Essentially what the game does is something like this:
--start of tick--
1500 resources
Space dock: -200
Space dock: -200
Engineer: -400
Engineer: -400
Engineer: -400 *paused, insufficient funds*
Engineer: -400 *paused, insufficient funds*
Starship Constructor: -1000 *paused, insufficient funds*
Needler Turret: -50
Needler Turret: -50
Resource Node: +500
Needler Turret: -50
Needler Turret: -50
Engineer: -100
Engineer: -100
Engineer: -100
Engineer: -100
Engineer: -100
Engineer: -100 *paused, insufficient funds*
Engineer: -100 *paused, insufficient funds*
Engineer: -100 *paused, insufficient funds*
Engineer: -100 *paused, insufficient funds*
Resource Node: +500
Resource Node: +500
Resource Node: +500
--end tick--
1500 resources
Just as an example. Actual processing order I've heard is based on when they were built.