Nilotinib and Imatinib Mesylate After Donor Stem Cell Transplant in Treating Patients With ALL or CML

Inclusion Criteria: * Body surface area \>= 1 m\^2 * Allogeneic HCT * Acute lymphocytic leukemia (ALL) or chronic myelogenous leukemia (CML) characterized by the p190 and/or p210 BCR/ABL gene rearrangement * CML in accelerated phase, blast crisis, or blast crisis remission as defined by World Health Organization (WHO) criteria * CML in chronic phase if patient age =\< 17 years or a patient of any age with CML in second chronic phase or beyond * Patients with minimal residual disease (MRD) that is not declining in response to tyrosine kinase inhibitor therapy must be screened for the T315I and other mutations * An appropriately matched related or unrelated donor * Signed informed consent * Patient must have a life expectancy of at least 2 months * Stated willingness of the patient to comply with study procedures and reporting requirements * Creatinine =\< 2.0 x upper limit normal (ULN) * Platelets \> 20 x 10\^9 /L * Serum aspartate aminotransferase (AST)/alanine aminotransferase (ALT) =\< 3 x ULN, conjugated bilirubin \< 3 x ULN * Serum potassium phosphorus, magnesium, and calcium \>= lower limit normal (LLN) or correctable with supplements prior to first dose of study drug; calcium levels may be corrected for hypoalbuminemia * Serum amylase and lipase \< 1.5 x ULN * Female patients of childbearing potential must have negative pregnancy test within 7 days before initiation of study drug dosing; postmenopausal women must be amenorrheic for at least 12 months to be considered o…