an HTTP API (with OpenAPI definitions at /api/openapi.json) manages pads, users, and groups for embedding in your own applications, and the ueberDB abstraction layer supports PostgreSQL, MySQL, Redis, MongoDB, and SQLite backends. Full data export is built in, the format is open, it is translated into 105 languages, and it runs on anything from a Raspberry Pi to a server farm. Apache 2.0 licensed, Node.js based.

SOGo adds shared calendars, address books, and a modern webmail interface to your existing Dovecot, Postfix, or Cyrus mail setup, turning familiar infrastructure into a full Exchange competitor. Rather than replacing your IMAP and SMTP servers, SOGo layers collaboration on top of them, becoming the missing link between raw mail delivery and what users actually expect from a workplace communication platform. The ActiveSync implementation synchronizes email, contacts, calendars, and tasks natively with iPhones, Android devices, and Windows without requiring users to manually configure CalDAV endpoints. CalDAV and CardDAV compliance ensures Apple Calendar, Thunderbird (via the official SOGo Connector extension), GNOME Evolution, and Android via DAVx5 all connect without plugins or workarounds. The web interface uses AngularJS Material design with responsive layouts, offering folder management, drag-and-drop calendar scheduling, contact groups, resource booking, and delegation. Shared calendars support free-busy lookups, iMIP event invitations, and per-user ACL permissions for fine-grained access across organizational units. Built on Objective-C with the GNUstep foundation, SOGo delivers exceptional performance: hundreds of concurrent ActiveSync connections from mobile devices alongside webmail and calendar traffic with sub-second response times. With 2,095+ stars and 116 releases, the project has proven its stability in production environments supporting thousands of users. The Docker deployment runs alongside PostgreSQL and memcached.

Initiative is a self-hosted, multi-tenant project management platform that organizes projects, tasks, collaborative documents, and schedules into strictly isolated community workspaces without enterprise complexity. Users create distinct communities where data remains strictly partitioned across separate database schemas, allowing agencies, volunteer groups, and gaming guilds to manage multiple client environments from a single deployment. Within each community, initiatives group related projects and documents while interactive drag-and-drop Kanban boards track task progression across custom columns, priorities, and deadlines. Integrated collaborative documents enable team members to co-author notes, project briefs, and meeting minutes in real time with threaded inline discussions and user mentions. Granular role-based permissions let administrators specify exact view and edit privileges down to individual items, while a recoverable trash system prevents accidental deletions from interrupting live operations. Curated marketplace apps supply customizable analytics dashboards, and optional bring-your-own-key artificial intelligence integrations generate task suggestions and summarize lengthy discussion threads. Running on a dedicated VPS on RepoCloud with guaranteed CPU, RAM, and SSD, full root SSH access, and a browser serial console. GNU AGPLv3 licensed.

webtrees turns a GEDCOM family file into a private, collaborative genealogy website where relatives anywhere browse ancestors, add photos and sources, and edit together under privacy rules the owner controls. Import a file and each person gets a page of facts, events, and citations, with tabs for families, sources, places, media, and albums and a navigator that jumps to parents, spouses, children, and siblings. Pedigree, fan, hourglass, compact, descendant, interactive, lifespan, relationship, and timeline charts show the same people from different angles, and a pedigree map plots ancestors' birthplaces on OpenStreetMap. Lists sort and filter individuals, families, sources, notes, repositories, and media, with branches that group people by surname. A calendar surfaces births, deaths, marriages, and anniversaries for any day, month, or year, in Gregorian, Julian, Jewish, Hijri, or Jalali dates. Printable PDF reports cover Ahnentafel, family group, descendancy, birth, death, and cemetery records, and search offers general, advanced, and search-and-replace modes for authorized users. Privacy rules apply per site, tree, user, record, and fact, so only authorized users see living people and sensitive details. Editors propose changes, moderators approve them, one site hosts several trees, and the interface comes in more than 60 languages. GEDCOM export lets every tree move to desktop genealogy programs. Running on a dedicated VPS on RepoCloud with guaranteed CPU, RAM, and SSD, full root SSH access, and a browser serial console. GPL-3.0 licensed.

