Wabbajack: An Automated Modlist Installer That Ships No Mods

The Installer Ships a List, Not the Mods

Wabbajack is an automated Modlist Installer that can reproduce an entire modding setup on another machine without bundling any assets or re-distributing any mods.

That sentence is the whole architecture, and it is a deliberate legal and technical choice. The tool does not carry a copy of the mods in a modlist. It carries the description of the setup, and at install time it fetches each piece from wherever that piece lives.

The consequences run in both directions. A user gets a working configuration rather than a folder of archives, and the install is a fresh download rather than a copy of somebody else's cache. And a mod author keeps their distribution where it was, with the Nexus, rather than having their work mirrored in a third party archive that the author does not control.

The README is blunt about the second point. Everyone who has access to the Nexus can download your mod, and the Nexus does not and can not lock out Wabbajack from using the API to download a specific mod based on author preferences. So inclusion in a modlist is not a distribution channel that the author can revoke, and the project treats that as a fact rather than an abuse.

The FAQ Answers the Questions Mod Authors Ask First

The FAQ section of the README is worth reading on its own, because it is unusually direct about the rules.

The first question is whether you can charge for a Wabbajack Modlist you created, and the answer is no, as specified in the licence, Wabbajack Modlists must be available for free. Any payment in exchange for access to a Wabbajack installer is strictly prohibited, and the listed examples are paywalling, pay for beta access, and pay for the current version with the previous version free, or any other sort of quid pro quo monetization structure. The team reserves the right to implement software that will prohibit the installation of any lists that are paywalled.

The second question is whether you can accept donations for the installer, and the answer is yes, as long as the act of donating does not entitle the donator to access to the installer. The installer must be free, and donations must be a thank you, not a purchase of services or content.

Those two answers together are the distinction the project is drawing. Free access to the tool and to the modlists, and money allowed in exchange for nothing that unlocks the tool. The FAQ also asks how Wabbajack differs from Automaton, where the author explains that they used to develop on Automaton, that development was moving too slowly, that a complete rewrite would allow features like BSA packing, and that the motto when coding is make it work, then make it pretty.

The Nexus API and the Download Count Argument

The most useful section for a mod author is the one explaining how downloads happen.

Wabbajack uses the official Nexus API to retrieve download links from the Nexus, and mod managers such as MO2 or Vortex also use this API to download files. Downloading using the API is the same as downloading directly from the website, and both increase your download count and give you donation points.

So the answer to the implied question, which is whether inclusion in a modlist helps or hurts, is that it behaves like a user downloading the file, and the metrics reflect it. That reframes inclusion from an act of redistribution to an act of discovery, which is exactly what the FAQ says happens.

The second half of that section addresses opt-out directly. The explanation is that everyone with Nexus access can download the mod anyway, and the Nexus cannot lock out Wabbajack from the API based on author preferences. There is no opt-out mechanism, and the project is candid about the reason rather than pretending the question does not arise.

The Manifest and the Slideshow Make Mods Visible

The next question is whether the end user knows their mod is in the list, and the answer describes two mechanisms.

The first is the manifest. Before the installation even starts, the user has access to the manifest of the Modlist, which contains a list of all the mods to be installed along with the authors, version, size, links and more meta data depending on origin.

The second is the slideshow. Wabbajack starts a Slideshow during the installation which features all the mods to be installed in random order, and the Slideshow displays the title, author, main image, description, version and a link to the Nexus page.

The random order is the interesting part, because it prevents the slideshow from becoming a list of the biggest names first. The rest of the answer covers the case where a mod needs configuration. After installation the user most likely needs to check the instructions of the Modlist for recommended MCM options, and if a mod has an MCM and needs a lot of configuring then it will likely be featured in the instructions, and the project strongly encourages new Modlist Authors to add a section about important mods to their README in the post-compilation step.

Fetching From Sites With No API at All

The last of the mod author questions covers the awkward case, which is a mod that is not on the Nexus.

You can check the list of sites Wabbajack can download from, and the project says it can easily add support for other sites. As long as the mod is publicly accessible and available on the Internet, Wabbajack can probably download it. And the remarkable sentence follows: even if the site requires a login and does not have an API, we can always just resort to our internal browser and download the mod as if a user would go to the website using Firefox or Chrome and click the download button.

So there are three tiers of source. An API, which is the fast and clean path, a site without an API, which the project adds support for, and a site that needs a login and has no API, which is handled by driving a real browser as a user would. The last tier is the slowest and the most fragile.

The tool's own project structure shows the same shape. The downloaders are split by source, with separate directories for the dispatcher, game files, HTTP, manual sources, Nexus, the verification cache and the Wabbajack CDN, and there is a separate networking layer per service, for Bethesda, Discord, GitHub, HTTP, the Nexus API, Steam and the Wabbajack client API. The compression layer is split by format, with BSA and Zip as separate assemblies, and the hashing layer has perceptual hashing and xxHash64 in their own directories.

Funding, Signing and the Shape of the Project

The social links section says more about the project than the feature list does, because it names what the money pays for.

The Patreon page contains update posts and keeps the Code Signing Certificate, a DigiCert certificate, as well as the supplementary build server alive. A code signing certificate is what lets a Windows installer run without a scary warning, and the fact that it is renewed through donations tells you the cost model of a desktop application distributed without charging for it.

The other links are the usual ones for a project of this age. The website carries a Gallery, a Status Dashboard and an Archive Search for official Modlists, the wiki is the documentation, and the Discord is where the instructions and the support live. The README also thanks the testers and the Discord members who encourage development and help test the builds, which is an accurate description of how a project like this gets verified.

The licence section states the position in the same plain language. All original code in Wabbajack is given freely via the GPL3 license, parts of Wabbajack use libraries that carry their own Open Sources licenses and those parts retain their original copyrights, and selling of Modlist files is strictly forbidden, as is hosting the files behind any sort of paywall. The closing line is the summary of the whole project: you received this tool free of charge, respect this by giving freely as you were given.

Editorial conclusion

Wabbajack fits a modder who wants to reproduce a known configuration on a new machine, and a modlist author who wants their work distributed by reference rather than by redistribution, since the tooling and the protocol are both open. It is a poor fit for a modlist that requires a paid download, because the licence forbids it outright and the project says it will implement software that blocks the installation of paywalled lists. Before adopting it, read the modlist compilation documentation and check the supported games and mod managers page for your title, and note that the project depends on a code signing certificate kept alive by donations, which is a dependency worth understanding if you plan to run it at scale. The source is GPL3, the newest release is 4.3.0.0 from 2026-10-15, and the last push was on 2026-10-15.

Frequently asked questions

Official sources

1. Issues
2. Project website
3. README
4. Releases
5. wabbajack-tools/wabbajack on GitHub