The classical eight-limbed path of yoga is usually taught as its own separate system. It is also, rung for rung, already inside this song — restraint, observance, seat, breath, withdrawal, holding, meditation, and the final absorption, each one named in its own words. Climb it here, one rung at a time.
Restraining the movements of the mind — that is the whole of yoga, in half a line. The eight limbs are simply how that half-line is walked.