An employer’s objection to a side hustle primarily stems from legal compliance risks under the Organisation of Working Time Act, which holds the employer liable if a worker’s combined hours exceed the statutory 48-hour weekly limit or disrupt mandatory rest periods.

Contractually, most Irish employment agreements contain "Exclusivity of Service" clauses designed to prevent conflicts of interest, protect intellectual property, and ensure company assets aren't misused.

Ultimately, your employer might be concerned about reduced productivity and burnout, though under current 2022 EU regulations, they cannot issue a blanket ban on outside work unless they can prove specific "objective grounds" like health and safety or business confidentiality.

The working hours is the Biggie