Growing the MediaWiki Technical Community

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Related Phabricator Task T183318
Topic Leaders Birgit Müller, Matthew Flaschen

11 primary statements. 3 secondary statements.


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  • Architecture
  • Artificial Intelligence
  • Code Review
  • Collaboration
  • Communication
  • Communities
  • Complexity
  • Documentation
  • Drupal
  • Gadgets
  • Innovation
  • Installation
  • JavaScript
  • Lua
  • Open Source
  • OpenStreetMap
  • Refactoring
  • Retention
  • Security
  • Software Development Practices
  • Technical Debt
  • Templates
  • Testing
  • Third Parties
  • Tools
  • Volunteer Developers
  • Wikibase
  • Wikidata
  • WordPress

Primary

Author Tags Primary Session Secondary Sessions Position Statement
Katie Horn Third Parties, Volunteer Developers Growing the MediaWiki Technical Community

WMF should focus on the technical issues it is uniquely positioned to handle, and let the volunteers have the fun stuff.

When we think about what technical work the WMF is engaging in, I don't believe enough time is spent considering volunteer motivation, and the great potential we are systematically choosing to ignore, or end up devaluing entirely due to the inherent unpredictability of volunteer work. I do believe that there is a long enough history of deeply understaffed WMF engineering teams getting set up to tackle fancy front-facing projects, only to have those teams simultaneously struggle to deliver, and deter everyone else from getting too near decision-making in their territory. It is time to change our approach.

I would like to talk about what it would take, to refocus the majority of WMF's technical work away from taking full ownership of all the 'important' new ideas, and toward making it as easy as possible for momentarily highly motivated outside parties to make meaningful contributions to new features. I imagine many new tools would be required to scale release engineering, security, and the technical community in general. We would have to take a greater role in mentoring interested parties. There are also known big hairy unsolved problems in the way we currently think of maintainership. Major changes would have to be made in our current approach to product timelines and product/project management.

Of course, there will always be things that do require a high level of predictability in the outcomes. Donor money can and should be spent on ensuring predictability around the things we absolutely cannot function without. However, there is a whole world of ideas that absolutely do not have to be accomplished on a strict 'shipping' timeline, and it seems that the WMF will always hold the keys to that door. I would like to figure out how the WMF could start embracing that unpredictability at every level, and move much more deliberately from 'bottleneck' to 'enabler'.

Melody Kramer Communication, Communities, Retention, Volunteer Developers Growing the MediaWiki Technical Community

How do we maintain and grow the technical community and ready it for the mission ahead? Maintaining and growing a technical community is difficult, particularly when the majority of that community is contributing their time and code on a volunteer basis. However, we can look at other successful projects for guidance, to see what we can learn and apply to our own movement: Clearly articulating the value for participants. It's important that we articulate what participants will get (socially, professionally, personally) from contributing to our projects, and it's important to socialize that value through feedback loops, communication, and positive reinforcement. One of my favorite projects - the Smithsonian Transcription Project - hired a full-time community manager for their volunteer community. It was her role to pair participants with projects, follow up to ensure things were going well, and intervene if changes needed to be made. Creating feedback loops that reinforce the value for participants. It's not enough to get people in the door; we must continually reinforce why participation is meaningful for both participants and the mission of free and open knowledge. People will have different reasons for participating - some want to build a skilset, others want to contribute to a meaningful project, still others are completely an assignment. The value for all of these participants differs, and the messaging/communication should reflect that. Finding pathways to participants through non-technical means. GitHub does it particularly well. They want to reach students. So they have a space - https://education.github.com/ - aimed at teachers. This is a particularly smart strategy: How do we reach participants where they are, and think about conduits who might identify possible participants?

  1. 100WikiCodeDays: The project #100WikiDays is successful because it creates a habit for participants, gives them ample feedback, provides them with community support, and gives them a goal. Are there similar efforts that we could think about re: code contributions?

Continually communicate the value: The best open source projects continually communicate to participants and the larger world about what's happening. Someone files their first bug report? Great, maybe they get an email saying 'Here's the next step you can take.' Someone creates a tool for Tool Lab? It's amazing? Send them to the blog for a profile. Let's elevate their work and use it to bring others in.

Leszek Manicki JavaScript Growing the MediaWiki Technical Community Supporting Third-Party Use of MediaWiki

Dependency management for JavaScript packages

I believe we should be using a dependency management tool for JavaScript libraries in MediaWiki.

