Factorio mod versions, and the one field that tells you the truth

Factorio solved a problem that most modded games have not, and it is worth explaining because it makes everything downstream easier.

The field that does the work

Every Factorio mod ships an info file, and that file declares which game version it targets. Not in a description, not in a forum post: a field, read by the game.

The game checks it before enabling anything. Target a version you are not running and it says so and refuses, cleanly, before anything can go wrong.

Compare that with the usual arrangement, where a mod page says "works on the latest version" in prose, that sentence was written eight months ago, and finding out means launching.

It is also why this site can state Factorio compatibility as fact rather than as a claim. The number comes from the same field the game reads.

What the 2.0 update actually did

The 2.0 release changed enough internally that most mods needed genuine work rather than a version bump. Anything that touched the systems it reorganised had to be rewritten against the new shape.

Which is why a mod that has not been updated since is not going to start working. It is not waiting for a number to be changed, it is waiting for somebody to do the work.

Saves remember their mods

A Factorio save records the exact mod set it was built with, including versions.

Load it with a mod missing and the game will tell you what is absent rather than opening something half broken. Load it with an older version of a mod than it was saved with and it will usually refuse for the same reason.

This is a feature that feels like an obstacle right up until the first time it stops you destroying a two hundred hour factory.

The practical consequence is to change mods deliberately rather than casually, and to keep a copy of a save before a large change. Factorio autosaves, but autosaves are also written with whatever mod set is loaded now.

Using the portal

The official portal has essentially everything, and the in game browser reads it directly, which makes installing genuinely simple.

What the browser is less good at is telling you what a mod depends on before you commit, and Factorio mods lean on shared libraries just as heavily as any other ecosystem. That is what the dependency list on a project page here is for.