An autonomous vehicle retrofit system includes: a central computer; and a braking interface to decelerate a wheel of a vehicle via actuation of a brake caliper, the braking interface further including a brake pedal; a first master cylinder assembly, mechanically coupled to the brake pedal such that actuation of the brake pedal causes actuation of the first master cylinder assembly; a second master cylinder assembly, coupled to the central computer such that the central computer controls actuation of the second master cylinder assembly; and an actuator selector, hydraulically coupled to the brake caliper, that selectively actuates the brake caliper in response to actuation of at least one of the first master cylinder assembly and the second master cylinder assembly.