The Bitwarden server, reimplemented in Rust: Vaultwarden (formerly bitwarden_rs) is the unofficial lightweight edition. It speaks the same wire protocol as the official server, so every official Bitwarden client - browser extensions, iOS, Android, desktop, and the bw CLI - connects without modification, while the server itself runs as a single container against SQLite (or MySQL/MariaDB/PostgreSQL) instead of the official multi-container stack that wants gigabytes of RAM. Features Bitwarden gates behind paid tiers ship free: organizations with collections, groups, member roles, and policies; TOTP code storage; file attachments; Bitwarden Send; Emergency Access; event logs; and admin password reset. Two-factor options cover authenticator apps, email, FIDO2 WebAuthn, YubiKey, and Duo, and OIDC-based SSO landed natively in v1.35.0. Zero-knowledge encryption is unchanged - vault data is encrypted client-side and the master password never reaches the server. Attachments and Sends store on local disk or S3-compatible backends, an admin panel manages users and server settings, and backup is copying one data directory. Suited to individuals and teams up to roughly 50 users.

Matrix's flagship client, built by the protocol's creators: Element brings the decentralized open standard for real-time communication to web, desktop, iOS, and Android. Paired with a Matrix homeserver, it delivers Slack-quality team messaging where you own every message, file, encryption key, and byte of metadata. End-to-end encryption is on by default, built on Olm and Megolm - the Double Ratchet algorithm family Signal popularized, extended for large-room scalability and publicly audited by NCC Group. Messages encrypt per-device with cross-signed device verification, so even a compromised server yields nothing readable. Federation is the defining capability: like email, users on different homeservers converse seamlessly, and 30+ bridges connect Matrix rooms to Slack, Discord, WhatsApp, and Telegram, so moving to sovereign infrastructure doesn't sever contact with anyone. Rooms support threads, reactions, file sharing, and voice and video calls via Element Call. The result is digital sovereignty chosen by governments and enterprises across Europe: your data sits on your server in your jurisdiction, portable to any other Matrix host because the protocol is an open standard. Apache-2.0 licensed, with no per-user fees at any scale.

With 6,800 GitHub stars and over a decade of development since its 2014 release, ONLYOFFICE Docs delivers a self-hosted Microsoft Office replacement with pixel-perfect OOXML rendering and real-time collaborative editing supporting both Fast (character-by-character) and Strict (manual save) co-authoring modes. The suite encompasses five full-featured editors — Document Editor for DOCX/ODT/EPUB/HTML, Spreadsheet Editor with 500+ functions and pivot tables, Presentation Editor with animations and transitions, Form Creator for fillable PDF forms with field validation, and PDF Editor for annotation and conversion — all operating within a unified web interface. Format support spans 50+ types including DOCX, XLSX, PPTX, ODT, ODS, ODP, PDF, CSV, RTF, TXT, and Markdown with server-side conversion between any supported pair. The JavaScript plugin API enables extending editor functionality through a marketplace of ready-made plugins for ChatGPT integration, speech-to-text, OCR, Zotero citations, and Thesaurus. Ready-to-use connectors integrate with Nextcloud, ownCloud, Seafile, Moodle, Odoo, Confluence, SharePoint, Alfresco, Liferay, and Chamilo, while WOPI protocol compliance enables integration with any WOPI-compatible platform. JWT authentication secures all API communications between host applications and the document server. Deploy via Docker with a single command or DEB/RPM packages on Ubuntu, Debian, CentOS, or RHEL. Running on a dedicated VPS on RepoCloud with guaranteed CPU, RAM, and SSD, full root SSH access, and a browser serial console. GNU AGPL v3 licensed.

