[0_1563630859187_sha256.zip](Uploading 0%) Sounds like a cool project! Java code cannot be used directly in NetsBlox but JavaScript can (using the "Javascript function" block under the "Operators" tab). This could be used to either implement sha-256 in JS yourself or to load a JS library providing this functionality. I have attached an example which uses the implementation provided at https://geraintluff.github.io/sha256/ to provide a custom block for computing the SHA-256 hash. sha256.xml