Best open-source team wiki tools in 2026

If you want a team wiki you can self-host and actually own, you have good options in 2026 — but they differ more than the marketing suggests, and one of them isn't technically open source despite usually being listed as such. This is a fair roundup: real strengths, real trade-offs, and who each tool is genuinely for. Licenses below are verified, because "open source" gets used loosely and the distinction matters for procurement.

A quick note on licenses up front. OSI-approved open source (MIT, AGPL, GPL) means you can self-host, modify, and run it with no rug-pull risk. The Business Source License (BSL) is source-available but not OSI open source — it carries usage restrictions and only converts to an open license on a delay. That difference can be a hard blocker for government and enterprise procurement, so it's worth knowing which is which.

Outline

License: Business Source License 1.1 (source-available, not OSI open source) · Self-host: Yes

Outline is the most polished option here. It feels like a modern SaaS product — fast, clean, great editor, the closest thing to Notion's look in a self-hostable package. If your priority is a wiki your whole company will enjoy using, it's a strong default.

The catch is the license. BSL 1.1 is not OSI-approved open source; it's source-available with usage restrictions, and each release restarts the clock before it converts to a permissive license. For most teams that's fine. For anyone with an open-source mandate or strict procurement rules, it can be a non-starter — so check before you commit.

Who it's for: teams that want the most refined, Notion-like experience and aren't bound by an OSI-license requirement.

BookStack

License: MIT (permissive, OSI open source) · Self-host: Yes

BookStack is the simple, mature, dependable choice. It's a PHP/Laravel app with a deliberately rigid structure — Shelves, Books, Chapters, Pages — that makes content easy to organize and nearly impossible to get lost in. It's been around for years, it's stable, and the MIT license is as permissive as it gets.

The same rigidity is the trade-off: if your knowledge doesn't fit the book/chapter hierarchy, you'll feel the constraints, and it's less flexible and extensible than the others. It prioritizes ease of use over power.

Who it's for: teams that want a clean, low-maintenance knowledge base with zero license worries and don't need deep customization.

Docmost

License: AGPL-3.0 (OSI open source) · Self-host: Yes

Docmost is the modern block-editor entrant, frequently pitched as a self-hostable Notion/Confluence alternative. Real-time collaborative editing, a nice block-based writing experience, spaces and permissions, and an AGPL license that's genuinely open source. It also ships a first-party MCP server, so AI assistants can search, read, and write workspace content — a forward-looking touch most wikis don't offer natively.

It's younger than BookStack or MediaWiki, so the ecosystem and long-tail features are still maturing, and AGPL's copyleft terms are worth understanding if you plan to modify and redistribute it.

Who it's for: teams that want a modern Notion-style block editor, real-time collaboration, and built-in agent access, on a true open-source license.

Wiki.js

License: AGPL-3.0 (OSI open source) · Self-host: Yes

Wiki.js is the flexible, good-looking generalist. It runs on Node.js, supports a wide range of databases (PostgreSQL, MySQL, MariaDB, SQL Server, SQLite), offers multiple editors including Markdown and WikiText, and has broad auth and storage integrations. The current v2 is solid and widely deployed.

The honest caveat is roadmap risk: the v3 rewrite has been in development for years and its beta still has no firm general-availability date as of mid-2026. v2 works well today, but don't pick Wiki.js expecting imminent v3 features.

Who it's for: teams that want a flexible, integration-friendly wiki on open source and are happy running the stable v2.

MediaWiki

License: GPL-2.0 (OSI open source) · Self-host: Yes

MediaWiki is the engine behind Wikipedia, which tells you most of what you need to know: it is battle-tested at a scale nothing else here approaches, infinitely extensible, and capable of running enormous knowledge bases for decades. If you need rock-solid stability and an extension for everything, it delivers.

It's also heavy. The editing experience is dated, the admin and extension model has a real learning curve, and standing it up nicely for a small modern team is more work than the others. You're adopting serious infrastructure, not a lightweight app.

Who it's for: large or long-lived knowledge bases that value durability and extensibility over a modern editing feel.

tela

License: AGPL-3.0 (OSI open source) · Self-host: Yes (plus a free cloud tier)

tela is a markdown-native team wiki built on Go and PostgreSQL, AGPL-licensed and self-hostable, with a free cloud tier if you'd rather not run it yourself. Page content is canonical markdown, it has both full-text and semantic search, and it's built with AI agents as first-class users.

Its distinct angle is two things. First, a built-in MCP server so agents can read and write the wiki directly — note that Docmost (first-party) and BookStack/Wiki.js (community servers) also support MCP, so this is a strength tela shares, not a monopoly. Second, and more genuinely differentiating, Atlas: it auto-generates a cited wiki from your git repos and Jira, linking each generated claim back to the commit or ticket it came from, so you can verify it and see when it drifts. That tackles the staleness problem most wikis leave entirely to human discipline.

It's the newest tool on this list, so it's less battle-tested than MediaWiki or BookStack, and Atlas's generated prose — like any LLM output — should be reviewed, since "cited" means traceable, not guaranteed correct.

Who it's for: engineering teams that live in markdown, want agents as first-class wiki users, and want documentation generated and kept honest against their code and tickets.

How to choose

There's no single winner — the right pick depends on your license constraints, how much polish versus durability you need, and whether agent access and generated documentation matter to your team. All six are real, self-hostable options you can adopt without lock-in (with the BSL caveat noted for Outline).