Gaining over 71,000 GitHub stars as one of the fastest-rising knowledge management platforms, AFFiNE merges the document editing capabilities of Notion, the infinite canvas of Miro, and the structured data of Airtable into a single cohesive workspace. The block-based editor built on the custom BlockSuite framework supports rich text, code blocks, embeds, tables, kanban boards, and database views with drag-and-drop composition. The whiteboard mode provides an infinite canvas where users can freely mix documents, sticky notes, shapes, connectors, and hand-drawn elements, enabling visual thinking alongside structured note-taking. Real-time collaboration allows multiple users to edit documents and whiteboards simultaneously with cursor presence, comment threads, and version history. The local-first architecture stores all data on your device by default using CRDT-based synchronization, ensuring offline access and data sovereignty, with optional cloud sync for cross-device availability. Workspaces organize content into hierarchical page trees with full-text search, favorites, tags, and trash management. The platform supports Markdown import and export, PDF export, and HTML export for interoperability. AI features powered by configurable LLM providers enable writing assistance, summarization, translation, and content generation directly within documents. The theming system supports light and dark modes with customizable accent colors. Running on a dedicated VPS on RepoCloud with guaranteed CPU, RAM, and SSD, full root SSH access, and a browser serial console. Licensed under MIT with an open-source self-hosted edition.

With over 75,000 GitHub stars and native apps across macOS, Windows, Linux, iOS, and Android, AppFlowy is the most widely adopted open-source alternative to Notion — delivering the same block-based workspace model with full data sovereignty. The Flutter frontend renders natively on every platform while a Rust backend powered by Actix-web and Tokio handles CRDT-based real-time collaboration, ensuring sub-second sync across devices with conflict-free concurrent editing. Relational databases support grid, board, kanban, calendar, and gallery views over the same dataset, with two-way relations, rollups, advanced filters, sorts, and formula calculations that cover the majority of Notion's database workflows. The block editor supports 40+ content types including nested pages, toggles, callouts, code blocks with syntax highlighting, embeds, and slash-command insertion. AI integration connects to OpenAI, Anthropic, or local models via Ollama for writing assistance, summarization, and translation — all without sending data off-premises when using on-prem LLMs. Team spaces with workspace-level and per-page permissions, OAuth and SSO authentication through GoTrue, and S3-compatible object storage via MinIO provide enterprise-grade access control and file management. The self-hosted stack deploys through Docker Compose with PostgreSQL for metadata, Redis for caching and pub/sub, and a dedicated background worker for imports and email notifications. Offline-first architecture ensures the desktop app functions without connectivity, syncing changes when the connection resumes. 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.

Scattered browser tabs, buried wiki folders, and disconnected issue trackers fragment engineering context across too many tools, which is why Ideon unifies your repositories, notes, and tasks on a shared infinite canvas. Rather than forcing projects into rigid folder hierarchies, you arrange interactive blocks spatially on a two-dimensional map where related documents, checklists, calendar schedules, and code references sit right beside one another. Teams can embed live repository cards and open issue streams directly from GitHub, GitLab, Gitea, and Forgejo onto the workspace, keeping code status visible alongside architecture documentation. Rich content blocks render Markdown notes with threaded comments, Mermaid flowcharts, uploaded files, images, and bookmarked links on the same board. Real-time multiplayer collaboration lets teammates edit blocks simultaneously, follow live cursors across the canvas, and map system designs together without edit conflicts. Built-in Time Travel snapshots capture historical states of the workspace so you can scrub backward to review how a project evolved or trace past design decisions. You can even synchronize an entire project canvas directly to a Git repository, storing notes and spatial block layouts as versioned files. 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.

