The invention relates, in part, to a library of chimeric proteins, each chimeric protein including a mini-protein between about eight and about forty amino acids long, wherein the mini-protein has a single disulfide bond formed by a pair of invariant cysteines and has only two cysteines. The chimeric protein also includes at least a portion of an outer surface protein of a genetic package, wherein the chimeric protein is displayed on the outer surface of the genetic package. The invention also includes, in part, a mixture of nucleic acids that encode a library of the invention. The invention also includes, in part, a process for identifying proteins with a desired binding activity against a target, the process including screening a library of chimeric proteins of the invention; and identifying the chimeric protein. The invention, in part, also includes chimeric proteins expressed by a library of the invention.