Alexandrie provides a structured knowledge base with an extended Markdown editor, granular per-document permissions, and offline editing through its progressive web app. The CodeMirror 6 editor goes well beyond standard Markdown with colored containers, academic callout blocks, KaTeX math expressions, syntax-highlighted code blocks, footnotes, interactive checkboxes, cards, panels, and a custom snippet system with import and export. Full-text search via the Ctrl+K command center returns instant results with content snippets and relevance ranking across all workspaces. Five permission levels covering None, Read, Write, Admin, and Owner apply per document and per user, while OIDC single sign-on integrates with Google, GitHub, Microsoft, Discord, and any OpenID Connect provider. Documents organize into a hierarchical tree of workspaces, categories, and nested entries with tags, bookmarks, pinned notes, and custom icons. Integrated Kanban boards handle task management within each workspace without switching applications. The PWA installs on any device for full offline editing with seamless sync when connectivity returns. Voice-to-text dictation captures notes hands-free, and one-click ZIP backup exports all documents, files, and settings as a portable archive. Over 2,000 GitHub stars and 41 releases back the project. The Docker Compose stack orchestrates the Nuxt 4 frontend, Go Gin backend, MySQL 8 database, and S3-compatible RustFS object storage. Running on a VPS on RepoCloud with guaranteed CPU, RAM, and SSD, full root SSH access, and a browser serial console. MIT licensed.

Any existing relational database becomes a collaborative, Airtable-style smart spreadsheet under NocoDB. It connects to PostgreSQL, MySQL, MariaDB, SQL Server, or SQLite, introspects the schema - tables, relationships, indexes - and renders it as interactive Grid, Gallery, Kanban, Calendar, and Form views without migrating a single row. Your business data stays in your database; NocoDB keeps only its own metadata (view configs, permissions, webhooks) in a separate store. Every connected table automatically gets REST APIs with Swagger documentation, effectively turning legacy databases into modern backends. The spreadsheet layer adds 20+ field types including formulas, lookups, rollups, links, attachments, and currency, plus sorting, filtering, grouping, and multi-field editing. Views can be locked or shared publicly with password protection, role-based access control scopes permissions per user, and webhooks plus CSV, Excel, and Airtable import round out integration. An ERD view visualizes the schema. Built with Node.js and Vue, deployed via Docker, handling millions of rows.

A budget model, the launch document that explains it, and the slides that present it can live side by side in one self-hosted office workspace that people and AI agents edit together. Personal and Team Spaces organize Sheets, Docs, Slides, relational Bases, and Boards, with Recent, Trash, file import, and export views keeping everyday housekeeping close at hand. Sharing follows role and node aware access control, including anonymous viewing, so a single table or document can be opened to a reader without exposing the whole space. Data and references stay connected across artifacts as the workspace changes, which keeps a figure corrected in a sheet consistent with the document that quotes it. The Workspace Agent drafts and revises content in isolated Worktrees, verifies its own changes, and hands the result to a person for review before anything reaches the trunk. Several review rounds can happen while humans keep editing in the Browser, and nothing merges until someone approves it. The Workspace CLI connects existing agents to your deployment, so automation can create content, inspect data, render screenshots and PDFs, and run layout checks before review. Sign-in accepts passwords, GitHub, Discord, or application OAuth, and files move in and out as XLSX, DOCX, PPTX, and CSV without a separate conversion project. Running on a dedicated VPS on RepoCloud with guaranteed CPU, RAM, and SSD, full root SSH access, and a browser serial console. Apache-2.0 licensed.

An open-source alternative to Notion and Google Docs developed jointly by France's DINUM and Germany's ZenDiS that prioritizes data sovereignty, real-time collaboration, and structured knowledge management. The Yjs-powered CRDT engine provides live cursors, presence indicators, and inline comments enabling teams to edit simultaneously without conflicts, while BlockNote.js renders a clean block-based editing experience with rich text formatting, Markdown shortcuts, and drag-and-drop content organization. Hierarchical sub-documents create wiki-style knowledge bases where documentation nests naturally into navigable structures, and a dedicated slide mode transforms any document into a presentation without separate tooling. The document API separates content from metadata with distinct endpoints for formatted content, raw content streams, and document properties. Optional AI integration connects to configurable language models for writing assistance, summarization, and content generation directly within the editor. Access control supports granular permissions per document with team sharing, public links, and invitation flows. DOCX import brings existing documents into the platform while maintaining formatting fidelity. The Django backend serves a REST API with PostgreSQL storage, Redis caching, and S3-compatible media handling. Deploy via Docker Compose, Kubernetes with the official Helm chart, Nix, or YunoHost on your own infrastructure. Running on a dedicated VPS on RepoCloud with guaranteed CPU, RAM, and SSD, full root SSH access, and a browser serial console. MIT licensed.

