Various aspects include a turbomachine bucket, corresponding shim and related turbine rotor. In some cases, a steam turbine bucket includes: a blade having a first end, and a second end opposite the first end; a tip at the first end of the blade; and a base at the second end, the base including a dovetail for complementing a corresponding dovetail slot in a steam turbine rotor, the dovetail having: a body; a plurality of projections extending from the body in opposing directions for complementing a plurality of recesses in the corresponding dovetail slot; and a shim locking slot extending through the body along the opposing directions, the shim locking slot being open at a bottom surface of the body and sized to engage a shim.