Compositions and methods for the treatment of toxoplasmosis, caused by the infectious eukaryotic parasite Toxoplasma gondii (T. gondii) and for the treatment of cryptosporidiosis, caused by the infectious eukaryotic parasites Cryptosporidium parvum (C. parvum) and Cryptosporidium hominus (C. hominus) are described. In particular, the present disclosure is directed to compositions and methods for inhibiting either T. gondii calcium dependent protein kinases (TgCDPKs) or C. parvum and C. hominus calcium dependent protein kinases (CpCDPKs) using pyrazolopyrimidine and/or imidazo[1,5-a]pyrazine inhibitors, of the formula, wherein the variables X, Y, Z, L, R1, and R3 are defined herein.