Open Source Wiki Engine

Open source wiki engines, in general, tend to be closer to Ward Cunningham’s key ideas, introduced in WikiWikiWeb . As such, many of them tend to embrace the tenets of minimal secrecy, uniform addressability, and flat namespace to a better degree than the proprietary alternatives.

Some of the most popular open source wiki engines include:

Name	Native Document Format	DocOps Automation
DokuWiki	DokuWiki markup	plug-in SDK (PHP), direct file system interaction with markdown files.
MediaWiki	MediaWiki markup	extensions (PHP), REST APIs, and direct interaction with its MySQL database.
Wiki.js	AsciiDoc (limited support), Markdown (CommonMark + GFM), HTML (to support content imported from legacy systems)	GraphQL API, custom modules (JavaScript)
Twiki	TWiki markup	Proprietary SQL-like query language
XWiki	XWiki markup	scripting (Groovy), Velocity templates, extension points (Java)

DocOps Automation

Open source wiki engines, together with static site generators, are among the most DocOps-friendly documentation platforms. All of the documentation system facets (UI, templating, document loading, etc.) are under the DocOps engineer’s control.

In addition, the database management system is directly accessible by the DocOps engineer which makes it easier to read, create, and update documentation in bulk without the hassle of—potentially—clunky APIs which operate on one document at a time.

Limitations

While open source wiki engines excel in their ability to accommodate DocOps use cases, they—unfortunately—suffer from a number of weaknesses as far as the needs of the large enterprise are concerned:

Authoring delight is often a problem. The text editing experience is often a far cry from What You See Is What You Get (WYSIWYG). Even when it comes to the preferences of ‘rockstar geeks’ (who prefer source-level editing), most open source wiki engines still rely on clunky wiki markup formats rather than the more contemporary Markdown.
The tenets of connected content and embedding and blending are only relevant for content created within the wiki engine itself. The commercial alternatives often have syntax and plug-ins to connect, embed (but not necessarily ‘blend’) content from a variety of 3rd party sources.
Many enterprises have a preference for a pure Software as a Service (SaaS) model. The need to self-host (allocate a VM, install, maintain, patch, etc) software is a significant deterrent in spite of the software itself being ‘free’.