Error: Missing value after --simulation

You may see this error in your flood logs which indicates that we were unable to programatically determine which simulation to run in your test plan. ​

This can occur if the primary .scala file uploaded for Gatling test does not have the following pattern:

/class (\w+) extends Simulation/
e.g.
class YourSimulationName extends Simulation { ...

It can also happen if multiple .scala files are uploaded, in which case you should adopt the advanced scenario demonstrated here which uploads a zip file containing dependent .scala files.