A project brief and the task board tracking it belong together, and Litpage keeps pages, databases, and team discussion in one self-hosted workspace instead of scattering them across subscriptions. Write in a block editor with 41 block types, a slash menu, markdown shortcuts, drag and drop, mentions, equations, and highlighted code blocks. The same data becomes a table, board, list, gallery, calendar, timeline, chart, dashboard, feed, form, or map, with typed fields, formulas, relations, and rollups underneath. Automations and buttons turn those databases into working tools, while templates keep repeated projects consistent. Teammates edit together live, comment, suggest edits, and revisit version history, with page-level and field-level permissions deciding who sees what. Pages can be shared publicly or published as sites, and Markdown, CSV, HTML, Word, and PDF files import into the tree. Optional AI runs on the provider and key you configure: chat that searches your workspace, custom agents on schedules or triggers, writing help, database autofill, and meeting-note summaries. Administrators get member and guest management, security policies, an audit log, analytics, passkeys, and two-step verification. A REST API with personal tokens, webhooks, and an MCP endpoint open everything to your other tools. Running on a dedicated VPS on RepoCloud with guaranteed CPU, RAM, and SSD, full root SSH access, and a browser serial console. MIT licensed.

With nearly 5,000 GitHub stars and a Hacker News launch that garnered 147 points, Colanode delivers the first genuinely local-first alternative to both Slack and Notion in a single self-hosted workspace — writing every operation to a client-side SQLite database before syncing to your server, so teams work at full speed offline, on planes, or through intermittent connections without ever losing a draft. The real-time chat system provides channels and direct messages with instant delivery via WebSocket, while the rich text editor offers Notion-style block-based pages for documents, wikis, meeting notes, and knowledge bases with headings, code blocks, embeds, and nested hierarchies. Customizable databases organize structured data with custom fields and three dynamic views — table for spreadsheet-style browsing, kanban for visual workflow boards, and calendar for time-based planning. Conflict-free Replicated Data Types powered by Yjs handle concurrent editing across pages and database records: multiple users modify the same document simultaneously and the system merges changes automatically without manual conflict resolution. File management supports upload, sharing, and organization within workspaces using pluggable storage backends including local filesystem, S3-compatible services, Google Cloud Storage, and Azure Blob Storage with TUS resumable uploads for large files. The server runs Fastify with Zod validation on Node.js 20+, persists to PostgreSQL with pgvector extension, uses Redis for event broadcasting, and deploys via a single Docker image. 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.

From the Mattermost team comes Focalboard, an open-source, MIT-licensed project board tool - a self-hosted alternative to Trello, Asana, and Notion databases, written in Go with a React frontend. Every board renders the same card data four ways: Kanban with drag-and-drop columns, a spreadsheet-style table, an image-forward gallery, and a calendar. Cards carry unlimited custom properties - dates, dropdowns, checkboxes, people, URLs - and boards can be grouped, filtered, and sorted by any property combination, with unlimited saved filtered views for quick access. Built-in templates cover the common workflows (meeting agendas, content calendars, project tasks, roadmaps, sprint planning), or you can build fully custom boards from scratch. Collaboration is real: card comments with @mentions, per-board permissions for teams or individuals, file attachments stored on your own infrastructure, and archiving with backup snapshots. Migration tooling imports existing boards from Trello (JSON export), Asana, and Notion, so switching does not mean starting over. It ships in 20+ languages and runs as a lightweight multi-user personal server. Worth knowing before deploying: Mattermost has shifted primary development to the integrated Mattermost Boards plugin, so the standalone edition is community-maintained - stable and functional, but evolving slowly. For teams wanting a free, private Trello without per-user fees, it remains a solid pick.

An Airtable-style spreadsheet interface directly on PostgreSQL: Teable is an open-source no-code database where every table is a real Postgres table. Unlike tools that store records in a metadata abstraction layer, every Teable table is a real Postgres table with standard column types, so filtering, sorting, and grouping run at database speed, million-row tables answer complex filters in roughly 200 milliseconds without index tuning, and any PostgreSQL-compatible tool - psql, BI dashboards, ETL pipelines - can query the same data directly. The interface offers Grid, Kanban, Gallery, Calendar, and Form views as non-destructive overlays with their own filters and hidden fields, plus 20+ field types, formulas, comments, attachments, batch editing, undo/redo, and edit history. Collaboration is real-time with live cursors and instant sync across views, backed by Redis, and a REST API is auto-generated per table, largely compatible with Airtable API clients - alongside native SQL access for BI tools, analytics pipelines, and your own applications to JOIN and query directly, with no exports, API rate limits, or sync jobs. Global search spans all records, chart plugins handle quick visualization, and CSV and Excel import/export cover migrations. Where Airtable caps paid plans at 100K-500K rows and charges roughly $20 per user per month, a self-hosted Teable instance has neither limit: the Postgres database itself is the export if you ever leave. Built in TypeScript with NestJS, deployed via Docker with PostgreSQL and Redis, and licensed AGPL-3.0.

