Now I think I'm more confused. If I change data.raw["surface-property"]["solar-power"].default_value to 50, that doubles the power produced by all solar panels on all surfaces?

I would not expect changing the default to change the behavior of solar panels that have opted for a non-default value ...

According to https://lua-api.factorio.com/latest/prototypes/SpaceLocationPrototype.html#solar_power_in_space, the default for solar_power_in_space is 1.0. That default made me think "The value 1 means 100% of Nauvis production" but the values of solar_power_in_space (60 to 600) make it clear that ...

Reproduction
Using the default keybindings, start a new single-player game and press the keys [T], [Pause], and [Esc].

Observed behavior
The main menu opens behind the technology window.
06-23-2026, 18-28-32.png

Expected behavior
Any of (a) it's impossible to toggle the pause state when ...

Comparing the 1.1 and 2.0 documentation makes me believe that ItemProductPrototype::type is required in 2.0. However, with the mod Tricky Old Nick , --dump-data (output attached) produces at least one rocket_launch_products entry with no type. For example, at line 65882:
{
"name": "nullius-guide ...

Even when starting Factorio with a valid data cache (just written by the previous run of Factorio, with no mod or setting changes) it still refuses to use the data cache, and provides no explanation why:

0.001 2025-10-09 20:21:16; Factorio 2.0.69 (build 84148, win64, full, space-age)
0.001 ...

It appears (from data.raw["noise-function"].expression_in_range_base) that expression_in_range is a built-in function, but it isn't documented on https://lua-api.factorio.com/latest/aux ... sions.html

Will you add documentation for this function, please?

When searching for "text pl" in the mod browser, the description of Even More Text Plates has an incorrect carriage return in the middle of the word player:
08-12-2025, 09-37-55.png

If the search is adjusted so the highlight doesn't end in the middle of the word, the carriage return is correctly ...

Is there a guide for how mod and tool authors should configure Crowdin somewhere? My experience trying to configure Crowdin for translation has not been smooth, and I imagine I've reinvented a lot of wheels that have been built many times by other people:

- I had to dig around to figure out a way ...

On the other hand, Rseding already pointed out that mods have the power to specify which recipe is selected for a given item signal, so is it possible to just adjust the base mod to cause those recipes to be selected?


A mod could remove the catalyst flag
What catalyst flag? The string ...

According to https://forums.factorio.com/viewtopic.php?t=128130, item signals are supposed to sometimes not select a recipe, even when the user might expect a recipe to be selected.

As far as I can tell, there's no mention in the Lua API of what a mod needs to do in order to trigger this behavior ...

Is it possible to keep the existing logic, but add to the end of it "If no recipe was selected, and exactly one recipe outputs the item (or fluid), select that recipe"?

If there are multiple recipes (e.g. supplying the solid fuel item signal to a chemical plant) it seems perfectly reasonable to go ...

When sending the signal water-barrel to an assembler 2 in "Set recipe" mode, the assembler does not select the recipe for filling barrels, even though that recipe is unlocked.

04-11-2025, 18-16-03.png
The expected behavior is that assemblers receiving an item signal should select the single ...

When I send the flying-robot-frame signal to an assembly machine, I expect it to select the flying-robot-frame recipe. However, when the Robot repair option in Robot Attrition is set to the 75% option (instead of the default), the machine selects the logistic-robot-repair recipe instead.

04-09 ...

I loaded the attached save and hovered over the undo button, and got the attached crash. An apparently similar crash appears if I press Ctrl+Z.

The save thinks it has the mod Delete Empty Chunks enabled, because I started trying to update the mod to Factorio 2.0. You don't need that mod (the game ...

I pasted a blueprint recently and was informed "Internal server error: Weight unknown for 'one-to-one-reverse-pipe'"

Which is reasonable, but I'd like to be able to paste that blueprint anyway, and also others with modded items. Is there a way I can host/run rocketcal.cc locally and load it up with ...

When it's ready: https://mods.factorio.com/mod/bobplates ... 51e5c17b17

I see at least two problems now. First, I was excluding too many recipes, which is entirely on me.

The second is that when you said "The recipe's category, subgroup, then order," I thought you meant these values:

1: lithium-hydroxide: chemistry, ,
2: py-sodium-hydroxide: chemistry, py-rawores ...

Thank you for the additional information, but I'm still not getting the right answers in at least two cases.
Case 1
There is a vanilla item named "pistol" which is produced by a vanilla recipe named "pistol". Since the names match, that recipe is used for calculating the item weight.
The recipe ...

500° steam is unlocked by the Calcite processing (via the Acid neutralization recipe), Heating tower, and Nuclear power (both via the Heat exchanger) technologies. However, if you research Calcite processing before either of the other two, you're forced to run the steam through Steam engines ...

Bumping this: I thought I understood how weight calculation works, but when multiple recipes produce the same item (e.g. limestone in Py's mods) Factorio decides to calculate the weight based on the "extract-limestone-01" recipe instead of the "mining-limestone" recipe. I can find no obvious reason ...