Some mod I have installed caused a crash after idling for a while:

Oh noo. I'll think I have an idea of whats going on. I'll fix it in a few hours. Thanks for the report. :)

Can you show what mods you have installed?

Fairly certain I found the cause of this and fixed it.

I get the same. On the scene after raine's 0.15 speedrun with the circuit belts behind the turrets shooting medium biters.
My mods are just minor mods that add things and don't really alter anything in a way that should crash or remove anything expected from vanilla. Maybe except for red and green wire (a mod removes them as recipes and makes them into a tool instead that wires for free)
Mods:

base
alien-biomes
AlmostInvisibleElectricWires
AutoDeconstruct
automatic-underground-pipe-connectors
Auto_Deploy_Destroyers
BeltRouter
BigLightElectricMiningDrill
BigLightTrainStop
Blueprinter
breakable-landfill
bullet-trails
CapsuleAmmo
ChangeMapSettings
ChunkyChunks
ClearSkiesOfPeace
ctg
Dirt_Path
DoRobotsBuildAutomaticTrains
DynamicConstructionQueue
electricboiler
Enhanced_Map_Colors
EquipmentGridLogisticModule
event-listener
flib
GhostBuster
GunEquipment
HallOfFame
HandyHands
IceOre
Infinizoom
inventory-repair
ixuBottleneck
Kux-BlueprintEditor
Kux-BlueprintExtensions
Kux-CoreLib
Kux-GhostInHand
lamp-placer
LandmineGridlock
LD_AutoCircuit
leighzerlib
leighzermorphite
LoaderRedux
LootChestPlus
LootMilitaryScience
mapshot
MaxRateCalculator
miniloader
MiscLib
more-minimap-autohide-017
NextGenEvolution
Nightfall
Noxys_Extra_Settings_Info
Noxys_Trees
No_Power_Icons
NPBees2
PickerAtheneum
PickerDollies
player_request_crafting_layout
power-grid-comb
Pro-Flashlight
pushbutton
Quick-Charge-Personal-Bots-Continued-Plus
RealisticFlashlight
RoboTank
robotarmy
SignalSigns
some-autoresearch
some-corpsemarker
SpidertronEnhancements
SpidertronPatrols
stdlib
VehicleSnap
Waterfill_v17
WellPlanner
WireShortcuts

My apologies, I never clicked the submit button on the new version before I left for the day. It should be fixed now.

Thanks!