Variables casts as string instead of numbers

Hey,

I have a simple db table with some tinyints and integers. In a vue component I do some checks and calculations on the integers.

On my machine (chrome on osx) everything works fine. If I deploy the code on the server the integers are casted as strings, so my checks and additions won't work anymore.

Examples:

DB: 
job.amount = 100
job.is_printed = 0

On the server

Vue:
return job.is_printed; // return true. In the chrome vue devtool it says job.is_printed = "0"

On the osx machine:

Vue:
return job.is_printed; // return false. In the chrome vue devtool it says job.is_printed = 0

Same on calculations

On the server

Vue:
return _.sumBy(jobs, 'amount'); // 100200300

It simply connects the strings.

On the osx machine:

Vue:
return _.sumBy(jobs, 'amount'); // 600

When I explicit use the laravel casting in the model, it works on both machines.

But I want to know, why this is different on the machines?

Bye