Currently there is no convenient way to manage JavaScript packages in MediaWiki, even though MediaWiki itself, as well as many extensions widely use them (both "own" JavaScript libraries and third-party libraries). Lack of such a solution in our infrastructure leads to numerous issues. Libraries are duplicated in our code bases, and there is a little control of what version of the package is used by different components. Updating dependencies becomes a complex and error-prone manual process. As each of our components include their dependencies separately, our users might be loading the same package multiple times.

Having a dependency management system for JavaScript packages would be beneficial in multiple areas. Developers would be able to easily control and maintain packages their software depends on. Deploying MediaWiki and extensions would become easier and more transparent with regard to JavaScript packages, both for WMF infrastructure and for non-WMF users of our software. With de-duplication of dependencies, users will be served smaller amount of bytes. Finally, once we have a convenient and standardized way of managing JavaScript packages, our software would be more interesting and welcoming for new developers coming from the dynamically growing JavaScript community.

We have addressed the similar problem for PHP libraries a while ago when we started to use Composer for PHP dependency management. We have been discussing solutions for JavaScript packages for a couple of years. Possible tools like npm, yarn, or even Composer, have been discussed, but we haven't come up with a plausible solution yet.

I hope the summit will be able to collect our requirements, re-evaluate the previous investigations we have made, collect new ideas, and will come up with a solution for JavaScript dependency management. I believe once we have it we will be walking into the future with confidence.

Kunal Mehta Code Review, Volunteer Developers Growing the MediaWiki Technical Community Supporting Third-Party Use of MediaWiki

We have well established that volunteers are the lifeblood of the Wikimedia movement. We prioritize their contributions and work to ensure they are given the tools they need to succeed. But in the Wikimedia development community, we've neglected volunteers instead of nurturing them - and this is a serious problem that we need to rectify. There are a lot of areas where we can improve, but I'm going to focus on just one: improving the volunteer developer's code review experience.

While Wikimedia Foundation product teams are building new things, it's usually the volunteers who are keeping critical tools that the community depends upon alive (AbuseFilter, CheckUser, etc.). The MediaWiki codebase has gotten so massive that it's not practical to try and have the Wikimedia Foundation attempt to maintain all of it. It would not be a good use of movement funds either. Instead, I'm proposing that we utilize our volunteer base and ensure they are the valued and respected members of the Wikimedia development community. I think we can do it in three steps: first, set reasonable standards for code and the review process, second, prioritize code review of patches coming from volunteers, and finally empower volunteers to be maintainers and owners of code and create a sustainable community.

1. Set Reasonable Standards for Code and the Review Process

The status quo is that depending on who reviews your code, you will have a wildly different experience. Some will mandate that principles like dependency injection are followed or others will require 100% test coverage. And others might not care for any of that and just ensure the code does what it is supposed to before merging. But the people who face the worst of it are volunteers - WMF staff will have consistent reviewers through teammates who already communicated standards for merging code.

So we need reasonable standards for code we accept, and use those throughout the review process. As an example of 'reasonable', if someone is trying to fix a bug in legacy code that is difficult to test, it would be unreasonable to mandate a test case before merging the fix.

2. Prioritize code review of patches coming from volunteers

Our current process of reviewing volunteers' patches after finishing code review for teammates isn't working - we have a giant pile of unreviewed patches. When you start your day and look through your list of reviews, pick one or two patches from a volunteer and review them first. Most likely it'll take minimal time, but for previously-neglected volunteers, it will make a big difference.

3. Empower volunteers to be maintainers and owners of code

Some of our volunteers have been around for quite a while and are well trusted. Let's give them +2 rights! There's nothing that makes you feel better than getting an email from someone telling you that your contributions are valued and they'd like to nominate you for +2 access (exactly how I got hooked). And quite a few years I'm still around, so it must have worked.

Birgit Müller Code Review, Collaboration, Communities, Documentation, Gadgets, Open Source, Refactoring, Tools Growing the MediaWiki Technical Community Evolving the MediaWiki Architecture

Refactoring the Open: First steps to get ready for the next level

Wikimedia's technical environment has grown into a very complex system throughout the past 15 years. Measured in internet years, parts of the software are ancient. When implementing a new feature, refactoring of a piece of the (extended) MediaWiki software is often required first. Following this principle of a.) refactoring and b.) implementation of something new, I suggest to start the discussion of the future technology direction by reflecting (and possibly: refactoring) the current Open Source practices and processes within the Wikimedia context.