Half the architecture sketches on the internet trace back to Excalidraw - the MIT-licensed virtual whiteboard whose hand-drawn aesthetic made technical diagramming feel approachable, at roughly 85,000 GitHub stars. The infinite canvas offers rectangles, ellipses, diamonds, arrows with smart binding and labels, free-draw, text, images, and an eraser, with full undo/redo, zoom, dark mode, and keyboard-first ergonomics. Community shape libraries add thousands of pre-built elements - AWS architecture icons, flowchart stencils, UI wireframe kits - and everything exports to PNG, SVG, the clipboard, or the open .excalidraw JSON format that keeps drawings diffable and portable. Live collaboration works on a share-a-link model with live cursors and a laser pointer for presenting, and it is end-to-end encrypted by design: the room key travels in the URL hash, which never reaches the server, so the WebSocket relay only ever sees ciphertext. The architecture is remarkably light - the app is a static bundle served by Nginx, drawings persist locally in the browser, and the stateless excalidraw-room relay handles multiplayer - so a self-hosted deployment gives unlimited boards and collaborators with near-zero resource cost, replacing per-editor whiteboard subscriptions.

Most wikis die of flat page-and-tag sprawl; BookStack's defining decision is enforced structure - an MIT-licensed PHP/Laravel platform (over MySQL) where content lives in a hierarchy of shelves, books, chapters, and pages, the way a physical library works. A shelf maps to a department, a book to "Engineering Runbooks," a chapter to "Database Procedures," a page to the actual document. That opinionation removes the "where does this go?" friction and keeps knowledge bases tidy as they grow. Editing works both ways: a clean WYSIWYG editor for most users, a Markdown editor with live preview for those who prefer it - switchable per page. Full-text search spans all books or scopes to one, with direct links to individual paragraphs, and include tags let you embed one page's content inside another so shared blocks update everywhere at once. Every edit creates a diffable, revertible revision. Page templates standardize recurring formats, tags add cross-cutting categorization, and built-in diagrams.net integration draws architecture diagrams in place. Authentication covers email/password plus OIDC, SAML2, LDAP, and social login; a full role and permission system locks content down per shelf, book, or page. Pages and books export to PDF, HTML, plain text, and Markdown, a REST API automates content, and the whole thing runs happily on the cheapest VPS you can find.

A Node.js server, a large shared canvas, and a URL - WBO (Whiteboard Ophir) is collaborative whiteboarding reduced to its essence. There are no accounts and no setup - to collaborate, you send someone the board's link, and every stroke appears for all connected users in real time over WebSockets, with cursor positions shared so you can see where collaborators are working. Board state persists automatically and continuously, so a diagram drawn in today's lesson is still there next week at the same URL. Boards come in three flavors: a public free-for-all, private boards with random unguessable names, and named boards with custom URLs shared by anyone who knows the name. The tools cover teaching and brainstorming needs - pencil, straight lines, rectangles, ellipses, text annotations, eraser, a full color palette with brush sizes - and boards export as SVG or PNG. Despite the simplicity, the server is production-minded: JWT authentication gates board access with granular capabilities (open, edit, and clear as separate permissions), rate limiting caps per-client message volume, reverse-proxy and subpath deployment are supported, and OpenTelemetry provides metrics, logs, and traces. It works on tablets and touch devices, speaks multiple languages, and consumes minimal resources. AGPL-licensed.