Nouns ending in -ot are usually masculine.
Is boulot masculine or feminine?
leboulot
The rule behind it
98.6% of -ot nouns are masculine
In context
Tom a chargé Mary de faire le boulot.
Tom assigned Mary to do the job.
Il m'est impossible de faire ce boulot.
That job is impossible for me to do.
Deux médecins étaient en train de parler boulot.
Two doctors were talking shop.