A mono perspective won't let us survive (and is less fun, too)

When we talk about "Open Source" within Wikimedia we're not only talking about free licenses and open code repositories. We're talking about global collaboration and the technical contributions of many: Through this, we ensure that the Wikimedia projects stay alive and evolve, that we constantly develop new ideas, that multiple and diverse perspectives shape the development of our infrastructure and tools.

We are great in having ideas, and we are good in trying things out. But we still partly fail at prioritising the problems we know we have and address them accordingly.

I believe that we should

better maintain the Technical Community and find ways to grow by

  • allocating stable code review resources from paid staff for volunteer and 3rd party developers
  • improving the documentation of the code base
  • providing a single entry point that is easy accessible for interested developers
  • building up partnerships with Open Source communities we might share interests in the future with (for example, communities around audio, video or translation technologies)

constantly take diverse perspectives into account by

  • finding better ways to gather and address feedback from smaller language communities and non-Wikipedia sites
  • being less Wikipedia-centric when it comes to research: Not yet existing or emerging communities might not be interested in creating articles, but in contributing data or multimedia content or in building tools to reuse data and multimedia content

build more bridges across local wikis and increase knowledge of local requirements by

  • fostering cross-wiki exchange (example activity: template Hackathon)
  • increasing the knowledge of the requirements that come along with different languages (example activity: multilingual support conference)

Open Source doesn't mean anything is possible - does it?

We have established processes and regulations for contributions to MediaWiki itself. But we lack processes and practices for local developments to ensure both, the freedom and space to experiment for the Technical Community and the stability and reliability of tools for users.

I believe that we should e.g.

  • raise priority for implementing a code review process for JS/CSS pages on Wikimedia sites
  • start thinking about a technical sysop user right
  • make it clear which user scripts/gadgets/tools are maintained, which are stable and which are proofs of concept or prototypes (for example: provide a (central) 'store' of maintained gadgets/tools with different levels: "stable version", "experimental version" ...)

Let's start refactoring.

Sam Reed Documentation, Security, Testing Growing the MediaWiki Technical Community

Security is important. Although Wikimedia/MediaWiki has a generally good track record, we should always be striving for better, ideally, in an automated fashion via testing of the code, and providing a decent and easy to use framework inside MediaWiki to allow people to do this without causing them excess work or effort. In some cases, we can do this through documentation; we have some options that allow for complex things to be done, but it's not very clear to developers that what they are doing may lead to security issues down the road.

In the same way we run phpcs, and are moving towards running phan, it would be very nice to improve our automated testing with a security focus. Helping point people to potential pain points in the future, or just general bad practices now.

As Tim Starling said a few years ago, people shouldn't be doing CR for code style etc. It doesn't make sense, it's a waste of time. This should be automated away as much as possible. Which is happening, slowly improving the MediaWiki codebase.

How can we use this basic idea, and improve the MediaWiki software and it's extensions for security best practices?

Moritz Schubotz Artificial Intelligence, Code Review, Testing, Volunteer Developers Growing the MediaWiki Technical Community

Title Developing software in a wiki way

Background Over the last 15 years, MediaWiki evolved from a simple PHP script to a complex and highly integrated family of products and services, serving knowledge to billions of humans. Every change might cause an instability or a complete failure of the system. Thus, measures including code review, automated unit testing and code/ product ownership, have been established to guarantee the stability of the software. The drawback of this approach is that improving the software became very challenging for volunteer contributors. This proposal seeks to lower the barriers for volunteer contributors while maintaining the stability of the system.

Advice (1) Reduce the effort of code review by applying Artificial Intelligence methods. Thus, reviewers can focus on non-formal comments. (2) Develop a dialog platform that ensures that volunteer contributors are aware of the next steps and the roadmap for their change on the way to production. (3) Establish a team that supports volunteer developers, who want to make a difference that is not listed in the annual plan by providing temporary code or product ownership. (4) Improve testing and evaluation to measure the effect of every single change and to identify code or even whole services that are no longer neccary and can be switched off.

Max Semenik Technical Debt Growing the MediaWiki Technical Community

I'm highly interested in having a deep discussion about our technical debt. I've been active in operating on this front myself and I really care how we fare in this aspect, however I see a lack of consensus on tech debt from the development community at large.

We deprecate things and then continue using them. People get irritated when their extensions break due to slightest core changes, even when the extensions themselves are misusing the core interfaces. We can't really run lots of types of static analysis against our code base because the sheer amount of problems detected would make the signal to noise ratio unacceptable. Developing skins for MediaWiki is incredibly painful. Our tests access database a lot, as a result they're slow and fragile. These are just a few examples of pain points haunting our code base and extracting their daily toll from everyone working on it.

