My current Fortune 500 tech company's contract explicitly said that if I moonlight, I cannot work for their competitors. And if I get a second job or contract work, I should discuss it with my manager or HR. It does't say anywhere that I cannot have second job at all.

I know 2 SWE in the company who actually discussed this with their managers and got okay in writing for their consulting businesses.

EDIT: Really curious if SWE actually read their contracts or they just assume that they are not allowed. I don't remember my contracts from earlier jobs. It would be interesting if we can have a site like levels.fyi for contracts.

I moonlighted for a while, and I checked my primary job's employment agreement first. All it said is that I can't be simultaneously engaged by competitors. No requirement to inform my manager or the company. Lots of people in my company have side businesses (some rebuild and sell laboratory instrumentation, others contract, etc).

I was surprised when I discovered the permissive nature of my company, but I've never seen it be a problem for anybody.

There's probably something in the business rules about conflict of interest and how strictly that's defined/interpreted with respect to side gigs will probably depend on the employer. I doubt many explicitly say you can't have a second full-time job similar to what you do here because, well, that's obvious isn't it?

At the same time, so long as you get your work done, most companies aren't going to object to your (mostly) nights and weekends hobby business or getting a degree (assuming you've worked out the details with your management).

That's how mine is as well.

Ditto - mines the same. Basically, no working for competitors.

Does that stipulation that they write into the contract have teeth though? A lot of companies put a lot of stuff into contracts, it doesn't make it enforcable.

The contract may not have teeth, the employer doesn’t own 24 hours of an employee’s time and has no legal basis to dictate what an employee does outside of the workplace.

However, in the US “at-will” employment is the norm, which means either party can terminate the employment at any time for any reason, or no reason. If the employer finds out an employee is moonlighting or freelancing in their spare time they can simply fire the person, and cite violation of policy or give almost any reason that isn’t illegal. The contract would only matter if the case got into court, and that’s unlikely to happen since the employee has no right to a job in the first place.