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.

Excaliself turns the Excalidraw canvas into your team's own whiteboard server, where every sketch, diagram, and flowchart lives in your database instead of a vendor's cloud. The home screen works like a file cabinet for drawings: nest them in folders, star the keepers, drag files between spaces, and find anything again by title or by the text inside the drawing. Share a link and teammates edit together in real time with live cursors and follow mode; links can stay members-only or open to guests who have no account at all. A shared Team space sits next to everyone's private space, and one team library holds the shapes and icons the whole group reuses. AI clients can join with a personal access token: Claude Code or Claude Desktop can search your drawings, read what a diagram says, and create new ones from shapes or a Mermaid flowchart. Accounts are invite-only, single sign-on covers Google, Microsoft, and any OIDC provider, and admins manage members, roles, and password resets from Settings. Deleted drawings rest in a trash folder for thirty days before they are purged, and everything auto-saves as you draw. Running on a dedicated VPS on RepoCloud with guaranteed CPU, RAM, and SSD, full root SSH access, and a browser serial console. MIT licensed.

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.

With 27,000 GitHub stars and 349 releases shipping multiple times per week, Huly replaces four separate SaaS subscriptions — Linear for issue tracking, Notion for documents, Slack for team chat, and Motion for time-blocking — with a single self-hosted platform that charges nothing per seat. The issue tracker provides projects, sprints, roadmaps, custom workflows, and Kanban views with bi-directional GitHub and GitLab synchronization that keeps issues and pull requests in lockstep across both systems. Collaborative documents use CRDT-based real-time editing for wikis, meeting notes, and technical specs with nested page hierarchies and rich embedding. Team messaging delivers channels, direct messages, threaded conversations, reactions, and pinned messages in a Slack-equivalent interface that lives alongside your project context. The time-blocking planner schedules tasks into calendar slots with drag-and-drop, integrating directly with your issue backlog so nothing falls through cracks. A virtual office module provides audio and video rooms for standups and pair programming with external guest access. HR features handle team management, office hours, and PTO tracking. The architecture runs 30+ microservices on CockroachDB for ACID-compliant storage, Elasticsearch for full-text search, MinIO for file attachments, and Redpanda for event streaming. Desktop apps ship for macOS, Windows, and Linux alongside mobile apps for iOS and Android. Running on a dedicated VPS on RepoCloud with guaranteed CPU, RAM, and SSD, full root SSH access, and a browser serial console. EPL-2.0 licensed.

Doca puts rich text, Markdown, spreadsheets, slides, and an infinite canvas under one login and one permission model, giving individuals and small teams a self-hosted workspace for writing together. Every format supports real-time co-editing with presence, comments, saved history, and manual snapshots, and rich text and Markdown documents can be restored to an earlier version. Documents live in knowledge libraries with tree navigation, invitations, inherited permissions, share links, and trash, while personal files and shared folders sit on local disk or S3-compatible storage. Knowledge books go further: they subscribe to sources, run an editable workflow, keep source evidence, and route results through human review. A personal AI assistant, powered by whichever model you configure, searches authorized documents, reads PDF and Office attachments, edits images, and prepares browser drafts. MCP services let external AI clients such as Codex use those tools under your permissions. Sign in with a password, OIDC, Google, GitHub, WeChat, or QQ, review registrations before they go live, and send webhooks to other systems. A plugin SDK and marketplace add business modules, and a browser extension clips pages into documents. The interface ships in Chinese and English. Running on a dedicated VPS on RepoCloud with guaranteed CPU, RAM, and SSD, full root SSH access, and a browser serial console. MIT licensed.