I would like to have Tech Debt SIG work in person on addressing these issues. We should define code quality metrics, identify problem areas and create some actionables to address them. We should also discuss approaches to handling this without causing too much discontent from broader developer community.

I believe this would be an important step towards making MediaWiki a better ecosystem and improve our development pace.

Adam Shorland Architecture, Open Source, Wikibase Growing the MediaWiki Technical Community Embracing Open Source Software

I believe that the technicaly community should strive to collect and effectively disseminate technical knowledge as per the Wikimedia missions attement.

Ability to grow out technical community can be compared with ones own ability to gain knowledge in technical spaces within the Wikimedia movement. Currently there are many barriers to entry that have been surfaced year after year with some but little movement forward past them.

To scale and ready the community we should push forward and enable the use of emerging trends in technology, such as knowledge retaining Q&A platforms. There are many other organizations and softwares that do this much better than Wikimedia we should learn from them. Looking at Q&A platforms specifically, talk pages have never really been a good place to ask questions and retain knowledge in a searchable way for use in the future. Stackoverfolw, as an example, has proven to be an invaluable resource for people in technical spaces and we can learn from that. MediaWiki is an amazing piece of software, but we should not feel 'boxed in' by it. The Wikimedia foundation is not the MediaWiki foundation, MediaWiki does not have to always just be a wiki page.

Our commitment to Open Source is often something that slows down many actions within the movement, however this is not something that should change as it is integral to what Wikimedia stands for at the core. We should embrace our Open Source commitments and reach out to and engage with organizations using our software more. Wikimedia Germany does this outreach specifically with the Wikibase extension, looking for other users and engaging them to discover how they are using it, why, and how it can be better. The Wikibase extension also specifically the Wikibase Query Service shows us that not everything has to be a wiki page, as the query service disseminates knowledge under a free licence effectively.

I hope that the summit will agree that entry to our technical space, and increasing knowledge persistence within our technical space needs some thought and work, and that we should stay committed to Mediawiki as a software and platform, but that it can look, feel and act different while Wikimedia stays true to its mission.

Raimond Spekking Lua, OpenStreetMap, Wikidata Growing the MediaWiki Technical Community Knowledge as a Service

tl;dr: Empower more Wikipedians [1] in using Lua, incl. invoking data from Wikidata, and data from the Data namespace on Commons.

In the past 15 years it was relatively easy for every Wikipedian to create templates, and with the ParserFunctions to write some kind of simple program code.

In 2013 we got Lua as real and powerful programming language. Since a short time it is possible to invoke data from Wikidata and a very short time to store/read data in/from the Data namespace on Wikimedia Commons.

These are all good improvements and increases the possibilities in adding valuable data/information to the (often) high quality content of the German Wikipedia. But these techniques increases the requirements in technical knowledge to the Wikipedians. In other words: Substantial less Wikipedians are able to write Lua module than creating templates.

As an active community member of the German Wikipedia and Wikimedia Commons (and Wikidata) I see a real bottleneck in the situation, that we do not have enough Wikipedians with skills in Lua and the possibitiy how to invoke data from Wikidata & Co.

Checking the Module namespace via RecentChanges for September 2017 on the German Wikipedia: Only 13 Wikipedians contributed to Lua code. Often I read on the Village Pump and related pages: "Sorry, but my to-do-list as volunteer is full until end of the year, I do not have the capacity to solve your problem." and so on. This is very frustrating for all sides.

Other cool [3] projects, like integration of Maps via Kartographer, stucks because the German Wikipedia has not enough man power for these works

As a result of this notice we have to create some help to empower more Wikipedians in using Lua, incl. invoking data from Wikidata, and data from the Data namespace on Commons.

In Germany, Austria, and Switzerland it probably easier than in other countries because we can offer real-live workshops. In 2018 the team of the "Wikipedia:Lokal K" [2], a real-live supporting base for Wikipedia & Co, is planning, with the support of WMDE, some workshops for Wikidata. Same could be done for supporting Lua & Co.

As originator of the "Technical Wishlist" [4] I am thinking about adding support for Lua modules & Co to the wishlist.

On the summit I would like to discuss these and other solutions for this bottleneck.


