A method of identifying a peptide binder comprising the steps of: a) exposing a protein target of interest to a peptide array produced by maskless photolithography comprising a first population of peptide binders, whereby the protein target binds to at least one peptide binder comprising the population; b) identifying overlap in peptide binder sequences comprising the population which bind the protein target of interest, whereby a core binder sequence is determined; c) performing at least one alteration selected from a single amino acid substitution, a double amino acid substitution, an amino acid deletion, and an amino acid insertion of amino acids comprising the core binder sequence, whereby a second population of core binder sequences is generated; d) exposing the second population to the protein target, whereby the protein target binds to at least one peptide sequence of the second population; e) identifying one or more sequences of the second population demonstrating strong binding properties to the protein target, whereby a matured core binder sequence is determined; f) performing at least one of N-terminal and C-terminal extension of the matured core binder sequence determined in step e, whereby a population of matured extended peptide binders is generated; g) exposing the protein target of interest to a peptide array produced by maskless photolithography comprising the population of matured peptide binders generated in step f; and h) identifying overlap in the N-terminal or C-terminal peptide binder sequences of the peptides comprising the population of mature peptide binders, whereby an extended, matured core peptide binder sequence is determined. a) exposing a protein target of interest to a peptide array produced by maskless photolithography comprising a first population of peptide binders, whereby the protein target binds to at least one peptide binder comprising the population; b) identifying overlap in peptide binder sequences comprising the population which bind the protein target of interest, whereby a core binder sequence is determined; c) performing at least one alteration selected from a single amino acid substitution, a double amino acid substitution, an amino acid deletion, and an amino acid insertion of amino acids comprising the core binder sequence, whereby a second population of core binder sequences is generated; d) exposing the second population to the protein target, whereby the protein target binds to at least one peptide sequence of the second population; e) identifying one or more sequences of the second population demonstrating strong binding properties to the protein target, whereby a matured core binder sequence is determined; f) performing at least one of N-terminal and C-terminal extension of the matured core binder sequence determined in step e, whereby a population of matured extended peptide binders is generated; g) exposing the protein target of interest to a peptide array produced by maskless photolithography comprising the population of matured peptide binders generated in step f; and h) identifying overlap in the N-terminal or C-terminal peptide binder sequences of the peptides comprising the population of mature peptide binders, whereby an extended, matured core peptide binder sequence is determined. <EOS>