[1] to be read as users of all sister projects

[2] https://de.wikipedia.org/wiki/Wikipedia:Lokal_K

[3] My POV as active OpenStreetMap community member

[4] https://meta.wikimedia.org/wiki/Community_Tech/Community_Wishlist_Survey_description

   Originated by me in September 2013: https://de.wikipedia.org/wiki/Wikipedia:Technische_W%C3%BCnsche/%C3%9Cber_das_Projekt
Tim Starling Architecture, Complexity, Refactoring Growing the MediaWiki Technical Community

A key question for me is how we can maximise the richness of our feature offering despite having entered a period of slow growth in revenue and staff numbers. Wikimedia serves a very large number of users, with a diverse set of needs -- nobody can say that the site as it stands is sufficient to satisfy all of them.

There are two main threats to our goal of providing a rich feature set. One is maintenance burden. We are faced with the prospect of sunsetting features because we find the maintenance burden to be too great. But there is no incontrovertible rule in software engineering which says that code, once written, must constantly be rewritten. Maintenance burden most commonly arises from changes in the platform on which the code is implemented. Minimising maintenance burden for a given feature set thus necessitates choosing a stable platform. We need to consider the programming languages we use, and the libraries we require, through this lens.

The second threat is needless complexity. Concepts which are hard to understand, and which thus restrict related development to highly skilled developers, are appropriate only if hidden behind a module boundary. In order to enable contributions from developers less skilled than ourselves, and to minimise the time required for learning and familiarisation, the bulk of our code should be simple. Complexity is alluring because it provides developers the opportunity to take pride in their work. But for the benefit of the organisation as whole, its efficiency, and thus the richness of its product offering, we should introduce complexity only with due caution.

Code which is complex but stable can be valuable, presenting no great risks. For example, the diff algorithm we currently use in wikidiff2 has its origin in Perl code written in approximately 1998. Only in the last year have we considered adding substantial features to it. We have a PHP port and a C++ port, and neither requires significant maintenance. This is because the requirements are stable and the two respective platforms (C++ and PHP) are stable.

Contrast this to OCG, which is at risk of sunsetting only three years after its original deployment. The reason is that its input and output formats are constantly changing, that is, it has changing requirements; and it was written on a modern and rapidly changing platform. Its main developer wrote "the architecture which was state-of-the-art in 2014 is already looking a little dated in 2016".

My goals for the developer summit are to encourage people to think carefully about writing code on top of a conceptually complex, rapidly changing platform. I want WMF and the MediaWiki community to write code which is stable and long-lasting, and can thus support a richly featured website into the future.

Secondary

Author Tags Primary Session Secondary Sessions Position Statement
Cindy Cicalese Innovation, Installation, Open Source, Third Parties Supporting Third-Party Use of MediaWiki Evolving the MediaWiki Architecture, Growing the MediaWiki Technical Community

How and with whom should we partner to create the technologies needed to support the mission?

A substantial, growing community of MediaWiki users and developers outside the Wikimedia movement has evolved, creating wikis that vary in size, number of editors, number of readers, access restrictions, and activity. The Wikimedia movement benefits from this third party MediaWiki developer and user community's technology contributions and innovation. Similarly, this community benefits from the Wikimedia movement's stewardship of MediaWiki as the foundational technology in support of Wikipedia and its sister projects. There are many areas in which the needs of these two groups are identical, including stable, well-performing software that supports community authoring. Partnering with the third party MediaWiki community will result in a platform that is better for all parties.

How should MediaWiki evolve to support the mission?

There is much knowledge in the world that cannot find its place within Wikipedia or its sister projects. MediaWiki is powerful software crafted especially to support the expression of all knowledge. Third party MediaWiki wikis can provide a home for knowledge that does not belong in Wikipedia, supporting the mission of sharing in the sum of all knowledge. In order for the third party MediaWiki community to continue to thrive and to grow, several impediments to MediaWiki adoption that especially affect that community must be addressed:

- Installing and maintaining all but the smallest and most basic MediaWiki installation currently requires a high level of craftsmanship and expertise.

- While a large number of novel MediaWiki extensions exist to support third party applications, it is difficult to ascertain the level of maturity and support of these extensions.

- Some enterprise consumers require a guaranteed level of support and/or service level agreements before adopting a technology.

- The barrier to entry for those wishing to experiment with MediaWiki in production quality environments is high.

How do we maintain and grow the technical community and ready it for the mission ahead?

The third party MediaWiki community already significantly contributes to the code base. In the last two years, 22% of the commits to MediaWiki core were made by third party contributors, and 62% of the authors of commits to MediaWiki core were third party contributors. Even more striking, in the last two years, 40% of the commits to MediaWiki extensions hosted on gerrit were made by third party contributors, and 67% of the authors of the commits were third party contributors. The third party MediaWiki community is a significant training ground for skilled MediaWiki developers used to tackling a diverse set of challenging problems who sit poised to help forge the path ahead for MediaWiki.

Markus Glaser Code Review, Documentation, Gadgets, Software Development Practices, Templates, Third Parties Supporting Third-Party Use of MediaWiki Growing the MediaWiki Technical Community

Mediawiki needs a professional ecosystem

There is a huge potential for MediaWiki development outside of the Foundation's organized tech world. Thousands of organisations are running MediaWiki on the internet or intranet. They are investing time and money to make it their platform for information sharing, knowledge management or collaborative work. Yet, a lot of the development and design work stays contained on those installations instead of being published and provided to the greater MediaWiki community. I think this is not because of seclusiveness of the authors, but because we make it hard for externals to contribute.

So how can we tap into this potential? I think there are a number of measures we can take. Among others, these are:

  • Support standard ways for code contribution. For example, a lot of developers do have a github account, and know the github workflow of forking and requesting pulls. However, there is currently no way for them to contribute their code directly, instead they have to set up with our gerrit infrastructure. This is a hurdle many will not take.
  • Maintain extensions as a community. There are a lot of extensions which are not actively maintained by their authors. In order to get them working, you have to wait for the maintainer to +2 your code. Although I have +2 rights, it is not clear under which circumstances I should actually +2 code, nor is there a general review queue for extensions. We can establish a group of volunteers who review changes to extensions on a regular basis.
  • Create a template and gadget repository. A lot of work goes into site customisation using gadgets, templates or on-site-CSS. There are brilliant solutions out there, but we do not have a structured way to centrally collect this content or even curate it.
  • Make it attractive for professional developers and consultants build their projects on top of MediaWiki. For example by increasing the visibility of highly used extensions on MediaWiki.org, by providing good entry points for technical documentation or by adding automated quality checks to the extensions.

There are already some initiatives pursuing the general goal of fostering an ecosystem, e.g. MediaWiki Stakeholders or the recently announced Enterprise MediaWiki Consortium. Together with the Foundation, they can encourage MediaWiki maintainers to contribute their ideas and code and be part of the MediaWiki world.

Sam Wilson Drupal, OpenStreetMap, Third Parties, Volunteer Developers, WordPress Supporting Third-Party Use of MediaWiki Growing the MediaWiki Technical Community

tldr: Encourage use of MediaWiki outside WMF projects, because does so furthers the mission (and improves the software).

MediaWiki is primarily a tool that helps the Wikimedia movement. The movement is not primarily about MediaWiki, but MediaWiki is the central tool with which we are currently fulfilling our mission. Lots of other people use MediaWiki too, but their needs are not the focus of WMF development. I think we should do more to encourage 3rd party use of MediaWiki, and in doing so broaden the developer community and end up with higher-quality software that is easier to use for more people.

Our mission is about empowerment and education, and people running their own wikis should be seen as part of that. Just because content isn't hosted on WMF servers doesn't mean it's not part of the movement. I imagine a future in which MediaWiki is as common for collaborative websites as WordPress is for blogs, and people don't have to rely on Facebook, YouTube, GitHub, etc. to host their content.

A couple of parallels (sort of):

  • OpenStreetMap hosts the central database of their map, but they actively discourage people doing anything other than editing on the OSM infrastructure. Instead, there is a large ecosystem of tools and systems for serving that data. This is mainly because it would be impossible for OSM to provide the bandwidth and required formats etc. for all the possible uses - similarly, the set of Wikimedia sister projects are never going to provide every wiki that people want.
  • Automattic runs wordpress.com and also manages the opensource development of WordPress; the latter seemingly in conflict with the former, but because of the long history (and relative late-starting of wordpress.com perhaps) the software has remained a favorite of self-hosted websites. (I'm ignoring the obvious security arguments for a now.)

One reason that MediaWiki is not better for 3rd party users could be that there are not all that many non-WMF people making a living out of developing for it, at least not in comparison with other web frameworks (Drupal, WordPress, etc.). WordPress had to be easy to install on cheap web hosts because that's all there was; MediaWiki seems these days to only have that characteristic as a historical hangover, and it could well end up moving away from being aimed at amateur sysadmins all together.

Perhaps there's a fundamental clash between the scale requirements of the WMF sites vs. the ease-of-administration requirements of 3rd party wikis - but if there's a choice to be made, it should be explicit and well-communicated. At the moment, it feels like it's happening by attrition.